determination of retinal thermal hazard and blue light photochemical hazard protection
TRANSCRIPT
Determination of Retinal Thermal Hazard and Blue Light Photochemical Hazard Protection Needed by Automatic Welding Filters
Bestämning av Skyddsbehov för Automatiska Svetsglas Gällande Riskerna för Termisk och Fotokemisk Skada på Näthinnan
AKOTO CHAMA LEONEL
Degree Project Mech. Engineering 2009 Nr: E 3726 M
Determination of Retinal Thermal Hazard and Blue Light Photochemical Hazard Protection Needed by
Automatic Welding Filters
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Akoto Chama Leonel
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EXAMENSARBETE
D-Nivå Maskinteknik
Program Reg nr Omfattning
Maskinteknik – produkt- och produktionsutvecklling,
30 ECTS E 3726 M 30hp
Namn Datum
Akoto Chama Leonel 2009-09-20
Handledare Examinator
Roger Johansson
Företag/Institution Kontaktperson vid företaget/institutionen
3M Svenska AB / Research and Development Department Kristna Magnusson
Titel
Bestämning av skyddsbehov för automatiska svetsglas gällande riskerna för termisk och
fotokemisk skada på näthinnan.
Nyckelord
Termisk, blått ljus, fotokemisk, risker, skydd, automatisk, svets, filter
Sammanfattning
Nya resultat inom den biologiska forskningen har visat att de tidigare gränserna för högsta
tillåtna exponering (MPE) av artificiell optisk strålning för skydd av arbetare, var strängare än
nödvändigt. Utgående från färska gränsvärden för artificiell optisk strålning har det här arbetet
fokuserat på att undersöka vilken nivå av dämpning av det synliga ljuset som är nödvändig när
ett automatiskt svetsglas fallerar att slå om vid svets. Resultat från jämförelse mellan olika
standarder för maximal exponering användes som utgångspunkt för att undersöka behovet av
krav på Vis/IR- och blåljustransmittans för automatiska svetsglas. Verkliga och antagna
spektralfördelningar användes för att simulera olika fall av artificiell optisk strålning. Ett
excel-diagram för att beräkna exponeringsvärden från olika ljuskällor samt att beräkna viktade
transmittanser utgående från spektrala transmittansmätningar på svetsfilter togs fram under
projektets gång. Excel-diagramet utvecklades och testades utgående från kända
produktegenskaper för att verifiera tillförlitligheten. Slutsatsen från det här projektet är att det
behövs dämpning av det synliga ljuset i ljusa läget om täthetsgraden i det mörkaste läget är 11
eller högre. Det visades också att ett befintligt automatiskt svetsglas med stor marginal ger
tillräckligt skydd även om produkten fallerar att slå om vid svets.
Determination of Retinal Thermal Hazard and Blue Light Photochemical Hazard Protection Needed by
Automatic Welding Filters
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DEGREE PROJECT
Magister Thesis Mechanical Engineering
Degree Program Reg number Extent
M.Sc. Mechanical Engineering - Product and Production
Development, 30 ECTS
E 3726 M 30 ECTS
Name of student Year-Month-Day
Akoto Chama Leonel 2009-09-20
Supervisor Examiner
Roger Johansson Company/Department Supervisor at the Company/Department
3M Svenska AB / Research and Development Department Kristina Magnusson
Title
Determination of Retinal Thermal Hazard and Blue Light Photochemical Hazard Protection
Needed by Automatic Welding Filters
Keywords
Thermal, Blue Light, Photochemical, Hazard, Protection, Automatic, Welding, Filters
Summary
Recent developments in biological research, has shown that the initial maximum permissible
exposure (MPE) limits for protection of workers from risks associated with artificial optical
radiations were more stringent than needed. Using the most recent MPE limits for artificial
optical radiation this piece of work was focused on the investigation of the level of visible
light attenuation needed by automatic welding filters in case of switching failure. Results from
the comparison of different exposure standards were employed in investigating the need of
Vis/IR and blue light transmittance requirement for automatic welding filters. Real and
arbitrary spectra were taken into consideration for the worst and best case scenarios of
artificial optical radiations. An excel worksheet developed during the execution of this project
took into consideration the exposure from different light sources and the precision of the
spectrometer used in measuring the transmittances of a welding filter. The worksheet was
developed and tested with known product properties to investigate the validity of its
formulation. The conclusion drawn from this project was that attenuation in the light state will
be needed for products with the darkest state shade 11 or higher. Also shown is that current
welding filter protects the eye well enough even in the case of switching failure.
Determination of Retinal Thermal Hazard and Blue Light Photochemical Hazard Protection Needed by
Automatic Welding Filters
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Abstract Recent developments in biological research, has shown that the initial maximum permissible
exposure (MPE) limits for protection of workers from risks associated with artificial optical
radiations were more stringent than needed. Using the most recent MPE limits for artificial
optical radiation this piece of work has focused on the investigation of the level of visible light
attenuation needed by automatic welding filters in case of switching failure. Results from the
comparison of different exposure standards were employed in investigating the need of Vis/IR
and blue light transmittance requirement for automatic welding filters. Real and arbitrary
spectra were taken into consideration for the worst and best case scenarios of artificial optical
radiations. An excel worksheet developed during the execution of this project took into
consideration the exposure from different light sources and the precision of the spectrometer
used in measuring the transmittances of a welding filter. The worksheet was developed and
tested with known product properties to investigate the validity of its formulation. The
conclusion drawn from this project was that attenuation in the light state will be needed for
products with the darkest state shade 11 or higher. Also shown is that current welding filter
protects the eye well enough even in the case of switching failure.
Determination of Retinal Thermal Hazard and Blue Light Photochemical Hazard Protection Needed by
Automatic Welding Filters
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Akoto Chama Leonel
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Acknowledgements This research project would not have been possible without the support and encouragement of
many people. I wish to express my gratitude to my supervisor, Kristina Magnusson (Senior
Optics Specialist at 3M) who was abundantly helpful and offered invaluable assistance,
support and guidance. Deepest gratitude are also due to the members of the supervisory
committee (The Optic group at 3M) and to all those at the R&D Department of 3M without
whose knowledge and assistance this study would not have been successful. Not leaving out
special thanks to 3M for the financial support throughout this project.
I would also like to extend my gratitude to my teachers, Roger Johansson and Bengt Lofgren
for their support and encouragement.
Special thanks also to all my friends, for their encouragement and invaluable assistance.
I would also like to convey thanks to the University and Department for providing the
possibility of carrying out this research project to a successful completion.
I wish to express my love and gratitude to my beloved families; for their understanding &
endless love, through the duration of my studies, most especially to my mum: Diana, brothers:
Roland, Terence and Derick and to my sister Ernestine.
I am grateful also to the examples of my late father, Eki Thomas. His unflinching courage and
conviction will always inspire me, and I hope to continue, in my own small way, the noble
mission to which he gave his life. It is to him that I dedicate this work.
Determination of Retinal Thermal Hazard and Blue Light Photochemical Hazard Protection Needed by
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Table of Contents Abstract ............................................................................................................................ 2
Acknowledgements .......................................................................................................... 3
Table of Contents ............................................................................................................. 4
1 Introduction .............................................................................................................. 5
1.1 Background ........................................................................................................ 5
1.2 Problem .............................................................................................................. 5
1.3 Objective ............................................................................................................ 5
1.4 Delimitations ...................................................................................................... 5
1.5 Approach ............................................................................................................ 6
1.6 Report Outline .................................................................................................... 6
2 Method ..................................................................................................................... 7
2.1 Introducing the Liquid Crystal (LC) Technology ................................................... 7
2.2 Introducing the Optics of the Eye ..........................................................................18
2.3 Welding and the Emission of Electromagnetic Waves ..........................................25
2.4 Speedglas and the LC-Technology ........................................................................28
3 Execution .................................................................................................................38
3.1 Comparison of Different Standards .......................................................................38
3.2 Study of Filter Characteristics...............................................................................57
4 Result : Determination of Damage from Intense Light Exposure ..............................69
5 Discussion ...............................................................................................................84
6 Conclusion / Recommendations ...............................................................................85
7 References ...............................................................................................................87
Appendices ......................................................................................................................88
Appendix A (Annex) Calculations ...............................................................................88
Appendix A Data Sheet .......................................................................................... 118
Determination of Retinal Thermal Hazard and Blue Light Photochemical Hazard Protection Needed by
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1 Introduction
1.1 Background
Recent developments in biological research, has shown that the initial maximum permissible
exposure (MPE) limits for protection of workers from risks associated with artificial optical
radiations were more stringent than they really should have been. These restrictions which
were stipulated in the 1999 Technical Report of the International Electrotechnical
Commission (IEC) were more restrictive than the most recent investigated permissible
exposure limits of the eyes. As a result of this and because the products where standardized
according to initial research reports, it is therefore imperative that the products be investigated
to see if they do not pose any threat to humans even within the limits of recent MPEs.
1.2 Problem
The problem here was to determine whether or not there is any risk involved in using
automatic welding filters for protection against artificial optical radiations according to the
new exposure standards, within 0,5 s of switching failure. If there is, to what extent should
protection be needed?
(Note: Since the blink reflex is often mentioned as 0.25 s, choosing 0.5 s for switching failure
gives some error margin.)
1.3 Objective
The objective of this project is to determine the thermal and blue light photochemical hazard
protection needed by automatic welding filters in case of switching failure. The required
protection in the light state, when welding filter fails to go to the intended darkest state is
searched.
1.4 Delimitations
In this project investigations were made within the Electromagnetic spectral range from
300nm to 1400nm leaving out all other wavelengths of the EM spectrum. This project
stipulated the expected design properties but did not go into the actual fabrication of the
system. Design properties were mainly focused on the blue light and Infrared regions of the
EM spectrum.
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1.5 Approach
In order to determine the thermal and blue light photochemical hazard protection needed by
automatic welding filters in case of switching failure ( i.e. the required protection in the light
state, when a welding filter fails to go to the intended darkest state) and because these filters
use the liquid crystal technology for its operation, the work was carried out as follows:
First of all, a lot of background studies was done in order to understand the following:
- Liquid Crystal Technology
- Optics of the eyes
- Welding and the emission of electromagnetic spectra
- Differences between various standards
After a clear understanding of the problem, an excel worksheet was developed (see
accompanying CD) and used to:
- Understand the behaviour of the filter
- Simulate spectral data
At the end of the analysis logical conclusions were drawn from the results obtained.
1.6 Report Outline
The product under investigation uses mainly the Liquid crystal (LC) technology in its
operation. As a result of this, the report started with a general introduction of the LC-
Technology to introduce the main concepts considered during the investigation. This was
closely followed by an introduction of the optics of the eye(organ of the body directly
affected), welding and the emission of electromagnetic spectra (processes that produce
radiations for which protection is needed) with both limited to areas related to the objective of
the project. After these, a closer look was made on the specific application of the LC-
Technology on the speedglas (product under investigation) and the operations and principles
of its constituent parts. With a good knowledge and understanding from the background, the
next step introduced the preliminary investigation to proffer a solution to our problem, here
different standards were then compared in order to choose a final standard to analyse the
protection needed. With a standard now adopted, it was then employed in the study of the
filter characteristics. With a deep understanding of the product properties and its operation
principles, the damage level from intense light exposure was determined through simulation
on an excel worksheet, followed by a conclusion stating clearly to what extent this project
attained its original objective..
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2 Method The methods used here were both experimental and analytic, but first we start by introducing
the necessary literature to understand the technology behind the product, the source of EM
radiations and how they may affect the eyes.
2.1 Introducing the Liquid Crystal (LC) Technology
2.1.1 Electro Optic Filters
Electro optic filters could be described as electromagnetic wave filters that use the interaction
between liquid crystal molecules and an external electromagnetic field for filtration.
Before the introduction of electro-optic filters, the optics of liquid crystals shall be briefly
introduced since it constitutes the main filtration element.
The main reason for the significant optical effects of liquid crystals is the large optical
anisotropy of these materials (with ∆n typically in the range 0.1 to 0.3) and also because the
optic axis can easily be reoriented by external forces such as electric or magnetic fields or
surface interactions. As the case may be, in the presence of an external field, the molecules
turn to align themselves in the direction of the field with the completeness of the alignment
proportional to the field strength.
The anisotropic nature of liquid crystal molecules and the macroscopic ordering makes the
material birefringent and hence the optical properties depend on the polarization direction of
the propagating light. [1]
In the presence of an electric field, the structure and thermodynamic properties of a dielectric
anisotropic medium changes. These changes include a shift in the phase transition points,
change in order parameters, induced new symmetry, a reorientation of the director bringing
about strong changes in the optical properties of the liquid crystals such as the transmittance,
reflectance, refraction etc.[2]
Electro-optic filters make use of the above mentioned properties of liquid crystals to filter
electromagnetic waves passing through them.
In general there are many different applications of electro-optic filters but for the purpose of
this thesis studies will be limited only to Automatic Darkening Welding filters.
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Automatic Darkening Filters are filters which utilise Liquid Crystal Technology (LC-
Technology) to filter electromagnetic waves. Other applications of electro-optics include:
electro-optic shutter, electro-optic light modulation and acousto-optic beam deflection.
2.1.2 Twisted Nematic Liquid Crystal Cells
In the absence of an external voltage across a liquid crystal sample the molecules turn to bend
around their axis given rise to a twist angle (θ). Depending on the angle we can identify 4
different types of twists:
θ = 90o the standard 90o twisted nematic cell is form
θ < 90o gives rise to the low-twist (L.T.) cell
90< θ ≤ 180 we have high twist cells
θ > 180o we have the super twist cells.
For the purpose of this project we shall be limited only to the standard twisted nematic with a
twist angle of 90o.
Based on the director distribution, it is possible to derive the electro-optical response of
nematic liquid crystal cells (such as birefringence), rotation of polarization plane of incident
light, total internal reflection, or some other important characteristics of the cell [3]. In order
to understand the optical characteristics of a liquid crystal layer in the electrically controlled
birefringence (ECB) effect, let us consider Figure 2.1, with the initial homogenous director
oriented along the x-axis (θ = 00, no twist).
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Fig 2.1[3] Homogenous (S-effect)
If the applied voltage is below the threshold, the nematic liquid crystal layers manifest a
birefringence of
∆n = ne – no = n - n (1)
When the field exceeds its threshold value, the director deviates from its orientation along the
x-axis while remaining perpendicular to the y-axis. Therefore the refractive index of the
ordinary ray remains unchanged no = n, while at the same time, the refractive index of the
extraordinary ray (ne) decreases, tending towards no.
The relationship between the magnitude of ne and the angle of orientation of the director θ (z)
is shown below:
ne(z)= neno/√ (ne2sin2θ(z) + no
2cos2 θ (z)) (2)
Also the intensity of the light passing through the cell depends on the angle(φo) between the
polarization vector of the incident beam and the initial orientation of the director of the
nematic liquid crystal. This relationship is shown in the following formula:
I = Iosin2φosin2(∆Ф/2) (3)
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Where Io = Intensity of plane polarised light incident on cell
∆Ф = Change in phase difference
The effects of phase modulation for an initial planar orientation of the director (along x) with
positive dielectric or diamagnetic anisotropy (∆є, ∆X >0) and with the field applied along the
z-axis (see figure 1.1 above) is called the S-effect because , though a bend deformation is
introduced above the threshold, the initial deformation is a splay deformation.
The applied field causes a phase difference to arise between the ordinary and the
extraordinary rays and the intensity of the light oscillates according to eqn. (3) above.
In the case when the bend deformation is in the initial stages of its development (Fig 2.2) the
corresponding electro optic effect is called the B-effect, and takes place for negative values of
the dielectric anisotropy ∆є <0
Fig 2.2 [3]Homeotropic (B-effect)
However the final orientation of the director is not defined (degenerate), and the sample does
not remain monodomain and contains specific defects (umbifics) [3]. In principle, the
preferred direction of the final orientation of the director can be established and these defects
in the structure eliminated by special preparation of the surfaces with a slight pre-tilt.
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There is also another twist effect caused by a pure twist deformation shown in fig 2.3 below.
The electro-optical or magneto-optical effect corresponding to this geometry is called the T-
effect and is most amendable for theoretical analysis and less suitable for experimental
investigations since the filed induces biaxiality in the nematic liquid crystal.
Fig 2.3 [3]Homogenous (T-effect)
Since the Optic filter in this project operates within the conditions of the S-effect (∆є, ∆X >0)
we shall limit our discussion within this region.
The above discussion about ECB effects leads us to a fundamental problem of switching time.
2.1.3 Switching Time
In order to address this problem we need to specify conditions under which we can have
full switiching from Imax to Imin with minimal response time.
According to (3) such a switching is stipulated when the phase difference ∆Ф is changed as
much as π. When a voltage U is applied across a nematic cell corresponding to a maximum
intensity Imax , then to attain another state with Imin we have to supply an additional voltage Uл
≥ ∆U, where ∆U is the minimum possible value of Uл (see figure 2.4 below)
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Fig 2.4[3] Electrically controlled birefringence in homogenous liquid crystal cell (S-effect).
Polarizer (P) is crossed with the analyzer (A) and set at the angle φo with respect to the initial
liquid crysral director. Below the intensity / of the transmitted light and phase, difference –δ are shown versus the applied voltage. The phase π switching regime is indicated, which result
in the variation of the intensity from Imax to Imin.
Times ζл which correspond to the total intensity variation Imax ↔ Imin decreases with increasing
applied (bias) voltage U, and pass through a minimum at the intermediate voltages U≈1,3US,
where US is the S-effect threshold voltage (see fig. 2.4 above). For large amplitudes of a
switching pulse Uл >> ∆U, the reaction times for a phase lag change by л : ζr(л) can reach the
values of 20 microseconds at room temperature.
As a result of the low-frequency relaxation of є, the three to four orders of magnitude
larger off-times can be decreased to the value of ζr(л), as the dielectric anisotropy of the liquid
crystal becomes negative at a certain frequency. Hence it is possible to address the cell with a
high frequency signal and to force the director to rotate rapidly into the homogenous “off”
configuration. The minimal times of the total switching cycle, Imax → Imin → Imax , obtained in
the S-effect with the double frequency addressing technique, attained 40-50 microseconds at
room temperature. A further decrease of response times is very difficult due to the appearance
of defects in thin nematic cells at high voltages, which hinder fast electro-optic switching in
the S-effect[3].
The main disadvantage of the S-effect for display applications is the strong dependence of
the transmitted intensity on the light wavelength and the non-uniform transmission-voltage
characteristics at oblique light incidence. However, it is possible to avoid them by placing a
compensating birefrigent plate between the liquid crystal cell and one of the polarisers or by
using two nematic S-cells in series that have perpendicular initial directors.
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Special attention should be paid to the so called л cells, when the birefringent intensity is
switched in the last fall of the oscillation curve (see fig. below). In this case, the switching is
attained due to very slight variation of the director distribution within the narrow regions near
the boundaries, thus resulting in a very fast response speed. The corresponding switching
times can be estimated according to the formula [3]:
ζ≈ (∆/л/2л)21/(1 - βUл/Uo)2γ1λ2/K11∆n2 (4)
Where (∆/л)≈1 is a relative phase difference for the last intensity fall and β≈1 is the liquid
crystal material constant. As we may see the response time does not depend on the cell
thickness. Combining л cells with phase retardation plates, both with positive and phase shifts,
it is possible to optimize a contrast and colour uniformity of the liquid crystal cell. The
contrast ratios of 50:1 and more can be obtained for viewing angles of about 20o from normal
to the cell.
We also have some characteristics induced by the B-effect, but will not be discussed in this
project.
2.1.4 Twist Effect
If the directions x and y of the planar orientation of the nematic liquid crystal molecules on
opposite electrodes are perpendicular to each other and the material has a positive dielectric
anisotropy ∆є>0, then when an electric field is applied along the z-axis (see figure 2.5) a
reorientation effect occurs, which is a combination of the S, B, and T deformations.
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Fig 2.5 [3] Diagramatic representation of the twist effect
In the absence of the field, the light polarization vector follows the director and, consequently,
the structure rotates the polarization plane up to the angle characterizing the structure φm = л/2
(see fig 2.5). This specific waveguide regime (the Mauguin regime) takes place when[3]
∆nd / λ >> 1 (5)
When the applied voltage exceeds a certain threshold value
Utw= л[л(4K11 + K33 – 2K22)/∆є]1/2 (6)
The director L deviates from the initial orientation so that the linear dependence of the
azimuthally angle φ (z) disappears and the tilt angle θ (z) becomes nonzero (see fig 2.7). The
qualitative character of functions φ (z) and θ (z) for different voltages is shown in figure 2.6.
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Fig 2.6[3] Distribution of the Director angles θ (z) and φ (z) in the twist effect for different
voltages U : (a) U ≦ Utw ; (b) Utw < U1 < U2 < U3.
Since the director tends to orient perpendicular to the substrate, the effective values of ∆n
decreases and, for a certain voltage (optical threshold of the twist Uopt), the waveguide regime
no longer remains. Let us note that, despite the fact that the director starts to reorient at U =
Utw, a visible change of the twist cell transmission is observed only for U = Uopt > Utw (see fig
2,8)
Figure 2.7 gives the dependence of the optical transmission of a twist cell for both the
conventional geometry PL(0) and when the polarizer P forms an angle 45o with respect to
the orientation of the director at Z = 0.
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Fig 2.7[3] Optical response of the twist-cell between parallel polarizers: curve 1: polarizers
are parallel to the director on the input surface of the cell (conventional orientation); curve 2:
polarizers at the angle of 45o to the director on the input surface (maximum birefringence
intensity); curve 3: phase retardation calculated from curve 2
The deformation threshold, Utw = 6V, determined by extrapolating the linear section phase
delay curve to ∂(U) = 0, coincides with that calculated from (6). The optical threshold for twist
effect increases with decreasing wavelength (Uopt = 8,9V and 10,2V for λ=750 and 450nm
respectively), since the cut-off implied by the Mauguin condition (eqn. 7) occurs at a higher
voltage for shorter wavelengths (eqn 5)
∆nd / λ = (4m2 – 1)1/2 / 2, m = 1, 2, 3, … (7)
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2.1.5 Dynamics of Twist Effect
The response of a twist cell to an external voltage pulse has been studied by a number of
workers:[2]. A typical oscillogram of the switching effect under conditions in which the
external voltage does not greatly exceed the threshold value (2,5 times greater) is shown in Fig
2.8 (curve 2).
Fig 2.8[3] Oscillogram for switching on (A, resolution of 100 ms per division) and
oscillogram for switching off (B, resolution of 1 s per division) for twist effect ( the cell is the
same as in Fig. 2.7). (1) Voltage pulse, f = 1 KHz, U = 25 V ; (2) twist effect, output for the
ray polarized parallel to the director when z = 0; and (3) output for a cell rotated through 450
around the direction of the beam
Another curve (curve 3) is superimposed on the same oscillogram showing the response of
the same twist cell rotated through an angle of 45o ( about the normal) to the light polarization
vector, so that the phase lag for the exit ray with elliptical polarization can be recorded. By
comparing the oscillograms it can easily be seen that the rise and decay times of the optical
response in the twist effect are significantly less than the corresponding times for deformation
of the layer.
However, qualitatively, the times for both the twist effect and the layer deformations are
proportional to the viscosity and to the square of the thickness, and inversely proportional to
an elastic constant. Also the rise times are inversely proportional to the difference (U2 – Utw2)
[2]..
For higher applied voltages, the edge of the twist effect oscillograms develops a
characteristic bounce. This effect is accounted for theoretically by allowing for the backflow.
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The point is that, in the initial stages of relaxation, the maximum elastic torque is found in the
region of rapid change in θm with the z-coordinate in the vicinity of the walls as in the ECB
effect.
The greatest rate of reorientation of the director also occurs in this region, inducing the
maximum associated flow of the liquid. This flow influences the director in the layer centre in
such a way that the angle θm increases (to values above π/2). As relaxation proceeds, the
backflow decreases and the director can return to its initial state (θm ~ π/2) under the elastic
forces. This corresponds to the maximum transmission of the cell (a bounce of the rear edge).
Relaxation then continues until θm = 0.
There is also the possibility of decreasing the twist-effect relaxation times by applying a field
with a frequency greater than that at which the dielectric anisotropy changes sign. The best
earlier result in this dual-frequency addressing scheme [2] were achieved by Rayans and
Shank (a 100% modulation of the light with a frequency of 25Hz). This frequency can be
increased by a factor of 20. However, higher operating voltages and a limited operating
temperature range prevent the dual frequency addressing scheme from finding commercial
application.
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2.2. Introducing the Optics of the Eyes
Since this project concerns hazards caused to the eyes from exposure to harmful radiations, it
is very important to understand those aspects of the eyes that are directly concerned.
2.2.1 Human Factors
Human factors or ergonomics is concerned with the way a product is made for a productive
and healthy interaction between a human being and a machine. Human factor engineers
approach the problem of human interface to a machine by assuming that the human is an
instrument whose complex design is complete and unalterable- a design to which a product
must link in order to get optimum exchange of information [4]. As applied to LCDs and other
information displays, emphasis will be placed upon three areas within the broader discipline of
human factors.
a) Anthropometry
For optimization of product properties, the physical configuration of systems needs to
match the physical capabilities of the users. Anthropometric scientific data is available in the
form of detailed tables and charts indicating the range of human body dimensions from small
female (5th percentile) to large (95th percentile), that can be applied to the products for
optimization.
b) Sensory
Sensory human factors determine the characteristics of the products that output or input
information to the human system with emphasis on visual, auditory and colour applications,
voice I/O, touch panels etc. Available information on sensory capacity is much less complete
than for anthropometry.
c) Cognitive
Cognitive human factors involve the use of human mental capability and capacity to design
systems. Some examples include menu configuration and lay out, error handling and
messaging. The cognitive area has the weakest database. With increasing intelligence of
electronic instrumentation, the demand for more research into the cognitive area also
increases.
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2.2.2 The Electromagnetic Spectrum and the Capabilities and Limitations of the Human
Visual System
We perceive objects by light coming from them and their surroundings into our eyes. Light
is that part of the electromagnetic spectrum (see fig 2.9 on page 19) which has the ability to
produce response in photoreceptors of the human eye and hence visual sensation. Different
individuals have different levels of sensitivity to the electromagnetic spectrum, as a result of
which, there are no precise boundaries denoting the wavelength range of light. For scientific
analysis, this range is commonly taken as 380-780 nm. Under certain conditions some
observers can see an even broader range (i.e. 360nm-830nm) of the electromagnetic spectrum.
However the extremely precise boundary is not very critical as the human eyes has maximum
sensitivity at ~555nm and has extremely low sensitivity outside the 400nm-700nm range.
Different regions of this visual spectrum exhibit different colours (fig 2.9 on page 19).
The human visual system is an incredibly complex optical instrument in which the stimulus, a
constantly changing pattern of light, is transformed into a response, a pattern of electrical
signals that travels along the optical nerve, where they produce the perception we call
seeing[4]. The operation of the eye involves optics, photochemistry, neurobiology and
electrophysiology. Light rays from the object strike the cornea and thereby are nearly focused
on the retina. Fine focusing is achieved by the lens. As the distance between the lens and the
retina is fixed in the human eye, precise focusing is achieved through accommodation
(changing the optical power of the lens). If the light intensity is high, the iris diaphragm
contracts so that the pupil becomes small and only the centre of the lens is used. The central
part of the lens gives the sharpest image.
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Fig 2.9 Electromagnetic spectrum (courtesy of Burle Industries, Inc.)
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2.2.3 Spectral Sensitivity and Hazard Weighting Functions of the Human Eye
The human eye is characterised by different response functions depending on the particular
aspects on investigation.
For the purpose of this project discussion will be only about 3 different types of response
weightings and their significance.
a) Photopic Response Function
A luminous efficiency function represents the eye’s sensitivity to the visible spectrum as a
function of wavelength. Sometimes it is also called a relative luminous efficiency, luminosity
or sensitivity function. Luminous efficiency function forms the basis of present day
photometric measurements. The photopic (V(λ)) relative luminous efficiency function gives
the ratio of the radiant flux at wavelength λm to that at wavelength λ, when the two fluxes
produce the same photopic luminous sensation under specified viewing conditions[4]. λm is
chosen such that the maximum value of this ratio is unity. For photopic or daylight vision λm
is taken as 555nm where the eye has maximum photopic sensitivity (see fig 2.10 (a) below).
Spectral Weight Distribution Function
0
0,2
0,4
0,6
0,8
1
1,2
0 200 400 600 800 1000
λ(nm)
V(λ
)
V(λ)
Fig 2.10 (a) Photopic Relative Luminous Efficiency curve
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Spectral Weight Distribution Function
0,0001
0,001
0,01
0,1
1
0 200 400 600 800 1000
λ(nm)
V(λ
)
V(λ)
Fig 2.10 (b) Photopic Relative Luminous Efficiency curve (logarithmic scale)
This indicates that the eye is most sensitive at a small interval range for which this is the mid
point, but the sensitivity drops to zero as the wavelength moves further away from this point
on either sides as shown on the graph. Fig 2.10 (b) shows V(λ) plotted on a logarithmic scale.
b) Blue Light Hazard Response Function
This is the hazard response function that describes the hazards caused to the eye within the
wavelength range of 300nm to 700nm. The main type of hazard in this region is the
photoretinitis and affects mostly the eye retina. It is mathematically characterised by B(λ), a
dimensionless spectral weighting function taking into account the wavelength dependence of
the photochemical injury caused to the by blue light radiation[5]. This distribution is shown on
the graph below (fig 2.11 (a)) and it is used in calculating the effective blue light radiance (LB
see eqn 17 of chapter 3) expressed in watts per square metre per steridian [Wm-2sr-1].
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Spectral Weight Distribution Function
0
0,2
0,4
0,6
0,8
1
1,2
0 100 200 300 400 500 600 700 800
λ(nm)
B(λ
)
B(λ)
Fig 2.11 (a) Blue Light sensitivity curve
Spectral Weight Distribution Function
0,001
0,01
0,1
1
0 100 200 300 400 500 600 700 800
λ(nm)
B(λ
)
B(λ)
Fig 2.11 (b) Blue Light Sensitivity curve (logarithmic scale)
Observe that the peak of the hazard occurs when λ~440nm. This indicates that more injury is
sustained at a small interval range for which this is the mid point, but the hazard drops to zero
as the wavelength moves further away from this point on either side. Fig 2.11 (b) shows B(λ)
plotted on a logarithmic scale.
c) Visible and IRA Hazard Response Function
This is the hazard response function that describes the hazards caused to the eye within the
wavelength range of 380nm to 1400nm. The main type of hazard in this region is the retinal
burn and affects mostly the eye retina. It is mathematically characterised by R(λ), a
dimensionless spectral weighting function taking into account the wavelength dependence of
the thermal injury caused to the eye by visible and IRA radiation[5]. This distribution is
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shown on the graph below (fig 2.12 (a)) and it is used in calculating the effective visible and
IRA radiance (LR see eqn 23 of chapter 3) expressed in watts per square metre per steridian
[Wm-2sr-1].
Spectral Weight Distribution Function
0
2
4
6
8
10
12
0 200 400 600 800 1000 1200 1400 1600
λ(nm)
R(λ
)
R(λ)
Fig 2.12 (a) Visible and IRA sensitivity curve
Spectral Weight Distribution Function
0,01
0,1
1
10
0 200 400 600 800 1000 1200 1400 1600
λ(nm)
R(λ
)
R(λ)
Fig 2.12 (b) Visible and IRA sensitivity curve (logarithmic scale).
Observe that the peak of the hazard occurs when λ is in the approximated interval of 435nm to
440nm. This indicates that more injury is sustained at a small interval range for which this
interval is a subinterval, but the hazard drops towards zero as the wavelength moves further
away from this range on either sides. Fig 2.12 (b) shows R(λ) plotted on a logarithmic scale
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2.3 Welding and the Emission of Electromagnetic Waves
The arc welding process is usually characterised by the emission of electromagnetic waves
which may cause damage to the human eye or skin if not properly protected. Welding is
essentially the process of unifying two or more pieces of metal at faces rendered plastic or
liquid by heat or by pressure, or by both. In this chapter we shall talk on two types of gas
metal-arc welding processes. Some spectral would then be analysed with respect to the
spectral sensitivity curves in the previous chapter to understand the level of threat they pose to
the unprotected eye.
Generally there arc welding process involves the flow of electrons through an ionised air gap
between an electric circuit and the welding substrate. Due to ionisation, the electrons become
displaced from their mean position with some moving to lower energy levels within the atoms
of the substrate. This change in energy level is characterised by a corresponding release of
energy as electromagnetic waves. The colour intensity of the arc perceived by the human eye
varies according to the frequency of the electromagnetic radiation, which in turn is dependent
on the type of atoms present in the air gap and which varies with different types of gases.
2.3.1 TIG Welding
The generally adopted name for Gas Tungsten-arc welding is TIG welding. In TIG welding an
electric arc is struck between a tungsten electrode and the workpiece, the arc being surrounded
by an inert gas[6]. The electrode may consist of pure tungsten or may be alloyed with
approximately 2% thorium. The arc is initiated through a spark generated by high frequency
voltage across the air gap between the electrode and workpiece. The spark ionises the air gap,
which enables the main arc to be struck without short-circuiting the arc column. The current is
supplied to the electrode via a contact tube within the torch. Filler metal when required is fed
to the arc by separate means.
2.3.2 MIG/MAG Welding
Gas metal-arc welding (MIG/MAG welding) is welding by which an electric arc is struck
between a continuously fed consumable electrode and the work piece[6]. The current is
transferred to the electrode through a contact tube within the welding gun. The contact tube is
connected to the positive pole of the DC circuit. The electrode is continuously fed by means of
an automatic wire drive unit, melts in the arc and is transferred to the weld pool in the form of
droplets.
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2.3.3 Analysis of Some Electromagnetic Spectra with respect to the Sensitivity Curves
In order to give an impression of the variability of the emission spectra of welding arcs in
dependence on the welding material, the shielding gas and the welding current,[7] the
following figures 3 to 6 are shown:
Fig 2.13 Welding arcs [7]
We shall now use the above spectra to understand the meaning of potential hazard level with
respect to the sensitivity weight functions in the previous chapter. Since V (λ) gives the
photopic sensitivity of the eye, that will not be discussed here, since this does not give a
measure of the potential hazard from electromagnetic radiations.
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A) Wavelength Range 300nm to 700nm:
On average, all four spectra show a significant amount of electromagnetic radiations (blue
light) in this region which implies that they pose a potential threat to the unprotected eye. In
this range, figure 4 shows very strong emission spectra when steel is welded with covered
electrodes. Observe that at approximately 440nm (or some small interval for which this point
belongs), the spectral emission is strong enough, hence according to the blue light hazard
response function (chapter 2), they eye is likely to be damaged. The extent of this damage will
be understood more clearly as we go through the chapters ahead. Figure 3 exhibits a line
spectrum in the whole spectral range due to aluminium and magnesium emission, thus
portraying an almost equal radiation level within this range. Because B (λ) drops to zero as we
move away from 440nm, the potential threat will likewise reduce in the same manner, but the
high sensitivity at 440nm makes it a candidate for investigation. Figure 5, shows a slowly
increasing line spectrum. As B (λ) is maximum at approximately 440nm, this implies that they
eye will also be affected by this spectra. And finally figure 6 shows a significant increase in
spectral irradiance at very low wavelengths but drops at we move to 700nm. At 440nm, the
spectral irradiance is low compared to the proceeding wavelengths though still high enough,
and because of the behaviour of B (λ), there is a likely hood of a potential threat, hence should
be investigated.
B) Wavelength Range 380nm to 1400nm:
Similar as in section (A) all four spectra show a significant amount of electromagnetic waves
in this region, thus posing potential hazards threats to the unprotected eye. Figure 4 shows an
initial strong line emission but gradually becomes a line spectrum. According to R (λ) the eyes
has its maximum sensitivity within the approximate range of 435nm to 440nm. And because
this spectrum is significant within this sub interval, it poses a potential threat to the
unprotected eye. The high and almost equal spectral irradiance of figure 3 across the entire
interval and the maximum sensitivity of R (λ) within the subinterval also make it potentially
hazardous to the unprotected eye. Within the subinterval of maximum sensitivity as shown by
R (λ), figures 5 and 6 still stand as potentially dangerous because though within this interval
the spectra is not maximum, it is still high enough to attract attention and a further
investigation.
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2.4 Speedglas and the LC-Technology
2.4.1 Automatic Darkening Welding Filters
Fig 2.14 (a) Welding Helmet Fig 2.14 (b) Filter Unit
Shown above left (fig. 2.14 (a)) is the welding helmet with the filter integrated on it and on the
right (fig. 2.14 (b)) is the filter unit showing the electric circuitry that supplies the external
field to the glass laminate.
This shows a product that utilizes a particular application of LC-Technology. The basic
principle of the filter unit could be described simply as:
Utilizing liquid crystal cells in combination with polarizing sheets (fig. 2.16) to filter
electromagnetic waves. The filtering unit serves as an optical shutter which can be rapidly
switched between a light and a dark state upon application of a stimulating voltage.
The light wave detectors(optical weld detectors), (Fig 2.20 ) positioned around the unit serve
as sensors for the incoming radiation. When incoming radiation is detected by the sensors, the
electric circuit is triggered to produce an electric field which in turn alters the optical
properties of the liquid crystal molecules, thus affecting the transmittance of the unit. In the
absence of any radiation the unit switches back to the light state.
In the place of the conventional fixed shade welding filter which consists of a robust piece of
coloured glass hand-held or fastened in a helmet design in front of the eyes[8], the automatic
darkening welding filter based on LC-Technology is today gaining more grounds in the
welding process. This is because the former has got many limitations, some of which include
the prior adjustment or positioning of the working material. In order for the welder to have a
good vision of the working material, the filter must be moved away from the line of sight.
This movement may pose little or no problem for the hand-held filter, however, filters
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attached to the helmet may achieve this either by having a dual lens with one part possessing a
high optical transmission and the other part being very dark, or by having a lens that can be
pivoted away when not in use. Some limitations with the fixed shade welding filter include:
the welder must change his/her view point of the substrate in order to bring the dark part of
the lens into the line of sight or the usage of one hand to either hold or adjust the equipment
already in place, thereby releasing the work material. One other limitation of these type of
filters is that they are unable to provide complete protection against accidental weld-flush or
the radiation emitted from neighbouring workers as is the case in lager working areas where
several welders and simultaneously based.
Some of the advantages of the automatic darkening welding filter over the conventional fixed
shade welding filter are enumerated below:
This unit is integrated in the helmet and displays a high transmittance level prior to welding;
enabling the operator to position his work correctly. [8]
When the welding arc is ignited, the electronics detect the presence of harmful radiations, and
consequently switches the unit into a pre-set dark protective state within a switching time
around 0.1ms to prevent any eventual eye damage. At the end of which in the absence of
harmful radiations the unit is switched back into the light state for clear vision. The hands also
remain free at all times and the unit sits permanently in place, protecting the welder at all
times.
2.4.1.1 Glass Laminate
A general construction of a liquid crystal cell is shown in the figure 2.15 below. The
thin layer of liquid crystal material sits alternatively between polarizing sheets (fig 2.16)
which in tend sits between two glass plates that are joined together around the edges with a
strong epoxy. The inner surfaces of the plates are coated with a thin transparent conducting
oxide film in order to enable an electric field to be applied across the active crystal layer. By
overlapping the two glass plates such that a small part of the inner surfaces are exposed along
opposite edges, electrical contacts can be made (see fig 2.15).
Fig 2.15 LC-cell
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The figure below shows the layers of the optic glass:
Fig 2.16 Composition of glass laminate (LC-cell) showing the different components
a) LC Cells and Polarisers
As shown on the figure below, depending on the structure of the cell, pure nematic materials
can display induced twisting helixes with both the positive and negative senses of rotation.
However liquid crystal eutectic mixtures are often doped with small quantities of cholesteric
components possessing a natural helical stacking structure with a specific direction of
orientation (fig 2.17). This property defines the spontaneous spiralling direction for the overall
cell and hence prevents the formation of domains or regions of crystal where a reverse twist of
270o occurs instead of the required 90o structure. In the limit of large cell thickness, a helical
structure is capable of rotating the plane of linearly polarised light with nearly 100%
efficiency [8].
The two polarizing sheets are arranged such that they have a angular difference of 90o as
shown on the figure 2.18 b and c below. The sheet on the side of the incident radiation
polarizes the incident light which is then twisted through an angle of 90o by the LC-cell in the
absence of an electric field (fig 2.18 b). This twisted light emerges on the other side of the
glass through the rear polarizing sheet. Notice that there is 100% transmittance of the light that
has been transmitted through the first polarizer and also notice that the arrangement of the
second polarizing sheet corresponds with the path of the twisted light on fig 2.18(b). In the
presence of an applied voltage (fig 2.18 (c)), an external field is created which turn to align the
liquid crystal molecules thereby reducing the twisting effect of the LC cells. This reduction is
in relation to the applied voltage. A minimum twist will occur at a maximum applied voltage
and vice versa. When welding light is detected by the sensors a predefined amount of voltage
LC cells
UV/IR Filter
Polarizers Outer
Protective Plate
Inner Protective Plate
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is applied to the LC cells to give the selected dark shade. Fig 2.18 (c) shows the case where
the twist effect has been completely removed by the external field.
Note that the inner surfaces of the LC glass plates are usually quoted with a very thin layer of
polyimide which is deposited on top of a transparent conducting oxide layer (the oxide layer
covers the two glass plates during manufacturing). This polyimide layer causes the liquid
crystal cells to adhere permanently and align on the surfaces. Thus the external field does not
very much affect the LC cells as you move closer and closer to the glass surfaces.
Fig 2.17 Helical Stacking structure showing twist angle of 900 of the TN cell
Fig 2.18 (b) Behavior of cell in the absence of applied voltage
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Fig 2.18 (c) Behavior of cell when voltage is applied
b) UV/IR Filter
This filter offers permanent protection from ultra violet and Infra Red radiation with a very
high efficiency of almost 100%.
Fig 2.19 UV/IR Filter
The incident IR radiations are permanently reflected as the come into contact with this filter.
Since the filter is permanently in place, the eye is protected at all times. As shown in fig 2.16
it is placed before the first polarizing sheet so that the incident UV/IR radiations are reflected
without any obstruction before the transmitted light is polarized and twisted. Since the other
components are sensitive to heat and also because the liquid crystal molecules are sensitive to
UV light the UV/IR filter is placed in front to prevent any transmission of the UV rays.
Glass substrate
IR light
99.99% reflected/ absorbed
UV light 99.9997%absorbed/reflected by UV/IR
filter and polarising filters
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2.4.1.2 Electronic Circuitry
Fig 2.20 Electronic circuitry connected to the glass laminate
Above is a picture of the electronic circuitry connected to the glass laminate through the wires.
The controlling electronics have the function of detecting whether or not welding is in process
and to apply the appropriate voltages to the liquid crystal cells present in the glass laminate. In
principle the electronics consist of 3 parts; the detectors that take in information from the
environment, the logic circuit that makes decisions depending upon the input information and
the power supply that operates the system and is connected or disconnected from the cell.
The most basic control components of the electronic circuit is the A and NA (negative-A)
terminals connected to the A-cells in the glass laminate. As shown on the square waveform
graph below, in the light state, the voltage drop across the LC cells is zero. When the optical
weld detectors, detect the presence of radiation, information is sent to the logic circuit, which
in turn inputs a very fast and high voltage of about 40V across the glass laminate lasting for a
period of about 4ms.This high voltage serves as the voltage required for a fast switching from
the light state to the dark state. Immediately after the initial peak voltage, the LC cells are
discharged and are then driven with a low DC-voltage that reverses polarity with a periodicity
of 12ms.
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After the switch from the light state to the dark state, the voltage amplitude at A now drops to
a lower steady value (in this case we consider 3.5V) as shown on the first graph and an
approximate wave periodicity of 24ms.
Note: that for a darker state after switching has occurred, the steady amplitude voltage value
would be greater and vice versa.
At the same time as shown on the second graph the voltage drop across the NA terminal is 0V
from the light state until after the A-cells have been completely discharged. From this point
onwards (within the dark state) the voltages across the NA-terminal continues with the same
steady amplitude and frequency as that of the A-terminal but completely out of phase and
reversed polarity.
In the absence of radiation the voltage across both terminals fall back to zero and the glass
laminate becomes transparent again. This cycle continues every time in the welding arc is
ignited.
Note
1) Observe that for the first two graphs the voltage is either zero or greater than zero, because
the observation is done independently from a grounded terminal which is common to both the
A and NA terminals
2) The last graph shows a superposition of the voltage drop across the A and NA terminals,
which shows the way the voltage is fed across the LC cells alternatively. Observe that with a
DC-supply, the voltage it made to reverse polarity, thus behaving like an AC source (thanks to
the parallel connection between the A and NA terminals. This intermediate reversing in
polarity is important to prevent any eventual sticking of the LC molecules or ions which may
be present in the cell.
3) The first graph shows a lag in time of about 4ms. This does not mean that the switching
occurs 4ms after the welding arc is ignited, but rather shows an initial time when the welding
arc has not yet been ignited. Within this time the glass laminate is in the light or transparent
state. The actual ignition of the welding arc occurs at 4ms at which time the 40V is fed into
the A-terminal for immediate switching.
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Fig 2.21 (a)Above: Voltage drop across A-Terminal; Below: Voltage drop across NA-
Terminal
Fig 2.21 (b) Voltage drops across A and NA terminals plotted on the same axes.
Voltage/Time
0
2
4
6
8
10
0 8 16 24 32 40 48 56 64 72 80 88
T(ms)
Voltage(V
)
NA [V]
Voltage/Time
0
5
10
15
20
25
30
35
40
45
0 8 16 24 32 40 48 56 64 72 80 88T(ms)
Voltage (V
)
A [V]
Light State Dark State
4ms
4ms
Voltage/Time
-10
-5
0
5
10
15
20
25
30
35
40
45
0 8 16 24 32 40 48 56 64 72 80 88
T(ms)
Vo
ltag
e(V
)
A [V]
NA[V]
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2.4.1.3 Switching Time
Making use of the proper definition of the switching time applied to automatic darkening
welding filters[9], the switching time stipulated in eqn. 4 transforms to:
t(ζ=3*ζd)
Ts = (1/ζ1)* ∫ζ(t) dt (8)
t=0
Where ζ d = transmittance at the dark state
ζ l = transmittance in the light state
Normally the application of the above formula could be described according to the picture
below(fig 4.9 applied to a welding filter with different shades):
Page 3
50-300 ms0,1 ms
Fig 2.22 Switching time sequence
As depicted in the picture above the numbers show the different shades of the product. Shade
5-6 are the offset shades i.e. when the product is not in use. When the product is switched on,
the shade moves to the light state (the pictures below each region shows how the welder
perceives his/her object). When the welding light is ignited the product switches to a pre-set
dark state between 9 and 13 within an approximate switching time of 0.1ms. During this time
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the welder is completely protected from harm. When the welding arc is switched of, the
product then switches back to the light state with a switching time between 50-300ms.
If the filter fails to switch we say that switching failure has occured. Examples of situations
that might result in switching failure include the following:
• Wrong setting of parameters by the user
• Detectors being hidden from the welding arc
• Low battery
• Poor detector functionality
Note: For the purpose of this project 0.5s of switching failure was considered in the
investigation. This was because the blink reflex is often mentioned as 0.25 s, hence 0.5 s gives
some error margin. However, if the welding filter fails to switch several times, a longer time
perhaps should be considered.
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3 Execution
3.1 Comparison of Different Standards
3.1.1 Introduction
Recent developments in biological research, has shown that the initial maximum permissible
exposure (MPE) limits for protection of workers from risks associated with artificial optical
radiations were more stringent than they really should have been. These restrictions which
were stipulated in the 1999 Technical Report of the International Electro technical
Commission (IEC) [10] were more restrictive than the most recent investigated permissible
exposure limits of the eyes [5]. As a result of which this comparative study was carried out
between the 1999 Technical Report, 2007 IEC International Standard [11] and the 2006
Directive of The European Parliament and of The Council of 5th April 2006 to show clearly,
the extent to which they differ.
The conclusions drawn from this study were as a result of comparing the MPE limits of the
exposure of the eyes to harmful radiations within the wavelength range from 180nm to
1400nm for both incoherent and coherent sources of radiation irradiating the eyes.
The technique employed was analytic and graphical where the MPE’s from both documents
were either analyzed mathematically or plotted graphically against exposures times between
10-9s to 3x104s for incoherent sources and 10-13 s to 3x104 s for coherent sources, and
analyzed to come out with logical conclusions.
The tool used in this analysis was Microsoft Excel program.
Unless otherwise stated the terms and formulae used in this analysis remain the same as those
used in the 2006 Directive, the 1999 IEC Technical Report and the 2007 IEC International
standard
The main assumption which was made in this study (unless otherwise stated) was that, where
ever possible within each sub interval of comparison, the minimum MPE of the 2006
Directive was compared with the maximum possible MPE of the 1999 Technical report. Also
the size of the object illuminating the eye was considered to be a point source.
Here the analysis shall begin with the incoherent radiation MPE’s followed by the analysis of
the coherent radiation MPE’s.
Note: Since only the incoherent part of the radiations is harmful to the eyes it is expected that
the same conclusion be drawn for the case of coherent radiations.
The comparison will be done using any of the following quantities in different time intervals:
Effective Irradiance, radiant exposure, effective radiant exposure, effective radiance etc.
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3.1.2 Comparison Between the Incoherent MPEs of the 1999 Technical
Report and 2006 Directive
Incoherent radiations are wave packets consisting of radiations with phase differences (out of
phase) and/or with different frequencies. Here the comparison will be done starting from the
smallest wavelength (180nm) progressively to 1400nm. Graphical analysis will only be used
in wavelength ranges which pose remarkable differences in their MPE’s, otherwise simple
logical explanations will be used to illustrate differences and/or similarities.
a) Wavelength Range 180nm to 400nm:
Source
Documen
t
Quantity and
Weighting
Function
Wavelength
(nm)
Exposure
limit value
Units Part of the
body
Hazard
IEC-1999
400nm
Heff=∑H(λ)S(λ)∆λ
180nm
180-400
(UVA,UVB
and UVC)
Heff = 30
Daily value 8
hours
[Jm-2]
Eye cornea
Conjunctiva
Lens
skin
Photokeratitis
conjunctivitis
cataractogenesis
erythema
elastosis
skin cancer
Directive
-2006
Table 1
The quantity and weighting function used in both documents are the same and the MPE is
given in terms of the effective radiance (Heff) spectrally weighted by S (λ) which is
dimensionless and takes into account the wavelength dependence of the health effects of UV
radiation on eye and skin.As shown on table 1, the MPE’s for both documents are the same
with a maximum permissible radiant exposure limit of 30 Jm-2. Hence Heff=30 Jm-2 for the
entire time interval from 10-9s to 3x104s and equal in both documents.
Conclusion; in this wavelength interval both documents specify equal exposure limits.
b) Wavelength Range 315nm to 400nm;
Source
document
Quantity and
Weighting
Function
Wavelengt
h (nm)
Exposure
limit value
Units Part of the
body
Hazard
IEC-1999
400nm
HuvA=∑H(λ)∆λ
315nm
315-400
(UVA)
HUVA = 104
Daily value 8
hours
[Jm-2]
Eye Lens
cataractogenesis
Directive
-2006
Table 2
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The quantity and waiting function used in both documents are the same and the MPE is given
in terms of the radiant exposure (HUVA), the time and wavelength integral or sum of the
radiance within the UVA wavelength range 315nm to 400nm.
As shown on table 2, the MPE’s for both documents were the same with a maximum
permissible radiant exposure limit of 40 Jm-2. Hence HUVA=40 Jm-2 for the entire time interval
from 10-9s to 3x104s.
Conclusion; in this wavelength interval both documents specify equal exposure limits.
c) Wavelength Range 300nm to 700nm:
Source
document
Quantity and
Weighting
Function
Wavelength
(nm)
Exposure
limit value
Units Part of
the body
Hazard
IEC-1999
700nm
LB=∑L(λ)B(λ)∆λ
300nm
300-700
Blue light
LB=106 /t
for t≤10000s
LB:
[Wm-2 sr-1]
Eye
retina
photo retinitis LB=100
for t>10000s
Directive-
2006
LB=106 /t
for t≤10000s
LB=100
for t>10000s
Table 3
Note: 1) For source document Directive-2006, the angular subtense (α) made by the object’s
image on the eye has been considered to be α ≥ 11mrad.
2) The range of 300nm to 700nm covers part of the UVB, all UVA and most of visible
radiation; however, the associated hazard is commonly referred to as ‘blue light’ hazard. Blue
light strictly speaking covers only the range of approximately 400nm to 490nm. [5]
The quantity and weighting function used in both documents are the same with the MPE
given in terms of the effective radiance (LB) of blue light, spectrally weighted by B(λ), which
is dimensionless and takes into account the wavelength dependence of the photochemical
injury caused to the eye by blue light radiation. The MPE’s for both documents given in terms
LB were the same with a maximum permissible radiant exposure limit distributed as shown on
table 3:
For exposure times (t) less than 10,000 seconds, LB = 106/t and for times (t) greater than
10,000 seconds the LB = 100.
Conclusion; in this wavelength interval both documents specify equal exposure limits
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d) Wavelength Range 380nm to 1400nm:
Source
document
Quantity and
Weighting Function
Wavelength
(nm)
Exposure limit
value
Units Part of
the body
Hazard
IEC-1999
1400nm
LRTH=∑L(λ)B(λ)∆λ
380nm
380-1400
Visible &
IRA
LR=41,2/(Cα.t0.9)
t≤1,8x10-5 s
LR:
[Wm-2 sr-
1]
Eye
retina
Retinal burn
LR=5.104/ (Cα.t1/4)
1,8x10-5s < t≤10s
LR=2,8.104/Cα
t>10s
Directive-
2006
LR=8,89.108/Cα
t<10µs
LR=5.107/(Cα t0,25)
10µs<t≤10s
LR=2,8.107/Cα
t>10s
Table 4
Where Cα is a correction factor describing the dependence of the MPEs on the source size.
Note: 1) For IEC-1999, Cα is taken to be Cα=1.5 so that the LR expressions would give the
maximal possible curve while for the Directive-2006 Cα=100 for a minimal possible curve (in
conformity with the assumption made in the introduction).
In this range it was observed that the formulae describing the MPEs in both documents were
the same, but they changed with different time intervals as shown on table4. As a result of
which these formulae were plotted in the Excel work sheet, resulting in the graphical
representations below (fig 3.1).
The quantity and weighting function used in both documents are the same and the MPE given
in terms of effective radiance (LR) for thermal injury, spectrally weighted by R(λ), which is
dimensionless and takes into account the wavelength dependence of the thermal injury caused
to the eye by visible light and IRA radiation.
As shown on figure 3.1 below, the MPE as described by the formulae given in the 1999 IEC
Technical Report is indicated with blue curve and that described by the formulae given in the
2006 Directive is indicated with red curve.
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From observation it can be seen that the Red line offers a higher maximum permissible
exposure limit. That is for corresponding exposure times the red curve offers greater exposure
limits.
As a conclusion, the 2006 Directive offers a much higher MPE limit than the 1999 IEC
Technical report.
Incoherent MPE(380nm-1400nm)
-100000
100000
300000
500000
700000
900000
1100000
1300000
1500000
0 5 10 15 20
Exposure time (t/s)
Re
tin
al T
he
rma
l
Ha
za
rd(L
rth
)
IEC-1999Directive-2006
Fig. 3.1
Note: In evaluating the functions describing the MPE values in both documents, it was
observed that the formulae were inversely proportional to the limiting angular subtense of the
eye (Cα ) . As a result of which to obtain the maximum possible MPE of the 1999 IEC
Technical report the smallest Cα was used which was equal to Cα=1.5 mrad across the
entire time interval. The assumption made in using this value for Cα was that the dependence
of the minimum angular subtense on the exposure duration due to the time dependence of eye
movements is less than 0.7s (time<0.7s).
Likewise to obtain the minimum possible MPE of the 2006 Technical Report the maximum
possible Cα was used, which was equal to Cα=100mrad across the entire time interval.
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e) Wavelength Range 780nm to 1400nm:
Source
document
Quantity and
Weighting Function
Wavelength
(nm)
Exposure limit
value
Units Part of
the body
Hazard
IEC-1999
1400nm
LRTH=∑L(λ)B(λ)∆λ
780nm
780-1400
IRA
LR=41,2/(Cα.t0.9)
t≤1,8x10-5s
LR:
[Wm-2sr-1]
Eye retina
Retinal burn
LR=5.104/ (Cα.t1/4)
1,8x10-5s < t≤10s
LR=6000/Cα
t>10s
Directive-
2006
LR=8,89.108/Cα
t<10µs
LR=5.107/(Cα t0,25)
10µs<t≤10s
LR=6.106/Cα
t>10s
Table5
Note: See note under table 4.
Similarly with the preceding range, in this range it was observed that the formulae describing
the MPE’s were the same for both documents but they changed with different time intervals
(table5), as a result of which these formulae were plotted in the Excel work sheet, resulting in
the graphical representations below (fig 3.2).
The quantity and weighting function used in both documents are the same and the MPE given
in terms of effective radiance (LR) for thermal injury, spectrally weighted by R(λ), which is
dimensionless and takes into account the wavelength dependence of the thermal injury caused
to the eye by visible light and IRA radiation.
As shown on figure 3.2 below, the MPE as described by the formulae given in the 1999 IEC
Technical Report is indicated by blue curve and that described by the formulae given in the
2006 Directive is indicated by red curve.
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From observation it can be seen that, the red curve offers a higher maximum permissible
exposure limit.
As a conclusion, the 2006 Directive offers a much higher MPE limit than the 1999 IEC
Technical report.
Incoherent MPE(780nm-1400nm)
-100000
100000
300000
500000
700000
900000
1100000
1300000
1500000
0 5 10 15 20
Exposure time (t/s)
Eff
ec
tiv
e IR
Ra
dia
nc
e (
Lir
)
IEC-1999
Directive-2006
Fig. 3.2
Note: In evaluating the functions describing the MPE values in both documents, it was
observed that the formulae were inversely proportional to the limiting angular subtense of the
eye (Cα). As a result of which to obtain the maximum possible MPE of the 1999 IEC
Technical report the smallest Cα was used which was equal to Cα=1.5mrad across the
entire time interval. The assumption made in using this value for Cα was that the dependence
of the minimum angular subtense on the exposure duration due to the time dependence of eye
movements is less than 0.7s (time<0.7s).
Likewise to obtain the minimum possible MPE of the 2006 Technical Report the maximum
possible Cα was used, which was equal to Cα=100mrad across the entire time interval.
f) Conclusion
From the above analysis it can be concluded that on average and in most of the exposure time
interval compared above the 2006 Directive gives an overall higher MPE scale that the more
stringent 1999 IEC Technical report.
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The next step now will be to analyze the results of the coherent radiations sources.
3.1.3 Comparison Between the Coherent MPEs of the 2007 IEC
International Standard and the 2006 Directive
Coherent optical radiations are wave packets consisting of radiations in phase. As it was the
case with the non-coherent radiations, here comparison will be done beginning from the
smallest wavelength (180nm) progressively to 1400nm. Graphical analysis will only be used
in wavelength ranges which pose remarkable differences in their MPE’s, otherwise simple
logical explanations will be used to illustrate differences and/or similarities. The comparison
will be done between the 2006 Directive and the IEC 2007 Directive.
a) Wavelength Range 180nm to 303nm:
This wavelength range will be divided in 2 parts. The first part will range from 180nm to 280
and the second part will range from 280nm to 302nm because they constitute UVC and UVB
respectively.
i) 180nm to 280nm (UVC): The MPEs in both reports were calculated in terms of radiant
exposure(H) and the equivalent irradiance(E). For exposure times less than 10-9 s, the
irradiance MPE in both reports was given as E=3x104Wm-2 , while for times greater than 10-9
s, the radiant exposure MPE limit was given as H=30Jm-2. We see here that both reports give
the same MPEs in this range.
Source Document Wavelength (nm) Duration(s)
10-13-10-9 10-9-3x104
IEC-2007 180-280
UVC
E=3x1010[Wm-2] H=30[Jm-2]
Directive-2006
Table 6
ii) 280nm to 302.5nm (UVB):
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As was the case in the previous wavelength interval, the MPEs in both reports were calculated
in terms of radiant exposure (H) and the equivalent irradiance (E). For exposure times less
than 10-9 s, the irradiance MPE in both reports was given as E=3x104Wm-2, while for times
greater than 10-9 s, the radiant exposure MPE limit was given as H=30Jm-2. We see here that
both reports still give the same MPEs in this range.
Source Document Wavelength (nm) Duration(s)
10-13-10-9 10-9-3x104
IEC-2007 280-302.5
UVB
E=3x1010[Wm-2] H=30[Jm-2]
Directive-2006
Table7
b) Wavelength Range 302.5nm to 315nm:
MPE IEC-2007 table
Wavelength (nm) Exposure time (s)
10-13 – 10-9 10-9 – 10 10 – 3x104
302,5 to 315
E=3x1010
[Wm-2]
Photochemical Hazard
(t>T1) H=C2 [Jm-2]
Thermal Hazard
(t≦T1) H=C1 [Jm-2]
H=C2 [Jm-2]
Table 8
MPE Directive 2006 table
Wavelength (nm) Exposure time (s)
10-13 – 10-9 10-9 – 10 10 – 3x104
303
H=40 [Jm-2]; if t<2,6x10-9 then H=5,6x103t0,25 H=40 [Jm-2]
304 H=60 [Jm-2]; if t<1,3x10-8 then H=5,6x103t0,25 H=60 [Jm-2]
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305
E=3x1010
[Wm-2]
H=100 [Jm-2]; if t<1,0x10-7 then H=5,6x103t0,25 H=100 [Jm-2]
306 H=160 [Jm-2]; if t<6,7x10-7 then H=5,6x103t0,25 H=160 [Jm-2]
307 H=250 [Jm-2]; if t<4,0x10-6 then H=5,6x103t0,25 H=250 [Jm-2]
308 H=400 [Jm-2]; if t<2,6x10-5 then H=5,6x103t0,25 H=400 [Jm-2]
309 H=630 [Jm-2]; if t<1,6x10-4 then H=5,6x103t0,25 H=630 [Jm-2]
310 H=103 [Jm-2]; if t<1,0x10-3 then H=5,6x103t0,25 H=1,0x103 [Jm-2]
311 H=1,6x103[Jm-2]; if t<6,7x10-3 then H=5,6x103t0,25 H=1,6x103 [Jm-2]
312 H=2,5x103[Jm-2]; if t<4,0x10-2 then H=5,6x103t0,25 H=2,5x103 [Jm-2]
313 H=4,0x103[Jm-2]; if t<2,6x10-1 then H=5,6x103t0,25 H=4,0x103 [Jm-2]
314 H=6,3x103[Jm-2]; if t<1,6x100 then H=5,6x103t0,25 H=6,3x103 [Jm-2]
Table 9
To show that the MPE limits specified by both documents are equal it suffices to show that
both tables specify equal MPE limits and this will be done by using the first table to derive the
values of the second, using Microsoft excel. Observe that the MPE specified by the second
columns in both documents are equal hence it is left to show the equality in the last 2 columns.
First we shall start by showing that the upper bound specified for values of t in the second
table is the same as the T1 in table 1:
From IEC-2007 Directive the expression for T1= 100,8(λ – 295)x 10-15s
For each wavelength, this evaluates to:
λ T1
303 2,51189E-09
304 1,58489E-08
305 0,0000001
306 6,30957E-07
307 3,98107E-06
308 2,51189E-05
309 0,000158489
310 0,001
311 0,006309573
312 0,039810717
313 0,251188643
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314 1,584893192
Table 10
Which evaluates to the boundary values of t as shown on the second table. Looking now at the
expression, from IEC-2007 , C1= 5,6x103t0,25 which is equal to the expression for H in the
second table.
Finally from IEC-2007 the expression for C2=100,2(λ-295). Using excel this evaluates according
to the table below:
λ C2
303 39,81072
304 63,09573
305 100
306 158,4893
307 251,1886
308 398,1072
309 630,9573
310 1000
311 1584,893
312 2511,886
313 3981,072
314 6309,573
Table 11
Observe that these values are either equal to or very close to the values on the second table.
The difference is probably because of precision differences else they should be the same.
It has been shown that both tables are equal since we can derive one from the other, hence
they specify equal MPE limits.
c) Wavelength Range 315nm to 400nm (UVA):
Source
Document
Wavelength
(nm)
Duration(s)
10-13-10-9 10-9-10 10-3x104
IEC-2007 315-400
UVA
E=3x1010[Wm-2] H=5,6x103t0,25
[Jm-2]
H=104[Jm-2]
Directive-2006
Table 12
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In this range the MPEs for both reports were calculated in terms of the radiant exposure (H)
for times greater than 10-9s and in terms of the irradiance (E) for times less than 10-9s. The
formulae used in these calculations for both report were the same and the distribution of the
MPE for different exposure times was as follows:
E=3x1010Wm-2 for times less than 10-9s and H=5.6x103t0,25 for exposure times between 10-9s
and 10s and for the rest of the exposure time, H=104Jm-2. It can be observed that the MPEs
stipulated by both reports are the same.
d) Wavelength Range 400nm to 700nm (Visible Light and IRA):
In this range the MPEs were compared in terms of radiant exposure (H) for the entire time
interval. Within this interval, the IEC range was subdivided into 4 subintervals (where
variations were observed in the MPE values) given as follows:
i) 400nm to 450nm
ii) 450nm to 500nm
iii) 500nm to 600nm
iv) 600nm to 700nm
i) 400nm to 450nm
Source
Document
Duration(s)
10-13-10-11 10-11-10-9 10-9-
1,8x10-5
1,8x10-5-10 10-102 102-104 104-3x104
IEC-2007 H=1,5x10-4
[Jm-2] H=2,7x104t0,75 [Jm-
2]
H=5x10-3
[Jm-2]
H=18t0,75
[Jm-2]
H=100
[Jm-2]
E=C3 [Wm-2]
Directive-
2006
H=1,5x10-
4CE [Jm-2]
H=2,7x104t0,75CE
[Jm-2]
H=5x10-3
CE[Jm-2]
H=18t0,75CE
[Jm-2]
H=100CB
[Jm-2]
α=110
E=1CB
[Wm-2]
α=1,1t0,5
E=1CB
[Wm-2]
α=110
Table 13
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Where α= angular subtense of the eye expressed in mrads. To draw any conclusion here, we
need the values for
CB, CE and C3 in this wavelength interval.
From IEC-2007, C3=1,0. From Directive-2006, CB=1,0 and CE=1,0. Hence MPEs from both
documents are equal since their expressions simplify to the same expressions.
ii) 450nm to 500nm:
Source
Document
Duration(s)
10-13-10-11 10-11-10-9 10-9-
1,8x10-5
1,8x10-5-10 10-102 102-104 104-3x104
IEC-2007 H=1,5x10-4
[Jm-2] H=2,7x104t0,75 [Jm-
2]
H=5x10-3
[Jm-2]
H=18t0,75
[Jm-2]
H=100C3
[Jm-2]
E=C3 [Wm-2]
Directive-
2006
H=1,5x10-
4CE [Jm-2]
H=2,7x104t0,75CE
[Jm-2]
H=5x10-3
CE[Jm-2]
H=18t0,75CE
[Jm-2]
H=100CB
[Jm-2]
α=110
E=1CB
[Wm-2]
α=1,1t0,5
E=1CB
[Wm-2]
α=110
Table 14
Where α= angular subtense of the eye expressed in mrads. To draw any conclusion here, we
need the values for
CB, CE and C3 in this wavelength interval.
From IEC-1999, C3=100,02(λ-450) . From Directive-2006, CB=10 0,02 (λ-450) and CE=1,0. Hence
MPEs from both documents are equal since their expressions simplify to the same
expressions.
iii)500nm to 600nm:
Source
Document
Duration(s)
10-13-10-11 10-11-10-9 10-9-
1,8x10-5
1,8x10-5-10 10-102 102-104 104-
3x104
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IEC-2007 H=1,5x10-4
[Jm-2] H=2,7x104t0,75
[Jm-2]
H=5x10-3
[Jm-2]
H=18t0,75
[Jm-2]
E=10 [Wm-2]
Directive-
2006
Thermal
Retinal
Damage
H=1,5x10-4CE
[Jm-2]
H=2,7x104t0,75CE
[Jm-2]
H=5x10-3
CE[Jm-2]
H=18t0,75CE
[Jm-2]
E=10 [Wm-2]
Photochemical
Retinal
damage
H=100C
B [Jm-2] α=110 or
E=1CB [Wm-
2]
E=1CB
[Wm-
2]
α=1,1t0
E=1CB
[Wm-2]
α=110
Table 15
Here the MPE limit value given for IEC-2007 is equal to the thermal retinal injury MPE given
for Directive-2006. Observe that for the photochemical retinal hazard, the expressions
describing the limiting values for Directive-2006 differ from the constant value as stipulated
in IEC-2007. To understand the difference a mathematical analysis is done as shown below:
The MPE limit of IEC-2007 gives E=10 [Wm-2]
Looking now at the expression given by Directive-2006 we have E=1CB
But CB=10 0,02 (λ – 450 )
Where λ=wavelength. CB is an exponential function of λ. It suffices therefore to take the
lower bound λ=500 and the upper bound λ=600 to get the minimum and maximum CB values
and hence the range of MPE limit values.
For λ=500, CB=10 and hence E=10 [Wm-2]
For λ=600, CB=100 and hence E=1000 [Wm-2]
Hence for this wavelength interval, the minimum MPE limit which corresponds to that obtain
when λ=500 is equal to 10 [Wm-2], which implies that every other MPE limiting value within
this range ≥10 [Wm-2]. Comparing this range with the limiting value E=10 [Wm-2] for the
thermal retinal damage and because the most restrictive of all limiting values applied within
an interval is considered, it is logical to consider the limiting value in this case to be E=10
[Wm-2]. Observe that this conclusion makes the limiting value equal to that specified by IEC-
2007.
Hence a logical conclusion here would be that the limiting values for both documents are
equal.
iv)600nm to 700nm
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Source
Document
Duration(s)
10-13-10-11 10-11-10-9 10-9-
1,8x10-5
1,8x10-5-10 10-102 102-
104
104-3x104
IEC-2007 H=1,5x10-4
[Jm-2] H=2,7x104t0,75
[Jm-2]
H=5x10-3
[Jm-2]
H=18t0,75
[Jm-2]
E=10 [Wm-2]
Directive-
2006
H=1,5x10-
4CE [Jm-2]
H=2,7x104t0,75CE
[Jm-2]
H=5x10-3
CE[Jm-2]
H=18t0,75CE
[Jm-2]
E=10 [Wm-2]
Table 16
CE=1,0 for point sources. The hazard studied in this wavelength region is the Thermal Retinal
Damage. The observation made here is that expressions describing the MPEs are the same,
hence specifying equal limiting values.
e) Wavelength Range 700nm to 1400nm (Visible Light and IRA):
Due to many variations in the parameters this interval will be divided into 4 subintervals for
comparison.
1)700nm- 1050nm:
Source
Document
Wavele
ngth
(nm)
Duration(s)
10-13-10-11 10-11-10-9 10-9-1,8x10-5 1,8x10-5-10 10 - 3x104
IEC-2007 700-1050
Visible
& IRA
H=1,5x10-4C4
[Jm-2]
H=2,7x104t0,75C4 [Jm-2] H=5x10-3C4
[Jm-2]
H=18t0,75C4
[Jm-2]
E=10C4C7
[Wm-2]
Directive-
2006
H=1,5x10-4CACE
[Jm-2]
H=2,7x104t0,75CACE
[Jm-2]
H=5x10-
3CACE [Jm-2]
H=18t0,75CACE
[Jm-2]
E=10CACC
[Wm-2]
Table 17
In this range the MPE is expressed in terms of the radiant exposure (H) and the irradiance (E).
Here the formulae will be compared to see if the result to the same conclusion.
First we check if for these intervals the following are true:
i) C4= CACE
ii) C4C7=CACC
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i) C4= CACE:
From IEC-1999, C4=100,002(λ-700)
From 2006-Directive, CA=10 0,002(λ-700) and CE=1,0 (using point sources) This implies that
CA*CC=100,002(λ-700)=C4 Hence (i) is true.
ii) From IEC-2007 C7=1 which implies that C4C7= 100,002(λ-700)
Also from Directive-2006, CC=1,0 which implies that CACC=10 0,002(λ-700)=C4C7
The above derivation clearly shows that these correction factors are the same for both
documents hence all formulae are the same. Here we conclude that both documents specify the
same MPE limits.
2)1050nm-1150nm:
Source
Docume
nt
Wavelen
gth (nm)
Duration(s)
10-13-10-11 10-11-10-9 10-9-5x10-5 5x10-5-10 10 - 3x104
IEC-
2007
1050 - 1150
Visible &
IRA
H=1,5x10-4C7
[Jm-2]
H=2,7x104t0,75C7
[Jm-2]
H=5x10-3C7
[Jm-2]
H=90t0,75C7
[Jm-2]
E=10C4C7
[Wm-2]
Directive
-2006
H=1,5x10-3CCCE
[Jm-2]
H=2,7x103t0,75CCCE
[Jm-2]
H=5x10-2CCCE
[Jm-2]
H=90t0,75CCCE
[Jm-2]
E=10CACC
[Wm-2]
Table 18
In this range the MPE is expressed in terms of the radiant exposure (H) and the irradiance (E).
Here the formulae will be compared to see if the result to the same conclusion.
First we check if for these intervals the following are true:
i) C7= CcCE
ii) C4C7=CACC
i) C7= CcCE:
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From IEC-1999, C7=1
From 2006-Directive, Cc=1,0 and CE=1,0 (using point sources) This implies that
CE*Cc=1,0=C7 Hence (i) is true.
ii) From IEC-2007 C4=5 which implies that C4C7= 5
Also from Directive-2006, CA=5,0 which implies that CACC=5=C4C7
The above derivation clearly shows that these correction factors are the same for both
documents hence all formulae are the same. Here we conclude that both documents specify the
same MPE limits.
3)1150nm-1200nm:
Source
Document
Wavelength
(nm)
Duration(s)
10-13-10-11 10-11-10-9 10-9-5x10-5 5x10-5-10 10 - 3x104
IEC-2007 1150 - 1200
Visible &
IRA
H=1,5x10-4C7
[Jm-2]
H=2,7x104t0,75C7
[Jm-2]
H=5x10-
3C7 [Jm-2]
H=90t0,75C7
[Jm-2]
E=10C4C7
[Wm-2]
Directive-
2006
H=1,5x10-
3CCCE [Jm-2]
H=2,7x103t0,75CC
CE [Jm-2]
H=5x10-
2CCCE [Jm-
2]
H=90t0,75CC
CE [Jm-2]
E=10CACC
[Wm-2]
Table 19
In this range the MPE is expressed in terms of the radiant exposure (H) and the irradiance (E).
Here the formulae will be compared to see if the result to the same conclusion.
First we check if for these intervals the following are true:
i) C7= CcCE
ii) C4C7=CACC
iii) C7= CcCE:
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From IEC-2007, C7=100,018(λ-1150)
From 2006-Directive, Cc=100,018(λ-1150) and CE=1,0 (using point sources) This implies that
CECc=100,018(λ-1150) =C7 Hence (i) is true.
ii) From IEC-2007 C4=5 which implies that C4C7= 5x100,018(λ-1150)
Also from Directive-2006, CA=5,0 which implies that CACC=5x100,018*(λ-1150)
The above derivation clearly shows that these correction factors are the same for both
documents hence all formulae are the same. Here we conclude that both documents specify the
same MPE limits.
4)1200nm-1400nm:
Source
Document
Wavelengt
h (nm)
Duration(s)
10-13-10-11 10-11-10-9 10-9-5x10-5 5x10-5-10 10 - 3x104
IEC-2007 1200 -
1400
Visible &
IRA
H=1,5x10-4C7
[Jm-2]
H=2,7x104t0,75C7
[Jm-2]
H=5x10-3C7
[Jm-2]
H=90t0,75C7
[Jm-2]
E=10C4C7
[Wm-2]
Directive-
2006
H=1,5x10-3CCCE
[Jm-2]
H=2,7x103t0,75CCCE
[Jm-2]
H=5x10-2CCCE
[Jm-2]
H=90t0,75CCCE
[Jm-2] E=10CACC
[Wm-2]
Table 20
In this range the MPE is expressed in terms of the radiant exposure (H) and the irradiance (E).
Here the formulae will be compared to see if the result to the same conclusion.
First we check if for these intervals the following are true:
i) C7= CcCE
ii) C4C7=CACC
iii) C7= CcCE:
From IEC-2007, C7=8
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From 2006-Directive, Cc=8 and CE=1,0 (using point sources) This implies that CECC=8 =C7
Hence (i) is true.
ii) From IEC-2007 C4=5 which implies that C4C7= 5x8=40
Also from Directive-2006, CA=5,0 which implies that CACC=5x8=40=C4C7
The above derivation clearly shows that these correction factors are the same for both
documents hence all formulae are the same. Here we conclude that both documents specify the
same MPE limits.
3.1.4 Conclusion from Complete Analysis
To give a final conclusion to the above analysis of all documents, we see that the 2007 IEC
document and the 2006 Directive specify equal MPE limits for coherent sources while the
2006 Directive specifies a greater MPE limit than that specified by the 1999 IEC Technical
report, hence we shall employ the 2006 Directive for further analysis in this project.
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3.2) Study of Filter Characteristics
In order to be able to investigate harm that may be caused to the eyes if not properly protected,
it is necessary to understand how the filter works.
Here we shall study the filter characteristics by measuring the transmittance ζ(λ) of two
different shades in the wavelength range 380nm to 780nm.
From these measurements, we shall then obtain the luminous transmittance (T) [12, 13] for
each shade using the formula (9)
780nm 780nm
T= [∑ V(λ).S(λ).ζ(λ) ∆λ / ∑ V(λ).S(λ).∆λ] (9)
380nm 380nm
Where V(λ) = Luminous efficiency function for daylight
ζ(λ) = measured spectral transmittance of the filter
S(λ) = Spectral distribution of radiation of CIE standard illuminant A
After obtaining the luminous transmittance T, we shall then use it to calculate the
corresponding shade number S [7,9] using the formulation(10):
S= 1- (7/3).Log(T) (10)
We are now prepared to understand the level of protection we can obtain from each shade
number.
Question?
What amount of incident luminance can we use the obtained luminous transmittances to
reduce it to a comfortable level?
Answer:
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If Lw [7,9] is the luminance of the incident spectrum then we require a luminous transmittance
T (according to eqn. 11) to reduce it to a comfortable level.
In other words we can interpret (11) as: a luminous transmittance (T) of the filter will reduce
the incident spectrum to a comfortable level for all incident spectrum with luminance less than
or equal to (730/T)
Lw = 730 / T (cdm-2
) (11)
We are now we equipped to work with sample data:
Consider table 21 (see annex):
The Luminous transmittance obtained from the measured transmittance of both states denoted
T3 and T13 were calculated from table according to (9) and the corresponding shade numbers
S3 and S13 according to (10) to obtained the following:
T3 = 0,113224465 S3 = 3,207473
T13 = 4,79E-06 S13 = 1,34E+01
To know the incident luminance (Lw) for which these transmittances can give a comfortable
level of luminance we use (11).
According to (11) the incident luminance on the filter for which corresponding transmittances
can protect the eyes will be:
T3 = 0,113224465 Lw = 6447,369808 cdm-2
T13 = 4,79E-06 Lw = 1,52E+08 cdm-2
Hence for Lw = 6447,369808, the eye would be comfortable by using T3 = 0,113224465
Similarly for Lw = 1,52E+08, the eye would be comfortable by using T13 = 4,79E-06
This is clearly represented on the table 22 below:
Description Shade Number (S) Transmittance (T) Incident
Luminance(cdm-2
)
Light state
3,207473 0,113224465 6447,369808
Dark state
1,34E+01 4,79E-06 1,52E+08
Table 22
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The above table could be extended to comprise of all the shades and transmittances as shown
on the table 23 below:
Shade
T
Incident
Luminance(Lw)
1,3 0,745 979,8657718
1,5 0,615 1186,99187
1,7 0,501 1457,085828
2 0,373 1957,104558
2,5 0,228 3201,754386
3 0,139 5251,798561
4 0,0518 14092,66409
5 0,0193 37823,8342
6 0,0072 101388,8889
7 0,0027 270370,3704
8 0,001 7,3E-5
9 0,00037 1,972972973E-6
10 0,000139 5,251798561E-6
11 0,000052 1,403846154E-7
12 0,000019 3,842105263E-7
13 7,2E-06 1,013888889E-8
14 2,7E-06 2,703703704E-8
Table 23 Luminance and corresponding shade
From the above analysis we observe that the level of protection offered by different shades are
different, which leads us to the concept of protection factor[12,13].
3.2.1) Protection Factor:
Filter protection factor is the factor by which a filter attenuates the weighted ocular exposure.
Since the transmittances for different shades are different, this implies that they also have
different extends of protection against harmful radiations, hence different protection factors.
The extent to which a filter can protect the eyes also depends on the strength of the incident
spectrum.
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Note: For the wavelength range between 380nm to 780nm, studies was made on the spectral
luminance which is not harmful to the eyes, so instead of talking about protection factor in this
range we shall talk about the comfort factor( formula is the same).
Hence the protection factor should be a function of both the incident spectrum and the
transmittance of the shade as well as the comfort factor. The protection factor is defined
according to [12, 13].
By:
780nm 780nm
PFn= [∑ L(λ).V(λ). ∆λ / ∑ L(λ).V(λ).ζn(λ).∆λ] (12)
380nm 380nm
Where PFn = protection factor for shade n
L(λ) = spectral radiance from the source
ζn(λ) = spectral transmittance for shade n
Note: In the wavelength range 380nm t0 780nm, PFn = CFn
From the protection factor PFn we can obtain the figure of merit [12] by:
PFn.Tn = Ω (13)
Where Tn = luminous transmittance for shade n
Ω = constant
To understand clearly the concept of protection factor we shall first of all seek to meaning of
protection factor: If PFn is the protection factor for a particular source and at a state n of the
filter, then the filter will allow 1/PFn of the incident spectrum to pass through it. We shall
consider a spectrum of Irradiance Eλ incident on shade n = 3 ( this sample is taken from the
article)
As an example, let us consider an arbitrary spectrum of constant spectral irradiance Eλ=107
Wm-3 to obtain the corresponding spectral radiance we use the linear relationship:
Lλ = 4.Eλ / π α2
(W sr-1
m-2
m-1
) (14)
Where α is the angular subtends at the eye. For point sources α ≤ 1,7 mrad. In this case we
consider α = 0,03rad, which is typical of welding arcs.
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Note that it is the angular subtense of 0.03mrad that is used in determining the protection of
the different shades of the filter and shade number.
Substituting the value for Eλ into (14) we obtain Lλ = 1,4154281670E+10 W sr-1 m-2 m-1
Table 24 (see annex) shows the calculation using the distribution of the photopic response of
the eyes:
From which we obtain the CF according to (12) to be CF3= 8,565943295
We now know the comfort factor and the luminous transmittance for the light state(shade 3)
Hence we can obtain the figure of merit Ω from (13).
CF3 = 8,565943295
T3 = 0,113224465
Hence CF3.T3 = Ω = 9,7E-1
Intuitively, if we know the luminous transmittance for all other shades (Table 3) we can use
(13) to obtain their corresponding comfort factors against the light source. As an example, let
us consider the dark state (shade 13) with T13 = 4,79E-06
The corresponding comfort factor is:
CF13 = Ω / T13 = 9,7E-1 / 4,79E-06 = 202505,2
Hence for this particular light source we have obtained the figure of merit and the comfort
factors of light state (shade 3) and the dark state (shade 13).
Up to this point we have studied the characteristics of the filter in the wavelength range from
380nm to 780nm to understand the following:
- Luminous transmittance
- Shade number
- Extent of protection
- Protection factor
- Figure of merit
We shall now focus our attention to the Blue light region (300nm to 700nm) and in the Visible
and IRA region (380nm to 1400nm)
3.2.2) Blue Light Region (300nm to 700nm)
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In this region we seek to understand the protection that the filter will offer against blue light
injury on the retina of the eye.
The spectral property that we will use in this region is the effective radiance (blue light) :
which is the calculated radiance spectral weighted by B(λ), expressed in watts per square
metre per steradian [ Wm-2sr-1 ].
Again we shall work with the light state and the dark state (shade 3 and 13 respectively) to
understand the level of protection that the filter can offer against this type of injury.
a) Case 1 (Shade 3):
Shade 3 has a T = 0,139 and can comfortably reduce an incident spectral luminance of Lv =
5251,798561 cdm-2. The relationship between the luminance and the spectral radiance is given
[7] by :
780nm
Lv = 683.∑V(λ).L(λ).∆λ
(15)
380nm
If we assume that the source emits at a constant (intensity) hence constant spectral radiance
L(λ), then (15)can be rearranged to give:
780nm
L(λ) = Lv / (683 x ∑V(λ).∆λ ) (16)
380nm
From which we have the L(λ) = 7.1959887E+7 Wm-3sr-1 and correspondingly using (14) we
have
Eλ = 50839,66048Wm-3
This implies that a source with spectral irradiance Eλ = 50839,66048 Wm-3 will be prevented
from damaging the eye by shade 3. The obtained value for L(λ) is now put into the following
equation (17) to obtain the incident effective radiance (LB)[10,12]:
700nm
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LB = ∑L(λ).B(λ).∆λ (17)
300nm
LB = 4,936574026 Wm-2sr-1 (calculated from table 6.5 (see annex))
An interpretation of this result is as follows: Shade 3 can be used to protect the eyes if the
incident spectrum has an incident effective radiance of LB = 4,936574026 Wm-2sr-1
To know the amount of blue light which is transmitted through the filter, we need to know the
blue light transmittance TB [14]which is given by
700nm 700nm
TB = ∑ ζ(λ).B(λ).∆λ / ∑ B(λ).∆λ (18)
300nm 300nm
To be more specific the blue light transmittance for shade 3 is given by the formula
700nm 700nm
TB3 = ∑ ζ3(λ).B(λ).∆λ / ∑ B(λ).∆λ (19)
300nm 300nm
Where the calculated TB3 = 0,008345
Table 6.6 (see annex) shows the calculation of TB3
With the calculated TB3 = 0,008345 the transmitted LB in our example will be
LBT= TB3.LB = 0,008345x4,936574026 = 0,041196 Wm-2sr-1
Here we have used the formulation that:
ζ = ξ ζ / ξ i (20)
Where ζ = Transmittance
ξ i = Incident quantity
ξ ζ = Transmitted quantity
If we compare this with the maximum LB MPE according to the directive 2006, we will see
that this value is far lower than what can damage the eyes.
To obtain the blue light protection factor PFBLPH(see table below), corresponding to this
spectral radiance of source and transmittance of filter we use the following formular:
700nm 700nm
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PFBLPH= ∑L(λ).B(λ).∆λ / ∑L(λ).B(λ).ζ(λ).∆λ
(21)
300nm 300nm
The calculation of PFBLPH = 119.8385377 using the same L(λ) calculated from the assumed Eλ
above, is shown on Table 6.7 (see annex):
We have now obtained the blue light protection factor and the blue light transmittances,
We will now use them to calculate the Blue light figure of merit which is given by the
formular:
PFn(PLPH). T = Φ (22)
Where Φ = constant
In this case PFn(PLPH). T = 119,8385377x0,008345 = 16,65756 = Φ
b) Case 2 (Shade 13)
A similar analysis made for the dark state (shade 13) will be:
Shade 13 has a T = 7,2E-06 and can comfortably reduce a maximum incident spectral
luminance of Lv = 1,013888889E+8 cdm-2.
Assuming that the source emits at a constant (intensity) hence constant spectral radiance L(λ) and using (15) we obtain the corresponding L(λ) to be
L(λ) = 1,38923E+12 Wm-3sr-1 with a corresponding E(λ) = 9,814878898E+08 Wm-3.
This implies that a source with spectral irradiance Eλ = 9,814878898E+08 Wm-3 will be
prevented from damaging the eye by shade 13.
The incident LB = 9,54E+4 Wm-2sr-1. This calculation is shown on Table 6.8 (see annex):
If we perform a similar calculation as for shade 3 we will obtain a corresponding blue light
transmittance (TB13) for shade 13.
TB13 = 1,16934E-06
Hence the transmitted LB will be LBT = LBxTB13=9,54E+4x1,16934E-06=0,111442 Wm-2sr-1
We now know the luminous transmittance and the figure of merit for this shade( as it is
constant for all shades) hence we can deduce the blue light protection factor for the shade
according to (22) to have
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PF13(BLPH) = Φ / T = 2313550
In the same light, if the T for any shade is known, the PFn(BLPH) can be deduced.
So far we have been analysing the filter characteristics for α = 0,03rad which is typical of
welding arcs.
Note that more restriction is observed of if α = 1,7mrad
We will now turn our attention to the analysis of the visible light and IRA region (380nm to
1400nm).
3.2.3) Visible Light and IRA (380nm t0 1400nm)
Here we shall do a similar analysis as with the previous section with α = 0,03 rad.
In this region we seek to understand the protection that the filter will offer against visible light
and IRA injury on the retina of the eye (retinal burn).
The spectral property that we will use in this region is the effective radiance (thermal injury) :
which is the calculated radiance spectral weighted by R(λ), expressed in watts per square
metre per steradian [ Wm-2sr-1 ].
Again we shall work with the light state and the dark state (shade 3 and 13 respectively) to
understand the level of protection that the filter can offer against this type of injury.
a) Case 1 (Shade 3):
Shade 3 has a T = 0,139 and can comfortably reduce a incident spectral luminance of Lv =
5251,798561 cdm-2.
If we assume that the source emits at a constant (intensity) hence constant spectral radiance
L(λ) then from (16) L(λ) = 7.1959887E+7 Wm-3sr-1 and correspondingly using (14) we have
Eλ = 50839,66048Wm-3
This implies that a source with maximum spectral irradiance Eλ = 50839,66048 Wm-3 will be
prevented from damaging the eye by shade 3.
The obtained value for L(λ) is now put into the following equation (23) to obtain the incident
effective radiance (LR):
1400nm
LR = ∑L(λ).R(λ).∆λ (23)
380nm
LR = 75,96 Wm-2sr-1 ( calculated from Table 29 ( see annex))
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An interpretation of this result is as follows: Shade 3 can be used to protect the eyes if the
incident spectrum has an incident effective radiance of LR = 75,96 Wm-2sr-1
To know the amount of Visible and IRA radiation which is transmitted through the filter, we
need to know the visible and IRA transmittance TV-IRA [14] which is given by
1400nm 1400nm
Tn(V-IRA) = ∑ ζn(λ).R(λ).∆λ / ∑ R(λ).∆λ (24)
380nm 380nm
To be more specific the visible and IRA transmittance for shade 3 is given by the formula
1400nm 1400nm
T3(V-IRA) = ∑ ζ3(λ).R(λ).∆λ / ∑ R(λ).∆λ (25)
380nm 380nm
Where the calculated T3(V-IRA) = 0,027859815
Table 6.10 (see annex) shows the calculation of T3(V-IRA)
With the calculated TV-IRA = 0,027859815 the transmitted LR in our example will be
LRT= T3(V-IRA).LR = 0,027859815 x75,96 = 2,116231Wm-2sr-1
If we compare this with the maximum LR MPE according to the directive 2006, we will see
that this value is far lower than what can damage the eyes.
To obtain the retinal thermal hazard protection factor PFRTH (see table below), corresponding
to this spectral radiance of source and transmittance of filter we use the following formula [12,
13]:
1400nm 1400nm
PFRTH= ∑L(λ).R(λ).∆λ / ∑L(λ).R(λ).ζ(λ).∆λ (26)
380nm 380nm
The calculated PFRTH = 35,89399341 using the same L(λ) calculated from the assumed Eλ
above, we have Table 6.11 (see annex):
We have now obtained the retinal thermal hazard protection factor and the Visible and IRA
transmittance,
We will now calculate the visible and IRA figure of merit which is given by the formular:
PFn(RTH). T = Φ (27)
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Where Φ = constant
In this case PFn(RTH). T = 35, 89399341 x 0,139 = 4, 989265= Φ
b) Case 2 (Shade 13)
A similar analysis made for the dark state (shade 13) will be:
Shade 13 has a T = 7,2E-06 and can comfortably reduce an incident spectral luminance of
Lv = 1,013888889E+8 cdm-2.
Assuming that the source emits at a constant (intensity) hence constant spectral radiance L(λ) and using (15) we obtain the corresponding L(λ) to be
L(λ) = 1,38923E+12 Wm-3sr-1 with a corresponding E(λ) = 9,814878898E+08 Wm-3.
This implies that a source with spectral irradiance Eλ = 9,814878898E+08 Wm-3 will be
prevented from damaging the eye by shade 13.
The incident LR = 1,47E+06 Wm-2sr-1. This calculation is shown on Table 6.12 (see annex):
If we perform a similar calculation as for shade 3 we will obtain a corresponding visible and
IRA transmittance (TV-IRA) for shade 13.
T13(V-IRA) = 2,88143E-06
Hence the transmitted LR will be
LRT = LRxT13(V-IRA)= 1,47E+06 +4x2,88143E-06=4,235705827 Wm-2sr-1
We now know the visible and IRA transmittance for this shade and using the figure of merit
for obtained from shade 3 we can deduce the blue light protection factor for this shade
according to (14) to have
PF13(V-IRA) = Φ / T = 692953,5
In the same light, if the T for any state is known, the PFn(RTH) can be deduced.
All above analysis have been done for the filter characteristics for α = 0,03rad which is typical
of welding arcs.
Below is Table 33 showing the different shades, luminous transmittance, corresponding
spectral radiance that could be reduced to a comfortable level, and the corresponding incident
blue light and visible-IRA radiations.
Shade T Incident Luminance L(λ) LB LR
1,3 0,745 979,8657718 13426072,96 0,921052 14,1724
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1,5 0,615 1186,99187 16264104,64 1,115746 17,16819
1,7 0,501 1457,085828 19964918,87 1,369628 21,07473
2 0,373 1957,104558 26816151,09 1,839635 28,30681
2,5 0,228 3201,754386 43870282,26 3,009578 46,30895
3 0,139 5251,798561 71959887,44 4,936574 75,96
4 0,0518 14092,66409 193096995,3 13,24679 203,8309
5 0,0193 37823,8342 518260329,3 35,55356 547,0694
6 0,0072 101388,8889 1389225605 95,3033 1466,45
7 0,0027 270370,3704 3704601613 254,1421 3910,533
8 0,001 730000 10002424355 686,1838 10558,44
9 0,00037 1972972,973 27033579337 1854,551 28536,32
10 0,000139 5251798,561 71959887444 4936,574 75960
11 0,000052 14038461,54 1,92354E+11 13195,84 203046,9
12 0,000019 38421052,63 5,26443E+11 36114,94 555707,4
13 7,2E-06 101388888,9 1,38923E+12 95303,3 1466450
14 2,7E-06 270370370,4 3,7046E+12 254142,1 3910533
Table 33 Shade transmittance and incident spectral properties
Analysis will then be done on this table using the MPE’s specified by the 2006 Directive to
show the shades which need more protection against the blue light and visible-IRA incident
radiations within an exposure time of 0,5s, which is the main aim of this project.
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4 Result : Determination of Damage from Intense Light Exposure
In determining the hazard which may be caused to the eyes from exposure to intense light,
instead of using mathematical analysis we shall employ a graphical technique whereby the
incident spectra will be plotted on the same axes as the MPE limits stipulated in the adopted
2006 directive (see section 3.1 of chapter 3). At any given exposure time the MPE limit value
will be divided by the incident spectrum value to give what we shall called the protection ratio
(PR). If the result is greater than or equal to one (≥ 1) then no further protection is needed
otherwise further protection will be needed. This explanation is shown mathematically below:
≥ 1 no further protection needed
PR = MPE Limitt /Incident Spectrumt = <1 further protection needed (28)
In this investigation two types of sources will be considered: point source (α = 0,0017rad) and
welding arc (α = 0,03rad).
Depending on the particular spectral property for investigation, t will be considered for
exposure duration of 0,5s and long exposure times. In the cases of blue light and Visible &
IRA, long exposure times are when t >10000s and t> 10s respectively because after these
times the MPE limit values remain constant.
To understand the reasoning behind this techniques, let us consider the example below:
Consider the incident spectrum of a CIA-E source corresponding to that which can be
protected by shade 3.This is shown graphically below (fig 4.1):
E(λ) / λ(nm)
0
20000
40000
60000
80000
100000
120000
140000
160000
0 200 400 600 800 1000 1200 1400 1600
wavelength λ(nm)
E(λ
)[W
m^
-2 s
r^-1
]
E(λ) / λ(nm)
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Fig 4.1 E(λ)/ λ(nm)
From this spectrum, the blue light and the Visible & IRA radiations are calculated using
equations 17 and 23 respectively (Lλ is obtained using equation 14). These are then plotted for
different angular subtense (α = 0,03rad and α = 0,0017rad). The ratio of the MPE limit and the
incident spectrum are then obtained according to equation 28.
The graph for α = 0,03rad is shown below (it has been zoomed for clarity so only the part
necessary for investigation is shown)
LB/T Graph
0
200000
400000
600000
800000
1000000
1200000
1400000
1600000
1800000
2000000
0 2 4 6 8 10
Exposure time (T/s)
LB
[Wm
^-2
sr^
-1]
MPE Limit LB
(α≥11mrad)
Source Blue l ight (LBi)
Fig 4.2 LB/T Graph (zoomed)
LB/T Graph
1
100
10000
1000000
100000000
10000000000
0 5000 10000 15000
Exposure time(t/s)
LB
[W
m^
-2 s
r^-1
]
MPE Limit LB
(α≥11mrad)
Source Blue
light (LBi)
Fig 4.2 LB/T Graph (entire graph shown on a logarithmic scale)
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The red line ( ILBiI ≈1.6 )shows the source incident LB and the blue line shows the MPE limit
value.
For t = 0,5s equation 28 gives:
PR = MPE Limitt=0.5 /Incident Spectrumt=0.5 = 1250590.654 >> 1
Hence no protection is needed.
For very long exposure time, we consider fig 4.3 below. For this example t > 10000s,
LB/T Graph
0
500
1000
1500
2000
0 2000 4000 6000 8000 10000
Exposure time(t/s)
LB
[W
m^
-2 s
r^-1
]
MPE Limit LB
(α≥11mrad)
Source Blue
light (LBi)
Fig 4.3 LB/T Graph (zoomed)
LB/T Graph
1
100
10000
1000000
100000000
10000000000
0 5000 10000 15000
Exposure time(t/s)
LB
[W
m^
-2 s
r^-1
]
MPE Limit LB
(α≥11mrad)
Source Blue
light (LBi)
Fig 4.3 LB/T Graph (entire graph shown on a logarithmic scale)
Caluclations show that:
PR = MPE Limit t>10000 /Incident Spectrum t>10000 = 62.5295327 > 1
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Hence no protection is needed.
Note: For the long exposure time, we have considered any value after t = 10000s since from
this point onwards the MPE limit is a constant value
This method was later generalised to the different shades and different assumed spectra using
the different values of the angular subtense (α = 0,03rad and α = 0,0017rad).
Also in following investigations light sources with three different spectral distributions have
been considered. To give a feeling on what is meant by different spectral irradiances the figure
below (fig 4.4) is used to illustrate 3 different spectra all with light intensity for which shade
13 could be used to protect the eyes. Graph 1 (Blue line) is a rough approximation of sub-
figure 6 in figure 3.1 in chapter 3 (whose spectral distribution will be used in the proceding
investigation). Graph 2 (purple line) is the standard CIE-A source and Graph 3 is an arbitrary
constant curve which will also be used in the second investigation. Observe that all three
graphs show different spectral distribution but are all shielded from damaging the eyes by
shade 13.
Spectral Irradiance/Wavelength
0
500000000
1000000000
1500000000
2000000000
2500000000
3000000000
3500000000
4000000000
300 500 700 900 1100 1300 1500
Wavelngth [nm]
Sp
ec
tra
l Ir
rad
ian
ce
[Wm
^-3
]
Graph 1
Graph 2 (CIE-A)
Graph 3
Fig 4.4 Different Spectra which may correspond to different welding arcs.
In the investigation, same spectral irradiance was used and it was assumed that it was
produced initially from a welding arc and later from a point source.
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The following results were obtained:
a) CIE-A Source without Filter in Place
The first investigation was made of the CIE-A standard source corresponding to the different
shades
E(λ)
Shade
α = 0,03rad
Blue Light Protection Ratio
(300nm – 700nm)
Required Visible & IRA
Protection Ratio (380nm -
1400nm)
t = 0,5s t>10000s t = 0,5s t>10s
CIE-A 1,3 6702806,023 335,1403011 152385,0908 71833,85264
CIE-A 1,5 5533188,865 276,6594432 125794,4038 59299,08641
CIE-A 1,7 4507524,587 225,3762294 102476,4168 48307,06063
CIE-A 2 3355901,539 167,795077 76294,81727 35965,13696
CIE-A 2,5 2051328,555 102,5664277 46635,9741 21984,05155
CIE-A 3 1250590,654 62,5295327 28431,5807 13402,55774
CIE-A 4 466047,4523 23,30237262 10595,36604 4994,622237
CIE-A 5 173643,1627 8,682158137 3947,694299 1860,930679
CIE-A 6 64778,79646 3,238939823 1472,714971 694,2332067
CIE-A 7 24292,04867 1,214602434 552,2681143 260,3374525
CIE-A 8 8997,055064 0,449852753 204,543746 96,42127871
CIE-A 9 3328,910374 0,166445519 75,68118603 35,67587312
CIE-A 10 1250,590654 0,062529533 28,4315807 13,40255774
CIE-A 11 467,8468633 0,023392343 10,63627479 5,013906493
CIE-A 12 170,9440462 0,008547202 3,886331175 1,832004295
CIE-A 13 64,77879646 0,00323894 1,472714971 0,694233207
CIE-A 14 24,29204867 0,001214602 0,552268114 0,260337453
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Fig. 4.5 PR when using the standard CIE-A source without filter in place for α = 0,03rad
E(λ)
Shade
α = 0,0017rad
Blue Light Protection Ratio
(300nm – 700nm)
Required Visible & IRA
Protection Ratio (380nm -1400nm)
t = 0,5s t>10000s t = 0,5s t>10s
CIE-A 1,3 948734,0443 47,43670222 8635,155145 4070,584983
CIE-A 1,5 783183,1372 39,15915686 7128,349549 3360,281563
CIE-A 1,7 638007,7264 31,90038632 5806,99695 2737,400103
CIE-A 2 475003,7564 23,75018782 4323,372979 2038,024428
CIE-A 2,5 290350,8216 14,51754108 2642,705199 1245,762921
CIE-A 3 177012,1237 8,850606185 1611,122906 759,478272
CIE-A 4 65965,66912 3,298283456 600,4040759 283,0285934
CIE-A 5 24577,94236 1,228897118 223,7026769 105,4527385
CIE-A 6 9168,973314 0,458448666 83,45384838 39,33988171
CIE-A 7 3438,364993 0,17191825 31,29519314 14,75245564
CIE-A 8 1273,468516 0,063673426 11,59081228 5,46387246
CIE-A 9 471,1833509 0,023559168 4,288600542 2,02163281
CIE-A 10 177,0121237 0,008850606 1,611122906 0,759478272
CIE-A 11 66,22036282 0,003311018 0,602722238 0,284121368
CIE-A 12 24,1959018 0,001209795 0,220225433 0,103813577
CIE-A 13 9,168973314 0,000458449 0,083453848 0,039339882
CIE-A 14 3,438364993 0,000171918 0,031295193 0,014752456
Fig 4.6 PR when using the standard CIE-A source without filter in place for α = 0,0017rad
Note that for all PR < 1, protection against damage is needed. Observation above, we will
need some protection for certain shades.
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b) Light Source with Constant Spectral Distribution without Filter in Place:
The sources were chosen such that it has the maximum possible incident spectrum that could
be protected by the corresponding shade.
E(λ)
Shade
α = 0,03rad
Blue Light Protection Ratio
(300nm – 700nm)
Required Visible & IRA
Protection Ratio (380nm -1400nm)
t = 0,5s t>10000s t = 0,5s t>10s
103,98 1,3 2156785,64 107,839282 138761,119 65411,55515
104,064 1,5 1777489,252 88,87446261 114358,327 53908,15576
104,065 1,7 1773401,14 88,67005702 114095,3102 53784,17045
104,29 2 1056347,925 52,81739623 67962,25702 32037,19426
104,493 2,5 661922,2555 33,09611277 42586,09252 20074,95011
104,71 3 401612,2797 20,08061399 25838,52947 12180,20154
105,17 4 139253,777 6,962688849 8959,170328 4223,324721
105,6 5 51737,68393 2,586884197 3328,6474 1569,113918
106 6 20597,14296 1,029857148 1325,158398 624,6755021
106,46 7 7141,788479 0,357089424 459,4812494 216,5980162
106,85 8 2909,423775 0,145471189 187,183599 88,23775999
107,3 9 1032,30251 0,051615126 66,41524718 31,30793868
107,8 10 326,4427166 0,016322136 21,00234524 9,900439508
108,16 11 142,4974141 0,007124871 9,167856213 4,321698591
108,55 12 58,05063616 0,002902532 3,734803811 1,760574773
109 13 20,59714296 0,001029857 1,325158398 0,624675502
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109,5 14 6,513388505 0,000325669 0,41905188 0,197539739
Fig 4.7 PR when using a constant spectral distribution source for α = 0,03rad
E(λ)
Shade
α = 0,0017rad
Blue Light Protection Ratio
(300nm – 700nm)
Visible & IRA Protection Ratio
(380nm -1400nm)
t = 0,5s t>10000s t = 0,5s t>10s
103,98 1,3 305277,5146 15,26387573 7863,130074 3706,654792
104,064 1,5 251590,8354 12,57954177 6480,305197 3054,795493
104,065 1,7 251012,1925 12,55060963 6465,400909 3047,769659
104,29 2 149518,4607 7,475923033 3851,194564 1815,441008
104,493 2,5 93690,34047 4,684517024 2413,21191 1137,580506
104,71 3 56845,3333 2,842266665 1464,183337 690,2114208
105,17 4 19710,37183 0,985518592 507,6863186 239,3217342
105,6 5 7323,097514 0,366154876 188,6233527 88,91645534
106 6 2915,377631 0,145768882 75,09230924 35,39827845
106,46 7 1010,868858 0,050543443 26,0372708 12,27388758
106,85 8 411,808036 0,020590402 10,60707061 5,000139733
107,3 9 146,115005 0,00730575 3,763530673 1,774116525
107,8 10 46,20562161 0,002310281 1,190132897 0,561024905
108,16 11 20,16948537 0,001008474 0,519511852 0,244896254
108,55 12 8,216650553 0,000410833 0,211638883 0,099765904
109 13 2,915377631 0,000145769 0,075092309 0,035398278
109,5 14 0,921923355 4,60962E-05 0,023746273 0,011193919
Fig 4.8 PR when using a constant spectral distribution source for α = 0,0017rad
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Observe that for this assumed incident spectra (which correspond to the different shades) PR <
1, hence we now seek to see if the filter can protect the eyes from damage using the
transmittance of the light state (shade 3).
c) Light Source with Constant Spectral Distribution with Filter in Place
Since this investigation concerns switching from light to dark state, we will assume that our
filter is in the light state and we shall use the transmittance of the light state to draw our
conclusions below. In the presence of the filter we have the following conclusions on the
table below:
E(λ)
Shade
α = 0,03rad
Blue Light Protection Ratio
(300nm – 700nm)
Required Visible & IRA
Protection Ratio (380nm -1400nm)
t = 0,5s t>10000s t = 0,5s t>10s
106,46 7 Eye is
protected*
106,85 8 Eye is
protected*
107,3 9 Eye is
protected*
107,8 10 Eye is
protected*
108,16 11 Eye is
protected*
108,55 12 Eye is
protected*
109 13
Eye is
protected*
Eye is
protected*
109,5 14 Eye is
protected*
Eye is
protected*
Eye is
protected*
* = light state transmittance protects the eyes
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Fig 4.9 Conclusion drawn with filter in the light state for α = 0,03rad
E(λ)
Shade
α = 0,0017rad
Blue Light Protection Ratio
(300nm – 700nm)
Visible & IRA Protection Ratio
(380nm -1400nm)
t = 0,5s t>10000s t = 0,5s t>10s
105,17 4 Eye is
protected*
105,6 5 Eye is
protected*
106 6 Eye is
protected*
106,46 7 Eye is
protected*
106,85 8 Eye is
protected*
107,3 9 Eye is
protected*
107,8 10 Further
protection
needed from
t≈3260s
Eye is
protected*
108,16 11 Further
protection
needed from
t≈1425s
Eye is
protected*
Eye is
protected*
108,55 12 Further
protection
needed from
Eye is
protected*
Eye is
protected*
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t≈575s
109 13
Further
protection
needed from
t≈200s
Eye is
protected*
Eye is
protected*
109,5 14 Eye is
protected*
Further
protection
needed from
t≈55s
Eye is
protected*
Further
protection
needed from
t≈2s
* = light state transmittance protects the eyes
Fig 4.10 Conclusion drawn with filter in the light state for α = 0,0017rad
Observe that, for exposure time of 0.5s (which is the goal of this project) the light state
transmittance offer enough protection. In the same way, different sources with different
properties could be investigated to see if there is no risk of damage in case of a delay in
switching from the light state to the dark state. To this effect we will look at the example of
the welding spectrum below, which is a rough approximation of sub-figure 6 of figure 2.13 in
chapter 2. This spectrum was chosen because of its very intense blue light radiation. After the
approximated distribution of the spectrum was obtained, it was then multiplied by arbitrary
constant factors in order for it to correspond to the intensity of light that could be protected by
the different shades of the welding filter. It was then investigated on two different angular
subtenses (α = 0,03rad and α = 0,0017rad).
The results of this investigation are presented on the tables 4.11 and 4.12 below.
d) Approximation of Real Welding Spectra without Filter In Place
E(λ)
Shade
α = 0,03rad
Blue Light Protection Ratio
(300nm – 700nm)
Visible & IRA Protection Ratio
(380nm -1400nm)
t = 0,5s t>10000s t = 0,5s t>10s
3 252939,6151 12,64698075 19103,29973 9005,235424
4 79043,62971 3,952181485 5969,781166 2814,13607
5 35130,50209 1,756525105 2653,236074 1250,727142
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6 12646,98075 0,632349038 955,1649866 450,2617712
7 4516,778841 0,225838942 341,1303523 160,8077754
8 1580,872594 0,07904363 119,3956233 56,2827214
9 632,3490377 0,031617452 47,75824933 22,51308856
10 252,9396151 0,012646981 19,10329973 9,005235424
11 63,23490377 0,003161745 4,775824933 2,251308856
12 31,61745188 0,001580873 2,387912466 1,125654428
13 12,64698075 0,000632349 0,955164987 0,450261771
14 4,864223367 0,000243211 0,367371149 0,173177604
Fig 4.11 PR for α = 0,0017rad without filter in place
E(λ)
Shade
α = 0,0017rad
Blue Light Protection Ratio
(300nm – 700nm)
Visible & IRA Protection Ratio
(380nm -1400nm)
t = 0,5s t>10000s t = 0,5s t>10s
3 35801,78557 1,790089279 1082,520318 510,2966741
4 11188,05799 0,5594029 338,2875994 159,4677106
5 4972,470218 0,248623511 150,3500442 70,87453806
6 1790,089279 0,089504464 54,12601591 25,5148337
7 639,3175995 0,03196588 19,33071997 9,112440608
8 223,7611598 0,011188058 6,765751988 3,189354213
9 89,50446393 0,004475223 2,706300795 1,275741685
10 35,80178557 0,001790089 1,082520318 0,510296674
11 8,950446393 0,000447522 0,27063008 0,127574169
12 4,475223197 0,000223761 0,13531504 0,063787084
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13 1,790089279 8,95045E-05 0,054126016 0,025514834
14 0,688495876 3,44248E-05 0,020817698 0,009813398
Figure 4.12 PR for α = 0,03rad without filter in place
Observe that certain PRs are less than one which means that, these shades needed further
protection.
With the filter now in place and set to the light state (shade 3) the following conclusion were
drawn for the condition PR < 1: These conclusions are shown on figure 4.13 and 4.14
E) Approximation of Real Welding Spectra with Filter in Place.
E(λ)
Shade
α = 0,03rad
Blue Light Protection Ratio
(300nm – 700nm)
Visible & IRA Protection Ratio
(380nm -1400nm)
t = 0,5s t>10000s t = 0,5s t>10s
6
Eye is
protected*
7
Eye is
protected*
8
Eye is
protected*
9
Eye is
protected*
10
Eye is
protected*
11
Further
protection
needed from
t≈4500s
12
Further
protection
needed from
t≈2370s
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13
Further
protection
needed from
t≈1050s
Eye is
protected*
Eye is
protected*
14
Further
protection
needed from
t≈345s
Eye is
protected*
Eye is
protected*
* = light state transmittance protects the eyes: Fig 4.13 Conclusion drawn with filter in the light
state for α = 0,03rad
E(λ)
Shade
α = 0,0017rad
Blue Light Protection Ratio
(300nm – 700nm)
Visible & IRA Protection Ratio
(380nm -1400nm)
t = 0,5s t>10000s t = 0,5s t>10s
4
Eye is
protected*
5
Eye is
protected*
6
Eye is
protected*
7
Eye is
protected*
8
Eye is
protected*
9
Further
protection
needed from
t≈6200s
10
Further
protection
needed from
t≈2530s
Eye is
protected*
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11
Further
protection
needed from
t≈630s
Eye is
protected*
Eye is
protected*
12
Further
protection
needed from
t≈320s
Eye is
protected*
Eye is
protected*
13
Further
protection
needed from
t≈130s
Eye is
protected*
Eye is
protected*
14 Further
protection
needed from
t≈45s
Further
protection
needed from
t≈1050s
Further
protection
needed from
t≈1.2s
Further
protection
needed from
t≈1.2s
* = light state transmittance protects the eyes
Figure 4.14 Conclusion drawn with filter in the light state for α = 0,0017rad
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5 Discussion The work was carried out in the Research and Development (R&D) Department of 3M
Svenska AB branch in Gagnef, Sweden. So many challenges were faced during the evolution
of the project, which led to a deeper research and understand of the problem area to bring forth
solutions to these mile stones. In order for simulation to be successfully done, an excel
worksheet was developed from scratch which served as the main simulation tool (see
accompanying CD on the cover of this project report). Critical thinking was employed, with
best and worse case scenarios investigated.
The fundamental aspects of LC-technology was studied at depth, the optics of the eyes and the
sources and processes producing electromagnetic radiations was also looked into.
A combination of all these made it possible to simulate the product properties according to
the most recent international standards and to draw logical conclusions, thus attaining the
objective of the project.
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6 Conclusion / Recommendations
a) Conclusion
The objective of this project was to determine the thermal and blue light photochemical
hazard protection needed by automatic welding filters within 0.5 seconds of switching failure.
Before simulating to get our results an introduction was done to understand the technology
behind the filter and how the filter works. Also, since the filter filters waves coming from
welding arcs, an introduction was also made to understand the kind of intense light radiation
from such process. Yet to understand the level of protection the eye needed, we also needed to
have a limit beyond which damage may be caused to the eyes. To this effect, different MPE
standards were compared and that with least restrictive limits was used (2006 Directive)
In order to get a mathematical formulation to quantify our results the concept of the
Protection Ratio was introduced as defined by equation 28 of chapter 4. Finally, simulations
were made on different spectra for the unprotected eye and when using the filter in the light
state (shade 3).
The conclusion was that in the case of 0.5 s of switching failure, blue light attenuation will be
needed for products with the darkest shade 11 or higher. The transmittance requirements can
be taken from the tables of chapter 4 as the protection ratios below 1 (PR<1). In case of a
switching failure the requirement for the darkest shade of a product shall apply also to the
lightest state. The light state of the current product fulfils the requirement and the eye is
protected. Even in the case were the filter failed to switch, the eye would not be damaged
since the light state transmittance could still attenuate the incident light to below the harmful
level.
Today there are products that are shade 3 in the light state and shade 13 in the darkest state.
Since we have the interference filter that block a lot of blue light the products are safe. If it
would be possible to make a product with shade 1.2 in the light state and not necessarily use
an interference filter, then we would not be sure that such a product would be safe without
having a requirement for blue light transmittance. The most important conclusion of this work
is the transmittance requirements needed when the darkest state is above shade 11. For
example consider figure 4.12. If the darkest shade is 13, the VIS/IR-transmittance in the
lightest state (that might theoretically be nearly clear) must not be higher than 0.054 (5.4%) in
case of a switching failure. You then have a light source relating to the shade 13, but the
welding filter is in the light state and you need to be protected until you close your eyes or turn
your head after about 0.5 s. The importance of the values below 1.0 is further pointed out by
the red colour numbers of the boxes. For example figure 4.12.Hence a requirement would be
needed for the light state when the darkest state is above shade 11.
However one can confidently conclude that the eye stands little or no chance of damage within
0.5 s of switching failure with products today.
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b) Recommendations:
- The protection ratio can be expressed in a standard as the weighted transmittance (TB and TV-
IRA) and the requirement can be taken from the values of chapter 4 where the protection factor
is below 1.
- The emission spectrum from the welding arc in different welding situations varies depending
on the welding method, material, shielding gas and current used. Therefore it would be good
to analyze different welding spectra and do the analysis for each spectrum.
- The blink reflex is often mentioned as 0.25 s hence 0.5 s then gives some error margin.
However, if the welding filter fails to switch several times, a longer time perhaps should be
considered for further investigation.
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7 References [1] P. Jägemalm, On the Optics and Surface Physics of Liquid Crystal, Göteborg, Sweden
1999 pp. 85
[2] L. M. Mlinov and V. G. Chigrinov, Electrooptic Effects in Liquid Crystal Materials,
New York, Spring-Verlag New York, Inc., 1994
[3] V. G. Chigrinov, Liquid Crystal Devices : Physics and Applications, Boston, Artech
House Optoelectronics Library, 1999, pp 85-102
[4] B. Bahadur, Liquid Crystal Applications and Uses Vol 2
[5] “Minimum health and Safety requirements regarding the exposure of workers to risk
arising from physical agents (artificial optical radiation) (19th individual Directive within the
meaning of Article 16(1) of Directive 89/391/EEC)”, Official Journal of the European Union,
Directive 2006/257ec, pp. L114/38 – Lii1/52, April 2006
[6] Palmebalds, Sandvik Welding Handbook, Goterborg, Sweden AB, 1977
[7] E. Sutter, and A. Schirmacher, “ The Infrared Transmittance of Eye Protection
Filters”, Pysikalisch – Technische Bundesanstalt Braunschweig, 2005
[8] S. Palmer, The Optical Properties of Automatically Darkening Welding Filters on
Liquid Crystal Technology, Uppsala, University of Uppsala, 1998
[9] E. Buhr and E. Sutter, “ Dynamic Filters for Protection Devices”, Physikalisch –
Technische Bundesanstalt, Braunschweig, (West Germany), March 1990
[10] “Compilation of maximum Permissible Exposure to Incoherent Optical Radiation”
IEC tR 60825-9, Geneva, Switzerland, October 1999
[11] “Safety of Laser Products; Part 1 : Equipment Classification and requirement” IEC
60825 – 1, Geneva, Switzerland, March, 2007
[12] D. Mc G Clarkson, “ Determination of eye filter protection factors assocviated with
retinal thermal hazard and blue light photochemical hazard for intense pulse light
source”,Institute of Physics Publishing, UK, January 2006
[13] Eyewear for protection against intense light sources used on humans and animals for
cosmetic and medical application, Part 1, Specification for Products, British Standard, BS
8497 – 1: 2008
[14] Occupational and Educational Personal Eye and Face Protection Devices, American
National Standard, American Society of safety Engineers, ANSI Z87, January 2008 .
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Appendices
Appendix A (Annex) Calculations
λ(nm) V(λ) SCIE-A(λ) ∆λ ζ3 ζ13 D ∏3 ∏13
380 0 9,8 5E-09 2,54E-06 8,55E-09 0 0 0,00E+00
385 0,0001 10,9 5E-09 -2,4E-07 3,39E-09 5,45E-12 -1,28811E-18 1,85E-20
390 0,0001 12,09 5E-09 -5,8E-06 3,79E-09 6,045E-12 -3,48795E-17 2,29E-20
395 0,0002 13,35 5E-09 -2,4E-06 3,86E-08 1,335E-11 -3,15207E-17 5,15E-19
400 0,0004 14,71 5E-09 7,95E-05 2,89E-07 2,942E-11 2,33973E-15 8,49E-18
405 0,0006 16,15 5E-09 0,000195 7,06E-07 4,845E-11 9,43919E-15 3,42E-17
410 0,0012 17,68 5E-09 0,000475 1,11E-06 1,0608E-10 5,03741E-14 1,18E-16
415 0,0022 19,29 5E-09 0,000701 1,23E-06 2,1219E-10 1,48714E-13 2,61E-16
420 0,004 20,99 5E-09 0,000845 1,18E-06 4,198E-10 3,54545E-13 4,94E-16
425 0,0073 22,79 5E-09 0,001049 1,12E-06 8,31835E-10 8,72577E-13 9,29E-16
430 0,0116 24,67 5E-09 0,001217 1,03E-06 1,43086E-09 1,74172E-12 1,47E-15
435 0,0168 26,64 5E-09 0,001427 9,20E-07 2,23776E-09 3,19417E-12 2,06E-15
440 0,023 28,7 5E-09 0,00176 8,58E-07 3,3005E-09 5,80724E-12 2,83E-15
445 0,0298 30,85 5E-09 0,002133 7,67E-07 4,59665E-09 9,80379E-12 3,53E-15
450 0,038 33,09 5E-09 0,002546 6,93E-07 6,2871E-09 1,60095E-11 4,36E-15
455 0,048 35,41 5E-09 0,003273 6,67E-07 8,4984E-09 2,78146E-11 5,67E-15
460 0,06 37,81 5E-09 0,004134 6,73E-07 1,1343E-08 4,68908E-11 7,63E-15
465 0,0739 40,3 5E-09 0,005351 6,87E-07 1,48909E-08 7,96796E-11 1,02E-14
470 0,091 42,87 5E-09 0,007315 7,50E-07 1,95059E-08 1,4269E-10 1,46E-14
475 0,1126 45,52 5E-09 0,009852 8,55E-07 2,56278E-08 2,52475E-10 2,19E-14
480 0,139 48,24 5E-09 0,013387 1,00E-06 3,35268E-08 4,48828E-10 3,36E-14
485 0,1693 51,04 5E-09 0,019245 1,28E-06 4,32054E-08 8,31501E-10 5,52E-14
490 0,208 53,91 5E-09 0,027964 1,72E-06 5,60664E-08 1,56786E-09 9,64E-14
495 0,2586 56,85 5E-09 0,040507 2,63E-06 7,35071E-08 2,97752E-09 1,93E-13
500 0,323 59,86 5E-09 0,05928 3,97E-06 9,66739E-08 5,73087E-09 3,84E-13
505 0,4073 62,93 5E-09 0,087976 6,11E-06 1,28157E-07 1,12747E-08 7,83E-13
510 0,503 66,06 5E-09 0,12158 1,00E-05 1,66141E-07 2,01994E-08 1,66E-12
515 0,6082 69,25 5E-09 0,147754 1,22E-05 2,10589E-07 3,11153E-08 2,58E-12
520 0,71 72,5 5E-09 0,163568 1,31E-05 2,57375E-07 4,20983E-08 3,37E-12
525 0,7932 75,79 5E-09 0,17287 1,24E-05 3,00583E-07 5,19618E-08 3,72E-12
530 0,862 79,13 5E-09 0,170758 1,12E-05 3,4105E-07 5,82369E-08 3,83E-12
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535 0,9149 82,52 5E-09 0,160155 9,35E-06 3,77488E-07 6,04567E-08 3,53E-12
540 0,954 85,95 5E-09 0,149557 7,37E-06 4,09982E-07 6,13154E-08 3,02E-12
545 0,9803 89,41 5E-09 0,14706 6,16E-06 4,38243E-07 6,4448E-08 2,70E-12
550 0,995 92,91 5E-09 0,146509 5,55E-06 4,62227E-07 6,77206E-08 2,57E-12
555 1 96,44 5E-09 0,145312 5,22E-06 4,822E-07 7,00696E-08 2,52E-12
560 0,995 100 5E-09 0,140117 4,85E-06 4,975E-07 6,97082E-08 2,41E-12
565 0,9786 103,58 5E-09 0,136125 4,29E-06 5,06817E-07 6,89903E-08 2,17E-12
570 0,952 107,18 5E-09 0,133278 3,84E-06 5,10177E-07 6,79955E-08 1,96E-12
575 0,9154 110,8 5E-09 0,128646 3,72E-06 5,07132E-07 6,52402E-08 1,88E-12
580 0,87 114,44 5E-09 0,121628 3,53E-06 4,97814E-07 6,05481E-08 1,76E-12
585 0,8163 118,08 5E-09 0,111346 3,29E-06 4,81944E-07 5,36625E-08 1,59E-12
590 0,757 121,73 5E-09 0,102724 2,94E-06 4,60748E-07 4,73297E-08 1,35E-12
595 0,6949 125,39 5E-09 0,097063 2,76E-06 4,35668E-07 4,22872E-08 1,20E-12
600 0,631 129,04 5E-09 0,092695 2,64E-06 4,07121E-07 3,7738E-08 1,08E-12
605 0,5668 132,7 5E-09 0,089898 2,55E-06 3,76072E-07 3,3808E-08 9,58E-13
610 0,503 136,35 5E-09 0,086728 2,71E-06 3,4292E-07 2,97408E-08 9,28E-13
615 0,4412 139,99 5E-09 0,082917 2,70E-06 3,08818E-07 2,56062E-08 8,35E-13
620 0,381 143,62 5E-09 0,078648 2,65E-06 2,73596E-07 2,15177E-08 7,24E-13
625 0,321 147,24 5E-09 0,071321 2,40E-06 2,3632E-07 1,68545E-08 5,68E-13
630 0,265 150,84 5E-09 0,059863 2,09E-06 1,99863E-07 1,19644E-08 4,18E-13
635 0,217 154,42 5E-09 0,046208 1,73E-06 1,67546E-07 7,74193E-09 2,90E-13
640 0,175 157,98 5E-09 0,0329 1,33E-06 1,38233E-07 4,54789E-09 1,84E-13
645 0,1382 161,52 5E-09 0,022313 9,84E-07 1,1161E-07 2,4904E-09 1,10E-13
650 0,107 165,03 5E-09 0,015031 7,03E-07 8,82911E-08 1,32706E-09 6,20E-14
655 0,0816 168,51 5E-09 0,010203 5,03E-07 6,87521E-08 7,01462E-10 3,46E-14
660 0,061 171,96 5E-09 0,006982 3,78E-07 5,24478E-08 3,66205E-10 1,98E-14
665 0,0446 175,38 5E-09 0,004926 2,88E-07 3,91097E-08 1,92653E-10 1,12E-14
670 0,032 178,77 5E-09 0,003475 2,21E-07 2,86032E-08 9,93947E-11 6,32E-15
675 0,0232 182,12 5E-09 0,002434 1,74E-07 2,11259E-08 5,14161E-11 3,67E-15
680 0,017 185,43 5E-09 0,00183 1,60E-07 1,57616E-08 2,88486E-11 2,53E-15
685 0,0119 188,7 5E-09 0,001356 1,38E-07 1,12277E-08 1,52296E-11 1,55E-15
690 0,0082 191,93 5E-09 0,001043 1,18E-07 7,86913E-09 8,21086E-12 9,26E-16
695 0,0057 195,12 5E-09 0,000804 1,25E-07 5,56092E-09 4,47336E-12 6,93E-16
700 0,0041 198,26 5E-09 0,000622 1,11E-07 4,06433E-09 2,52934E-12 4,49E-16
705 0,0029 201,36 5E-09 0,000463 1,37E-07 2,91972E-09 1,35255E-12 4,00E-16
710 0,0021 204,41 5E-09 0,000377 1,57E-07 2,14631E-09 8,08532E-13 3,37E-16
715 0,0015 207,41 5E-09 0,00031 1,90E-07 1,55558E-09 4,82058E-13 2,95E-16
720 0,001 210,36 5E-09 0,000253 2,53E-07 1,0518E-09 2,6647E-13 2,66E-16
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725 0,0007 213,27 5E-09 0,000206 3,33E-07 7,46445E-10 1,53539E-13 2,49E-16
730 0,0005 216,12 5E-09 0,000183 4,62E-07 5,403E-10 9,87457E-14 2,50E-16
735 0,0004 218,92 5E-09 0,000158 6,52E-07 4,3784E-10 6,90948E-14 2,86E-16
740 0,0002 221,67 5E-09 0,000127 8,25E-07 2,2167E-10 2,80602E-14 1,83E-16
745 0,0002 224,36 5E-09 9,26E-05 1,24E-06 2,2436E-10 2,07804E-14 2,78E-16
750 0,0001 227 5E-09 0,000105 1,74E-06 1,135E-10 1,19456E-14 1,98E-16
755 0,0001 229,59 5E-09 7,69E-05 2,27E-06 1,14795E-10 8,82919E-15 2,60E-16
760 0,0001 232,12 5E-09 5,34E-05 2,97E-06 1,1606E-10 6,19851E-15 3,45E-16
765 0 234,57 5E-09 5,71E-05 3,81E-06 0 0 0,00E+00
770 0 237,01 5E-09 3,81E-05 4,89E-06 0 0 0,00E+00
775 0 239,35 5E-09 3,96E-05 5,85E-06 0 0 0,00E+00
780 0 241,68 5E-09 3,17E-05 6,97E-06 0 0 0,00E+00
∑D=1,08E-5 ∑∏3=1,22E-06 ∑∏13=5,17E-11
Table 21 Calculation of luminous transmittance
Where ζ3 = The measured transmittance of the light state
ζ13 = The measured transmittance of the dark state
D = V(λ).S(λ).∆λ
∏3 = V(λ).S(λ). ζ3.∆λ
∏13 = V(λ).S(λ). ζ13.∆λ
Λ(nm) L(λ) L(λ).V(λ).∆λ L(λ).V(λ).ζ3(λ).∆λ
380 14154281670 0 0
385 14154281670 0,007077141 -1,67268E-09
390 14154281670 0,007077141 -4,0835E-08
395 14154281670 0,014154282 -3,34197E-08
400 14154281670 0,028308563 2,25134E-06
405 14154281670 0,042462845 8,27275E-06
410 14154281670 0,08492569 4,03286E-05
415 14154281670 0,155697098 0,000109121
420 14154281670 0,283085633 0,000239082
425 14154281670 0,516631281 0,000541935
430 14154281670 0,820948337 0,000999303
435 14154281670 1,18895966 0,001697114
440 14154281670 1,627742392 0,002864017
445 14154281670 2,108987969 0,004498076
450 14154281670 2,689313517 0,006848095
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455 14154281670 3,397027601 0,011118213
460 14154281670 4,246284501 0,017553708
465 14154281670 5,230007077 0,027985296
470 14154281670 6,44019816 0,047111625
475 14154281670 7,96886058 0,0785062
480 14154281670 9,837225761 0,131692419
485 14154281670 11,98159943 0,230589586
490 14154281670 14,72045294 0,411648003
495 14154281670 18,3014862 0,741329936
500 14154281670 22,8591649 1,355102135
505 14154281670 28,82519462 2,535918802
510 14154281670 35,5980184 4,328002999
515 14154281670 43,04317056 6,359788584
520 14154281670 50,24769993 8,218920133
525 14154281670 56,1358811 9,704214951
530 14154281670 61,004954 10,41705946
535 14154281670 64,7487615 10,36987005
540 14154281670 67,51592357 10,0974477
545 14154281670 69,37721161 10,20261495
550 14154281670 70,41755131 10,31682644
555 14154281670 70,77140835 10,28395475
560 14154281670 70,41755131 9,86669648
565 14154281670 69,25690021 9,427579159
570 14154281670 67,37438075 8,979543142
575 14154281670 64,7841472 8,334193716
580 14154281670 61,57112527 7,488766263
585 14154281670 57,77070064 6,432534876
590 14154281670 53,57395612 5,503309558
595 14154281670 49,17905166 4,773461494
600 14154281670 44,65675867 4,139447073
605 14154281670 40,11323425 3,606087856
610 14154281670 35,5980184 3,087348442
615 14154281670 31,22434536 2,589024021
620 14154281670 26,96390658 2,120644333
625 14154281670 22,71762208 1,620234016
630 14154281670 18,75442321 1,122698986
635 14154281670 15,35739561 0,709632342
640 14154281670 12,38499646 0,407469789
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645 14154281670 9,780608634 0,218237886
650 14154281670 7,572540694 0,113819346
655 14154281670 5,774946921 0,058920522
660 14154281670 4,317055909 0,030142849
665 14154281670 3,156404812 0,015548296
670 14154281670 2,264685067 0,007869668
675 14154281670 1,641896674 0,003996032
680 14154281670 1,203113942 0,002202074
685 14154281670 0,842179759 0,00114236
690 14154281670 0,580325548 0,000605527
695 14154281670 0,403397028 0,000324504
700 14154281670 0,290162774 0,000180576
705 14154281670 0,205237084 9,50756E-05
710 14154281670 0,148619958 5,59864E-05
715 14154281670 0,106157113 3,28971E-05
720 14154281670 0,070771408 1,79297E-05
725 14154281670 0,049539986 1,01901E-05
730 14154281670 0,035385704 6,46712E-06
735 14154281670 0,028308563 4,46732E-06
740 14154281670 0,014154282 1,79173E-06
745 14154281670 0,014154282 1,31098E-06
750 14154281670 0,007077141 7,44852E-07
755 14154281670 0,007077141 5,44322E-07
760 14154281670 0,007077141 3,77974E-07
765 14154281670 0 0
770 14154281670 0 0
775 14154281670 0 0
780 14154281670 0 0
∑( )=1512,46 ∑( )=176,57
Table 24 Calculation of Comfort Factor
λ(nm) L(λ) B(λ) ∆λ L(λ).B(λ).∆λ
300 71959887 0,01 5E-09 0,003597994
305 71959887 0,01 5E-09 0,003597994
310 71959887 0,01 5E-09 0,003597994
315 71959887 0,01 5E-09 0,003597994
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320 71959887 0,01 5E-09 0,003597994
325 71959887 0,01 5E-09 0,003597994
330 71959887 0,01 5E-09 0,003597994
335 71959887 0,01 5E-09 0,003597994
340 71959887 0,01 5E-09 0,003597994
345 71959887 0,01 5E-09 0,003597994
350 71959887 0,01 5E-09 0,003597994
355 71959887 0,01 5E-09 0,003597994
360 71959887 0,01 5E-09 0,003597994
365 71959887 0,01 5E-09 0,003597994
370 71959887 0,01 5E-09 0,003597994
375 71959887 0,01 5E-09 0,003597994
380 71959887 0,01 5E-09 0,003597994
385 71959887 0,013 5E-09 0,004677393
390 71959887 0,025 5E-09 0,008994986
395 71959887 0,05 5E-09 0,017989972
400 71959887 0,1 5E-09 0,035979944
405 71959887 0,2 5E-09 0,071959887
410 71959887 0,4 5E-09 0,143919775
415 71959887 0,8 5E-09 0,28783955
420 71959887 0,9 5E-09 0,323819493
425 71959887 0,95 5E-09 0,341809465
430 71959887 0,98 5E-09 0,352603448
435 71959887 1 5E-09 0,359799437
440 71959887 1 5E-09 0,359799437
445 71959887 0,97 5E-09 0,349005454
450 71959887 0,94 5E-09 0,338211471
455 71959887 0,9 5E-09 0,323819493
460 71959887 0,8 5E-09 0,28783955
465 71959887 0,7 5E-09 0,251859606
470 71959887 0,62 5E-09 0,223075651
475 71959887 0,55 5E-09 0,19788969
480 71959887 0,45 5E-09 0,161909747
485 71959887 0,32 5E-09 0,11513582
490 71959887 0,22 5E-09 0,079155876
495 71959887 0,16 5E-09 0,05756791
500 71959887 0,1 5E-09 0,035979944
505 71959887 0,079433 5E-09 0,028579885
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510 71959887 0,063096 5E-09 0,02270181
515 71959887 0,050119 5E-09 0,018032688
520 71959887 0,039811 5E-09 0,014323874
525 71959887 0,031623 5E-09 0,011377857
530 71959887 0,025119 5E-09 0,009037753
535 71959887 0,019953 5E-09 0,007178943
540 71959887 0,015849 5E-09 0,005702437
545 71959887 0,012589 5E-09 0,004529607
550 71959887 0,01 5E-09 0,003597994
555 71959887 0,007943 5E-09 0,002857989
560 71959887 0,00631 5E-09 0,002270181
565 71959887 0,005012 5E-09 0,001803269
570 71959887 0,003981 5E-09 0,001432387
575 71959887 0,003162 5E-09 0,001137786
580 71959887 0,002512 5E-09 0,000903775
585 71959887 0,001995 5E-09 0,000717894
590 71959887 0,001585 5E-09 0,000570244
595 71959887 0,001259 5E-09 0,000452961
600 71959887 0,001 5E-09 0,000359799
605 71959887 0,001 5E-09 0,000359799
610 71959887 0,001 5E-09 0,000359799
615 71959887 0,001 5E-09 0,000359799
620 71959887 0,001 5E-09 0,000359799
625 71959887 0,001 5E-09 0,000359799
630 71959887 0,001 5E-09 0,000359799
635 71959887 0,001 5E-09 0,000359799
640 71959887 0,001 5E-09 0,000359799
645 71959887 0,001 5E-09 0,000359799
650 71959887 0,001 5E-09 0,000359799
655 71959887 0,001 5E-09 0,000359799
660 71959887 0,001 5E-09 0,000359799
665 71959887 0,001 5E-09 0,000359799
670 71959887 0,001 5E-09 0,000359799
675 71959887 0,001 5E-09 0,000359799
680 71959887 0,001 5E-09 0,000359799
685 71959887 0,001 5E-09 0,000359799
690 71959887 0,001 5E-09 0,000359799
695 71959887 0,001 5E-09 0,000359799
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700 71959887 0,001 5E-09 0,000359799
∑( ) =4,94
Table 25 Calculation of LB
λ(nm) ζ3 B(λ) ∆λ B(λ).∆λ ζ3(λ).B(λ).∆λ
300 5,69E-06 0,01 5E-09 5E-11 2,84497E-16
305 4,02E-06 0,01 5E-09 5E-11 2,00794E-16
310 1,88E-06 0,01 5E-09 5E-11 9,39061E-17
315 1,07E-05 0,01 5E-09 5E-11 5,33604E-16
320 3,56E-06 0,01 5E-09 5E-11 1,77895E-16
325 -3,2E-06 0,01 5E-09 5E-11 -1,60496E-16
330 -6,7E-07 0,01 5E-09 5E-11 -3,32579E-17
335 -1,7E-07 0,01 5E-09 5E-11 -8,5698E-18
340 2,09E-05 0,01 5E-09 5E-11 1,04373E-15
345 4,26E-08 0,01 5E-09 5E-11 2,13229E-18
350 -1,8E-06 0,01 5E-09 5E-11 -8,93657E-17
355 4,15E-06 0,01 5E-09 5E-11 2,07578E-16
360 3,64E-06 0,01 5E-09 5E-11 1,82168E-16
365 -2,9E-06 0,01 5E-09 5E-11 -1,47321E-16
370 1,54E-05 0,01 5E-09 5E-11 7,68111E-16
375 -6,9E-06 0,01 5E-09 5E-11 -3,42965E-16
380 2,54E-06 0,01 5E-09 5E-11 1,27203E-16
385 -2,4E-07 0,013 5E-09 6,5E-11 -1,53627E-17
390 -5,8E-06 0,025 5E-09 1,25E-10 -7,21248E-16
395 -2,4E-06 0,05 5E-09 2,5E-10 -5,90276E-16
400 7,95E-05 0,1 5E-09 5E-10 3,97642E-14
405 0,000195 0,2 5E-09 0,000000001 1,94823E-13
410 0,000475 0,4 5E-09 0,000000002 9,49738E-13
415 0,000701 0,8 5E-09 0,000000004 2,80341E-12
420 0,000845 0,9 5E-09 4,5E-09 3,8005E-12
425 0,001049 0,95 5E-09 4,75E-09 4,98265E-12
430 0,001217 0,98 5E-09 4,9E-09 5,96455E-12
435 0,001427 1 5E-09 0,000000005 7,13697E-12
440 0,00176 1 5E-09 0,000000005 8,79751E-12
445 0,002133 0,97 5E-09 4,85E-09 1,03441E-11
450 0,002546 0,94 5E-09 4,7E-09 1,19681E-11
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455 0,003273 0,9 5E-09 4,5E-09 1,47282E-11
460 0,004134 0,8 5E-09 0,000000004 1,65356E-11
465 0,005351 0,7 5E-09 3,5E-09 1,87282E-11
470 0,007315 0,62 5E-09 3,1E-09 2,26773E-11
475 0,009852 0,55 5E-09 2,75E-09 2,7092E-11
480 0,013387 0,45 5E-09 2,25E-09 3,01211E-11
485 0,019245 0,32 5E-09 1,6E-09 3,07925E-11
490 0,027964 0,22 5E-09 1,1E-09 3,07608E-11
495 0,040507 0,16 5E-09 8E-10 3,24052E-11
500 0,05928 0,1 5E-09 5E-10 2,96402E-11
505 0,087976 0,079433 5E-09 3,97164E-10 3,49408E-11
510 0,12158 0,063096 5E-09 3,15479E-10 3,83559E-11
515 0,147754 0,050119 5E-09 2,50594E-10 3,70261E-11
520 0,163568 0,039811 5E-09 1,99054E-10 3,25588E-11
525 0,17287 0,031623 5E-09 1,58114E-10 2,73332E-11
530 0,170758 0,025119 5E-09 1,25594E-10 2,14462E-11
535 0,160155 0,019953 5E-09 9,97631E-11 1,59776E-11
540 0,149557 0,015849 5E-09 7,92447E-11 1,18516E-11
545 0,14706 0,012589 5E-09 6,29463E-11 9,25688E-12
550 0,146509 0,01 5E-09 5E-11 7,32547E-12
555 0,145312 0,007943 5E-09 3,97164E-11 5,77128E-12
560 0,140117 0,00631 5E-09 3,15479E-11 4,42039E-12
565 0,136125 0,005012 5E-09 2,50594E-11 3,4112E-12
570 0,133278 0,003981 5E-09 1,99054E-11 2,65295E-12
575 0,128646 0,003162 5E-09 1,58114E-11 2,03407E-12
580 0,121628 0,002512 5E-09 1,25594E-11 1,52758E-12
585 0,111346 0,001995 5E-09 9,97631E-12 1,11082E-12
590 0,102724 0,001585 5E-09 7,92447E-12 8,1403E-13
595 0,097063 0,001259 5E-09 6,29463E-12 6,10975E-13
600 0,092695 0,001 5E-09 5E-12 4,63474E-13
605 0,089898 0,001 5E-09 5E-12 4,49489E-13
610 0,086728 0,001 5E-09 5E-12 4,3364E-13
615 0,082917 0,001 5E-09 5E-12 4,14584E-13
620 0,078648 0,001 5E-09 5E-12 3,93238E-13
625 0,071321 0,001 5E-09 5E-12 3,56603E-13
630 0,059863 0,001 5E-09 5E-12 2,99316E-13
635 0,046208 0,001 5E-09 5E-12 2,31039E-13
640 0,0329 0,001 5E-09 5E-12 1,64501E-13
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645 0,022313 0,001 5E-09 5E-12 1,11567E-13
650 0,015031 0,001 5E-09 5E-12 7,51527E-14
655 0,010203 0,001 5E-09 5E-12 5,10139E-14
660 0,006982 0,001 5E-09 5E-12 3,49113E-14
665 0,004926 0,001 5E-09 5E-12 2,46298E-14
670 0,003475 0,001 5E-09 5E-12 1,73748E-14
675 0,002434 0,001 5E-09 5E-12 1,2169E-14
680 0,00183 0,001 5E-09 5E-12 9,15156E-15
685 0,001356 0,001 5E-09 5E-12 6,78216E-15
690 0,001043 0,001 5E-09 5E-12 5,21713E-15
695 0,000804 0,001 5E-09 5E-12 4,02214E-15
700 0,000622 0,001 5E-09 5E-12 3,11163E-15
∑( )=6,86E-08 ∑( )=5,73E-10
Table 26 Calculation of TB3
λ(nm) L(λ) B(λ) ζ3 ∆λ L(λ).B(λ).∆λ L(λ).B(λ).ζ(λ).∆λ
300 71959887 0,01 5,69E-06 5E-09 0,003598 2,04723E-08
305 71959887 0,01 4,02E-06 5E-09 0,003598 1,44491E-08
310 71959887 0,01 1,88E-06 5E-09 0,003598 6,75747E-09
315 71959887 0,01 1,07E-05 5E-09 0,003598 3,83981E-08
320 71959887 0,01 3,56E-06 5E-09 0,003598 1,28013E-08
325 71959887 0,01 -3,2E-06 5E-09 0,003598 -1,1549E-08
330 71959887 0,01 -6,7E-07 5E-09 0,003598 -2,3932E-09
335 71959887 0,01 -1,7E-07 5E-09 0,003598 -6,1668E-10
340 71959887 0,01 2,09E-05 5E-09 0,003598 7,51064E-08
345 71959887 0,01 4,26E-08 5E-09 0,003598 1,53439E-10
350 71959887 0,01 -1,8E-06 5E-09 0,003598 -6,4307E-09
355 71959887 0,01 4,15E-06 5E-09 0,003598 1,49373E-08
360 71959887 0,01 3,64E-06 5E-09 0,003598 1,31088E-08
365 71959887 0,01 -2,9E-06 5E-09 0,003598 -1,0601E-08
370 71959887 0,01 1,54E-05 5E-09 0,003598 5,52732E-08
375 71959887 0,01 -6,9E-06 5E-09 0,003598 -2,468E-08
380 71959887 0,01 2,54E-06 5E-09 0,003598 9,1535E-09
385 71959887 0,013 -2,4E-07 5E-09 0,004677 -1,1055E-09
390 71959887 0,025 -5,8E-06 5E-09 0,008995 -5,1901E-08
395 71959887 0,05 -2,4E-06 5E-09 0,01799 -4,2476E-08
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400 71959887 0,1 7,95E-05 5E-09 0,03598 2,86143E-06
405 71959887 0,2 0,000195 5E-09 0,07196 1,40195E-05
410 71959887 0,4 0,000475 5E-09 0,14392 6,8343E-05
415 71959887 0,8 0,000701 5E-09 0,28784 0,000201733
420 71959887 0,9 0,000845 5E-09 0,323819 0,000273484
425 71959887 0,95 0,001049 5E-09 0,341809 0,000358551
430 71959887 0,98 0,001217 5E-09 0,352603 0,000429208
435 71959887 1 0,001427 5E-09 0,359799 0,000513576
440 71959887 1 0,00176 5E-09 0,359799 0,000633068
445 71959887 0,97 0,002133 5E-09 0,349005 0,000744363
450 71959887 0,94 0,002546 5E-09 0,338211 0,000861225
455 71959887 0,9 0,003273 5E-09 0,323819 0,001059837
460 71959887 0,8 0,004134 5E-09 0,28784 0,001189899
465 71959887 0,7 0,005351 5E-09 0,25186 0,001347678
470 71959887 0,62 0,007315 5E-09 0,223076 0,001631853
475 71959887 0,55 0,009852 5E-09 0,19789 0,001949534
480 71959887 0,45 0,013387 5E-09 0,16191 0,00216751
485 71959887 0,32 0,019245 5E-09 0,115136 0,002215824
490 71959887 0,22 0,027964 5E-09 0,079156 0,002213543
495 71959887 0,16 0,040507 5E-09 0,057568 0,002331877
500 71959887 0,1 0,05928 5E-09 0,03598 0,002132908
505 71959887 0,079433 0,087976 5E-09 0,02858 0,002514337
510 71959887 0,063096 0,12158 5E-09 0,022702 0,002760083
515 71959887 0,050119 0,147754 5E-09 0,018033 0,002664397
520 71959887 0,039811 0,163568 5E-09 0,014324 0,002342929
525 71959887 0,031623 0,17287 5E-09 0,011378 0,001966891
530 71959887 0,025119 0,170758 5E-09 0,009038 0,001543265
535 71959887 0,019953 0,160155 5E-09 0,007179 0,001149747
540 71959887 0,015849 0,149557 5E-09 0,005702 0,000852837
545 71959887 0,012589 0,14706 5E-09 0,00453 0,000666124
550 71959887 0,01 0,146509 5E-09 0,003598 0,00052714
555 71959887 0,007943 0,145312 5E-09 0,002858 0,000415301
560 71959887 0,00631 0,140117 5E-09 0,00227 0,000318091
565 71959887 0,005012 0,136125 5E-09 0,001803 0,00024547
570 71959887 0,003981 0,133278 5E-09 0,001432 0,000190906
575 71959887 0,003162 0,128646 5E-09 0,001138 0,000146371
580 71959887 0,002512 0,121628 5E-09 0,000904 0,000109924
585 71959887 0,001995 0,111346 5E-09 0,000718 7,99346E-05
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590 71959887 0,001585 0,102724 5E-09 0,00057 5,85775E-05
595 71959887 0,001259 0,097063 5E-09 0,000453 4,39657E-05
600 71959887 0,001 0,092695 5E-09 0,00036 3,33515E-05
605 71959887 0,001 0,089898 5E-09 0,00036 3,23451E-05
610 71959887 0,001 0,086728 5E-09 0,00036 3,12047E-05
615 71959887 0,001 0,082917 5E-09 0,00036 2,98334E-05
620 71959887 0,001 0,078648 5E-09 0,00036 2,82973E-05
625 71959887 0,001 0,071321 5E-09 0,00036 2,56611E-05
630 71959887 0,001 0,059863 5E-09 0,00036 2,15387E-05
635 71959887 0,001 0,046208 5E-09 0,00036 1,66256E-05
640 71959887 0,001 0,0329 5E-09 0,00036 1,18375E-05
645 71959887 0,001 0,022313 5E-09 0,00036 8,02832E-06
650 71959887 0,001 0,015031 5E-09 0,00036 5,40798E-06
655 71959887 0,001 0,010203 5E-09 0,00036 3,67096E-06
660 71959887 0,001 0,006982 5E-09 0,00036 2,51222E-06
665 71959887 0,001 0,004926 5E-09 0,00036 1,77235E-06
670 71959887 0,001 0,003475 5E-09 0,00036 1,25029E-06
675 71959887 0,001 0,002434 5E-09 0,00036 8,75676E-07
680 71959887 0,001 0,00183 5E-09 0,00036 6,58545E-07
685 71959887 0,001 0,001356 5E-09 0,00036 4,88044E-07
690 71959887 0,001 0,001043 5E-09 0,00036 3,75424E-07
695 71959887 0,001 0,000804 5E-09 0,00036 2,89433E-07
700 71959887 0,001 0,000622 5E-09 0,00036 2,23913E-07
∑( ) =4,94 ∑( ) =4,12E-2
Table 27 Calculation of PFBLPH
λ(nm) L(λ) B(λ) ∆λ L(λ).B(λ).∆λ
300 1,39E+12 0,01 5E-09 69,46128024
305 1,39E+12 0,01 5E-09 69,46128024
310 1,39E+12 0,01 5E-09 69,46128024
315 1,39E+12 0,01 5E-09 69,46128024
320 1,39E+12 0,01 5E-09 69,46128024
325 1,39E+12 0,01 5E-09 69,46128024
330 1,39E+12 0,01 5E-09 69,46128024
335 1,39E+12 0,01 5E-09 69,46128024
340 1,39E+12 0,01 5E-09 69,46128024
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345 1,39E+12 0,01 5E-09 69,46128024
350 1,39E+12 0,01 5E-09 69,46128024
355 1,39E+12 0,01 5E-09 69,46128024
360 1,39E+12 0,01 5E-09 69,46128024
365 1,39E+12 0,01 5E-09 69,46128024
370 1,39E+12 0,01 5E-09 69,46128024
375 1,39E+12 0,01 5E-09 69,46128024
380 1,39E+12 0,01 5E-09 69,46128024
385 1,39E+12 0,013 5E-09 90,29966431
390 1,39E+12 0,025 5E-09 173,6532006
395 1,39E+12 0,05 5E-09 347,3064012
400 1,39E+12 0,1 5E-09 694,6128024
405 1,39E+12 0,2 5E-09 1389,225605
410 1,39E+12 0,4 5E-09 2778,45121
415 1,39E+12 0,8 5E-09 5556,902419
420 1,39E+12 0,9 5E-09 6251,515222
425 1,39E+12 0,95 5E-09 6598,821623
430 1,39E+12 0,98 5E-09 6807,205464
435 1,39E+12 1 5E-09 6946,128024
440 1,39E+12 1 5E-09 6946,128024
445 1,39E+12 0,97 5E-09 6737,744183
450 1,39E+12 0,94 5E-09 6529,360343
455 1,39E+12 0,9 5E-09 6251,515222
460 1,39E+12 0,8 5E-09 5556,902419
465 1,39E+12 0,7 5E-09 4862,289617
470 1,39E+12 0,62 5E-09 4306,599375
475 1,39E+12 0,55 5E-09 3820,370413
480 1,39E+12 0,45 5E-09 3125,757611
485 1,39E+12 0,32 5E-09 2222,760968
490 1,39E+12 0,22 5E-09 1528,148165
495 1,39E+12 0,16 5E-09 1111,380484
500 1,39E+12 0,1 5E-09 694,6128024
505 1,39E+12 0,079433 5E-09 551,7505612
510 1,39E+12 0,063096 5E-09 438,2710493
515 1,39E+12 0,050119 5E-09 348,1310689
520 1,39E+12 0,039811 5E-09 276,5303374
525 1,39E+12 0,031623 5E-09 219,6558548
530 1,39E+12 0,025119 5E-09 174,4788474
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535 1,39E+12 0,019953 5E-09 138,5934748
540 1,39E+12 0,015849 5E-09 110,0887102
545 1,39E+12 0,012589 5E-09 87,44657083
550 1,39E+12 0,01 5E-09 69,46128024
555 1,39E+12 0,007943 5E-09 55,17505612
560 1,39E+12 0,00631 5E-09 43,82710493
565 1,39E+12 0,005012 5E-09 34,81310689
570 1,39E+12 0,003981 5E-09 27,65303374
575 1,39E+12 0,003162 5E-09 21,96558548
580 1,39E+12 0,002512 5E-09 17,44788474
585 1,39E+12 0,001995 5E-09 13,85934748
590 1,39E+12 0,001585 5E-09 11,00887102
595 1,39E+12 0,001259 5E-09 8,744657083
600 1,39E+12 0,001 5E-09 6,946128024
605 1,39E+12 0,001 5E-09 6,946128024
610 1,39E+12 0,001 5E-09 6,946128024
615 1,39E+12 0,001 5E-09 6,946128024
620 1,39E+12 0,001 5E-09 6,946128024
625 1,39E+12 0,001 5E-09 6,946128024
630 1,39E+12 0,001 5E-09 6,946128024
635 1,39E+12 0,001 5E-09 6,946128024
640 1,39E+12 0,001 5E-09 6,946128024
645 1,39E+12 0,001 5E-09 6,946128024
650 1,39E+12 0,001 5E-09 6,946128024
655 1,39E+12 0,001 5E-09 6,946128024
660 1,39E+12 0,001 5E-09 6,946128024
665 1,39E+12 0,001 5E-09 6,946128024
670 1,39E+12 0,001 5E-09 6,946128024
675 1,39E+12 0,001 5E-09 6,946128024
680 1,39E+12 0,001 5E-09 6,946128024
685 1,39E+12 0,001 5E-09 6,946128024
690 1,39E+12 0,001 5E-09 6,946128024
695 1,39E+12 0,001 5E-09 6,946128024
700 1,39E+12 0,001 5E-09 6,946128024
∑( ) =9,54E+4
Table 28 Calculation of LB
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λ(nm) L(λ) R(λ) ∆λ L(λ).R(λ).∆λ
380 71959887 0,1 5E-09 0,035979944
385 71959887 0,13 5E-09 0,046773927
390 71959887 0,25 5E-09 0,089949859
395 71959887 0,5 5E-09 0,179899718
400 71959887 1 5E-09 0,359799435
405 71959887 2 5E-09 0,71959887
410 71959887 4 5E-09 1,43919774
415 71959887 8 5E-09 2,87839548
420 71959887 9 5E-09 3,238194915
425 71959887 9,5 5E-09 3,418094633
430 71959887 9,8 5E-09 3,526034463
435 71959887 10 5E-09 3,59799435
440 71959887 10 5E-09 3,59799435
445 71959887 9,7 5E-09 3,49005452
450 71959887 9,4 5E-09 3,382114689
455 71959887 9 5E-09 3,238194915
460 71959887 8 5E-09 2,87839548
465 71959887 7 5E-09 2,518596045
470 71959887 6,2 5E-09 2,230756497
475 71959887 5,5 5E-09 1,978896893
480 71959887 4,5 5E-09 1,619097458
485 71959887 3,2 5E-09 1,151358192
490 71959887 2,2 5E-09 0,791558757
495 71959887 1,6 5E-09 0,575679096
500 71959887 1 5E-09 0,359799435
505 71959887 1 5E-09 0,359799435
510 71959887 1 5E-09 0,359799435
515 71959887 1 5E-09 0,359799435
520 71959887 1 5E-09 0,359799435
525 71959887 1 5E-09 0,359799435
530 71959887 1 5E-09 0,359799435
535 71959887 1 5E-09 0,359799435
540 71959887 1 5E-09 0,359799435
545 71959887 1 5E-09 0,359799435
550 71959887 1 5E-09 0,359799435
555 71959887 1 5E-09 0,359799435
560 71959887 1 5E-09 0,359799435
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565 71959887 1 5E-09 0,359799435
570 71959887 1 5E-09 0,359799435
575 71959887 1 5E-09 0,359799435
580 71959887 1 5E-09 0,359799435
585 71959887 1 5E-09 0,359799435
590 71959887 1 5E-09 0,359799435
595 71959887 1 5E-09 0,359799435
600 71959887 1 5E-09 0,359799435
605 71959887 1 5E-09 0,359799435
610 71959887 1 5E-09 0,359799435
615 71959887 1 5E-09 0,359799435
620 71959887 1 5E-09 0,359799435
625 71959887 1 5E-09 0,359799435
630 71959887 1 5E-09 0,359799435
635 71959887 1 5E-09 0,359799435
640 71959887 1 5E-09 0,359799435
645 71959887 1 5E-09 0,359799435
650 71959887 1 5E-09 0,359799435
655 71959887 1 5E-09 0,359799435
660 71959887 1 5E-09 0,359799435
665 71959887 1 5E-09 0,359799435
670 71959887 1 5E-09 0,359799435
675 71959887 1 5E-09 0,359799435
680 71959887 1 5E-09 0,359799435
685 71959887 1 5E-09 0,359799435
690 71959887 1 5E-09 0,359799435
695 71959887 1 5E-09 0,359799435
700 71959887 1 5E-09 0,359799435
705 71959887 0,977237 5E-09 0,3516094
710 71959887 0,954993 5E-09 0,343605793
715 71959887 0,933254 5E-09 0,33578437
720 71959887 0,912011 5E-09 0,328140985
725 71959887 0,891251 5E-09 0,320671584
730 71959887 0,870964 5E-09 0,313372208
735 71959887 0,851138 5E-09 0,306238985
740 71959887 0,831764 5E-09 0,299268135
745 71959887 0,812831 5E-09 0,29245596
750 71959887 0,794328 5E-09 0,28579885
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755 71959887 0,776247 5E-09 0,279293274
760 71959887 0,758578 5E-09 0,272935783
765 71959887 0,74131 5E-09 0,266723006
770 71959887 0,724436 5E-09 0,260651649
775 71959887 0,707946 5E-09 0,254718493
780 71959887 0,691831 5E-09 0,248920392
790 71959887 0,660693 1E-08 0,475434259
800 71959887 0,630957 1E-08 0,454036192
810 71959887 0,60256 1E-08 0,433601197
820 71959887 0,57544 1E-08 0,414085929
830 71959887 0,549541 1E-08 0,395448992
840 71959887 0,524807 1E-08 0,377650855
850 71959887 0,501187 1E-08 0,360653767
860 71959887 0,47863 1E-08 0,344421674
870 71959887 0,457088 1E-08 0,328920145
880 71959887 0,436516 1E-08 0,3141163
890 71959887 0,416869 1E-08 0,299978737
900 71959887 0,398107 1E-08 0,28647747
910 71959887 0,380189 1E-08 0,27358386
920 71959887 0,363078 1E-08 0,261270558
930 71959887 0,346737 1E-08 0,249511446
940 71959887 0,331131 1E-08 0,238281581
950 71959887 0,316228 1E-08 0,227557143
960 71959887 0,301995 1E-08 0,217315385
970 71959887 0,288403 1E-08 0,207534581
980 71959887 0,275423 1E-08 0,198193986
990 71959887 0,263027 1E-08 0,189273787
1000 71959887 0,251189 1E-08 0,180755064
1010 71959887 0,239883 1E-08 0,172619746
1020 71959887 0,229087 1E-08 0,164850577
1030 71959887 0,218776 1E-08 0,157431079
1040 71959887 0,20893 1E-08 0,150345513
1050 71959887 0,199526 1E-08 0,143578851
1060 71959887 0,2 1E-08 0,143919774
1070 71959887 0,2 1E-08 0,143919774
1080 71959887 0,2 1E-08 0,143919774
1090 71959887 0,2 1E-08 0,143919774
1100 71959887 0,2 1E-08 0,143919774
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1110 71959887 0,2 1E-08 0,143919774
1120 71959887 0,2 1E-08 0,143919774
1130 71959887 0,2 1E-08 0,143919774
1140 71959887 0,2 1E-08 0,143919774
1150 71959887 0,2 1E-08 0,143919774
1160 71959887 0,126191 1E-08 0,090807238
1170 71959887 0,079621 1E-08 0,057295494
1180 71959887 0,050238 1E-08 0,036151013
1190 71959887 0,031698 1E-08 0,022809747
1200 71959887 0,02 1E-08 0,014391977
1210 71959887 0,02 1E-08 0,014391977
1220 71959887 0,02 1E-08 0,014391977
1230 71959887 0,02 1E-08 0,014391977
1240 71959887 0,02 1E-08 0,014391977
1250 71959887 0,02 1E-08 0,014391977
1260 71959887 0,02 1E-08 0,014391977
1270 71959887 0,02 1E-08 0,014391977
1280 71959887 0,02 1E-08 0,014391977
1290 71959887 0,02 1E-08 0,014391977
1300 71959887 0,02 1E-08 0,014391977
1310 71959887 0,02 1E-08 0,014391977
1320 71959887 0,02 1E-08 0,014391977
1330 71959887 0,02 1E-08 0,014391977
1340 71959887 0,02 1E-08 0,014391977
1350 71959887 0,02 1E-08 0,014391977
1360 71959887 0,02 1E-08 0,014391977
1370 71959887 0,02 1E-08 0,014391977
1380 71959887 0,02 1E-08 0,014391977
1390 71959887 0,02 1E-08 0,014391977
1400 71959887 0,02 1E-08 0,014391977
∑( )=75,96
Table 29 Calculation of LR
λ(nm) ζ3 R(λ) ∆λ R(λ).∆λ ζ3(λ).R(λ).∆λ
380 3,9E-08 0,1 5E-09 5E-10 1,95249E-17
385 4,33E-08 0,13 5E-09 6,5E-10 2,81555E-17
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390 3,27E-07 0,25 5E-09 1,25E-09 4,08882E-16
395 8,95E-06 0,5 5E-09 2,5E-09 2,23874E-14
400 7,17E-05 1 5E-09 0,000000005 3,5867E-13
405 0,000206 2 5E-09 0,00000001 2,05515E-12
410 0,000416 4 5E-09 0,00000002 8,31356E-12
415 0,000573 8 5E-09 0,00000004 2,294E-11
420 0,000728 9 5E-09 0,000000045 3,27511E-11
425 0,000912 9,5 5E-09 4,75E-08 4,33213E-11
430 0,00099 9,8 5E-09 0,000000049 4,84885E-11
435 0,001257 10 5E-09 0,00000005 6,28477E-11
440 0,001502 10 5E-09 0,00000005 7,50917E-11
445 0,001723 9,7 5E-09 4,85E-08 8,35698E-11
450 0,002212 9,4 5E-09 0,000000047 1,03986E-10
455 0,002803 9 5E-09 0,000000045 1,26156E-10
460 0,003452 8 5E-09 0,00000004 1,38096E-10
465 0,004582 7 5E-09 0,000000035 1,60358E-10
470 0,006205 6,2 5E-09 0,000000031 1,92368E-10
475 0,008121 5,5 5E-09 2,75E-08 2,23336E-10
480 0,01132 4,5 5E-09 2,25E-08 2,54691E-10
485 0,016289 3,2 5E-09 0,000000016 2,60622E-10
490 0,02348 2,2 5E-09 0,000000011 2,58281E-10
495 0,033501 1,6 5E-09 0,000000008 2,6801E-10
500 0,051426 1 5E-09 0,000000005 2,57131E-10
505 0,076005 1 5E-09 0,000000005 3,80023E-10
510 0,104725 1 5E-09 0,000000005 5,23627E-10
515 0,129771 1 5E-09 0,000000005 6,48854E-10
520 0,149814 1 5E-09 0,000000005 7,4907E-10
525 0,160977 1 5E-09 0,000000005 8,04886E-10
530 0,15762 1 5E-09 0,000000005 7,881E-10
535 0,15762 1 5E-09 0,000000005 7,881E-10
540 0,15762 1 5E-09 0,000000005 7,881E-10
545 0,15762 1 5E-09 0,000000005 7,881E-10
550 0,15762 1 5E-09 0,000000005 7,881E-10
555 0,15762 1 5E-09 0,000000005 7,881E-10
560 0,15762 1 5E-09 0,000000005 7,881E-10
565 0,15762 1 5E-09 0,000000005 7,881E-10
570 0,15762 1 5E-09 0,000000005 7,881E-10
575 0,15762 1 5E-09 0,000000005 7,881E-10
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580 0,15762 1 5E-09 0,000000005 7,881E-10
585 0,15762 1 5E-09 0,000000005 7,881E-10
590 0,15762 1 5E-09 0,000000005 7,881E-10
595 0,15762 1 5E-09 0,000000005 7,881E-10
600 0,15762 1 5E-09 0,000000005 7,881E-10
605 0,15762 1 5E-09 0,000000005 7,881E-10
610 0,15762 1 5E-09 0,000000005 7,881E-10
615 0,15762 1 5E-09 0,000000005 7,881E-10
620 0,15762 1 5E-09 0,000000005 7,881E-10
625 0,15762 1 5E-09 0,000000005 7,881E-10
630 0,15762 1 5E-09 0,000000005 7,881E-10
635 0,15762 1 5E-09 0,000000005 7,881E-10
640 0,15762 1 5E-09 0,000000005 7,881E-10
645 0,15762 1 5E-09 0,000000005 7,881E-10
650 0,15762 1 5E-09 0,000000005 7,881E-10
655 0,15762 1 5E-09 0,000000005 7,881E-10
660 0,15762 1 5E-09 0,000000005 7,881E-10
665 0,15762 1 5E-09 0,000000005 7,881E-10
670 0,15762 1 5E-09 0,000000005 7,881E-10
675 0,15762 1 5E-09 0,000000005 7,881E-10
680 0,001579 1 5E-09 0,000000005 7,89401E-12
685 0,001204 1 5E-09 0,000000005 6,01951E-12
690 0,000904 1 5E-09 0,000000005 4,52177E-12
695 0,000695 1 5E-09 0,000000005 3,47287E-12
700 0,000545 1 5E-09 0,000000005 2,72437E-12
705 0,000426 0,977237 5E-09 4,88619E-09 2,07957E-12
710 0,000337 0,954993 5E-09 4,77496E-09 1,61009E-12
715 0,000271 0,933254 5E-09 4,66627E-09 1,26246E-12
720 0,000221 0,912011 5E-09 4,56005E-09 1,00824E-12
725 0,000183 0,891251 5E-09 4,45625E-09 8,1469E-13
730 0,000149 0,870964 5E-09 4,35482E-09 6,47446E-13
735 0,000125 0,851138 5E-09 4,25569E-09 5,32421E-13
740 0,000105 0,831764 5E-09 4,15882E-09 4,3683E-13
745 8,77E-05 0,812831 5E-09 4,06415E-09 3,56488E-13
750 7,43E-05 0,794328 5E-09 3,97164E-09 2,95228E-13
755 6,38E-05 0,776247 5E-09 3,88124E-09 2,47779E-13
760 5,58E-05 0,758578 5E-09 3,79289E-09 2,11496E-13
765 4,81E-05 0,74131 5E-09 3,70655E-09 1,78215E-13
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770 4,26E-05 0,724436 5E-09 3,62218E-09 1,54417E-13
775 3,81E-05 0,707946 5E-09 3,53973E-09 1,3473E-13
780 3,43E-05 0,691831 5E-09 3,45915E-09 1,18604E-13
790 2,83E-05 0,660693 1E-08 6,60693E-09 1,86858E-13
800 2,6E-05 0,630957 1E-08 6,30957E-09 1,63956E-13
810 2,9E-05 0,60256 1E-08 6,0256E-09 1,74648E-13
820 2,51E-05 0,57544 1E-08 5,7544E-09 1,44406E-13
830 2,34E-05 0,549541 1E-08 5,49541E-09 1,28546E-13
840 1,89E-05 0,524807 1E-08 5,24807E-09 9,92078E-14
850 1,82E-05 0,501187 1E-08 5,01187E-09 9,11082E-14
860 1,59E-05 0,47863 1E-08 4,7863E-09 7,59617E-14
870 1,39E-05 0,457088 1E-08 4,57088E-09 6,33991E-14
880 1,3E-05 0,436516 1E-08 4,36516E-09 5,65625E-14
890 1,18E-05 0,416869 1E-08 4,16869E-09 4,91348E-14
900 1,07E-05 0,398107 1E-08 3,98107E-09 4,26363E-14
910 8,75E-06 0,380189 1E-08 3,80189E-09 3,32607E-14
920 7,43E-06 0,363078 1E-08 3,63078E-09 2,69592E-14
930 6,63E-06 0,346737 1E-08 3,46737E-09 2,29738E-14
940 6,84E-06 0,331131 1E-08 3,31131E-09 2,26632E-14
950 5,11E-06 0,316228 1E-08 3,16228E-09 1,6158E-14
960 5,29E-06 0,301995 1E-08 3,01995E-09 1,59672E-14
970 4,72E-06 0,288403 1E-08 2,88403E-09 1,361E-14
980 3,82E-06 0,275423 1E-08 2,75423E-09 1,05252E-14
990 3,41E-06 0,263027 1E-08 2,63027E-09 8,96986E-15
1000 3,42E-06 0,251189 1E-08 2,51189E-09 8,5984E-15
1010 2,83E-06 0,239883 1E-08 2,39883E-09 6,77921E-15
1020 2,39E-06 0,229087 1E-08 2,29087E-09 5,4663E-15
1030 2,59E-06 0,218776 1E-08 2,18776E-09 5,66721E-15
1040 2,06E-06 0,20893 1E-08 2,0893E-09 4,29702E-15
1050 2,22E-06 0,199526 1E-08 1,99526E-09 4,42601E-15
1060 1,75E-06 0,2 1E-08 0,000000002 3,49108E-15
1070 1,82E-06 0,2 1E-08 0,000000002 3,64476E-15
1080 1,69E-06 0,2 1E-08 0,000000002 3,37485E-15
1090 1,27E-06 0,2 1E-08 0,000000002 2,53532E-15
1100 1,25E-06 0,2 1E-08 0,000000002 2,5093E-15
1110 1,21E-06 0,2 1E-08 0,000000002 2,41765E-15
1120 1,39E-06 0,2 1E-08 0,000000002 2,78536E-15
1130 8,89E-07 0,2 1E-08 0,000000002 1,77881E-15
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1140 1,05E-06 0,2 1E-08 0,000000002 2,09077E-15
1150 7,3E-07 0,2 1E-08 0,000000002 1,45932E-15
1160 1,01E-06 0,126191 1E-08 1,26191E-09 1,27309E-15
1170 6,02E-07 0,079621 1E-08 7,96214E-10 4,79001E-16
1180 7,76E-07 0,050238 1E-08 5,02377E-10 3,89978E-16
1190 5,2E-07 0,031698 1E-08 3,16979E-10 1,6486E-16
1200 5,17E-07 0,02 1E-08 2E-10 1,03488E-16
1210 5,16E-07 0,02 1E-08 2E-10 1,03207E-16
1220 7,22E-07 0,02 1E-08 2E-10 1,44387E-16
1230 6,31E-07 0,02 1E-08 2E-10 1,26178E-16
1240 4,5E-07 0,02 1E-08 2E-10 8,99625E-17
1250 2,37E-07 0,02 1E-08 2E-10 4,7482E-17
1260 3,83E-07 0,02 1E-08 2E-10 7,66636E-17
1270 1,61E-07 0,02 1E-08 2E-10 3,2133E-17
1280 1,62E-07 0,02 1E-08 2E-10 3,24651E-17
1290 4,28E-07 0,02 1E-08 2E-10 8,56225E-17
1300 3,2E-07 0,02 1E-08 2E-10 6,40488E-17
1310 3,73E-07 0,02 1E-08 2E-10 7,46377E-17
1320 3,24E-07 0,02 1E-08 2E-10 6,47175E-17
1330 4,46E-07 0,02 1E-08 2E-10 8,92223E-17
1340 4,47E-07 0,02 1E-08 2E-10 8,94558E-17
1350 3,42E-07 0,02 1E-08 2E-10 6,83302E-17
1360 3,83E-07 0,02 1E-08 2E-10 7,6695E-17
1370 4,37E-08 0,02 1E-08 2E-10 8,73399E-18
1380 2,95E-07 0,02 1E-08 2E-10 5,90617E-17
1390 3,64E-08 0,02 1E-08 2E-10 7,27251E-18
1400 2,22E-07 0,02 1E-08 2E-10 4,44486E-17
∑( ) =1,06E-6 ∑( ) =2,94E-8
Table 30 Calculation of T3(V-IRA
λ(nm) L(λ) R(λ) ∆λ ζ3 L(λ).R(λ).∆λ L(λ).R(λ).ζ3(λ).∆λ
380 71959887 0,1 5E-09 3,9E-08 0,0359799 1,40501E-09
385 71959887 0,13 5E-09 4,33E-08 0,0467739 2,02607E-09
390 71959887 0,25 5E-09 3,27E-07 0,0899499 2,94231E-08
395 71959887 0,5 5E-09 8,95E-06 0,1798997 1,611E-06
400 71959887 1 5E-09 7,17E-05 0,3597994 2,58098E-05
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405 71959887 2 5E-09 0,000206 0,7195989 0,000147888
410 71959887 4 5E-09 0,000416 1,4391977 0,000598243
415 71959887 8 5E-09 0,000573 2,8783955 0,001650758
420 71959887 9 5E-09 0,000728 3,2381949 0,002356767
425 71959887 9,5 5E-09 0,000912 3,4180946 0,003117393
430 71959887 9,8 5E-09 0,00099 3,5260345 0,003489224
435 71959887 10 5E-09 0,001257 3,5979944 0,00452251
440 71959887 10 5E-09 0,001502 3,5979944 0,005403591
445 71959887 9,7 5E-09 0,001723 3,4900545 0,006013672
450 71959887 9,4 5E-09 0,002212 3,3821147 0,007482802
455 71959887 9 5E-09 0,002803 3,2381949 0,009078165
460 71959887 8 5E-09 0,003452 2,8783955 0,009937398
465 71959887 7 5E-09 0,004582 2,518596 0,011539327
470 71959887 6,2 5E-09 0,006205 2,2307565 0,013842787
475 71959887 5,5 5E-09 0,008121 1,9788969 0,016071268
480 71959887 4,5 5E-09 0,01132 1,6190975 0,01832754
485 71959887 3,2 5E-09 0,016289 1,1513582 0,018754347
490 71959887 2,2 5E-09 0,02348 0,7915588 0,01858586
495 71959887 1,6 5E-09 0,033501 0,5756791 0,019285953
500 71959887 1 5E-09 0,051426 0,3597994 0,018503108
505 71959887 1 5E-09 0,076005 0,3597994 0,027346393
510 71959887 1 5E-09 0,104725 0,3597994 0,037680128
515 71959887 1 5E-09 0,129771 0,3597994 0,046691446
520 71959887 1 5E-09 0,149814 0,3597994 0,053903018
525 71959887 1 5E-09 0,160977 0,3597994 0,057919498
530 71959887 1 5E-09 0,15762 0,3597994 0,056711584
535 71959887 1 5E-09 0,15762 0,3597994 0,056711584
540 71959887 1 5E-09 0,15762 0,3597994 0,056711584
545 71959887 1 5E-09 0,15762 0,3597994 0,056711584
550 71959887 1 5E-09 0,15762 0,3597994 0,056711584
555 71959887 1 5E-09 0,15762 0,3597994 0,056711584
560 71959887 1 5E-09 0,15762 0,3597994 0,056711584
565 71959887 1 5E-09 0,15762 0,3597994 0,056711584
570 71959887 1 5E-09 0,15762 0,3597994 0,056711584
575 71959887 1 5E-09 0,15762 0,3597994 0,056711584
580 71959887 1 5E-09 0,15762 0,3597994 0,056711584
585 71959887 1 5E-09 0,15762 0,3597994 0,056711584
590 71959887 1 5E-09 0,15762 0,3597994 0,056711584
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595 71959887 1 5E-09 0,15762 0,3597994 0,056711584
600 71959887 1 5E-09 0,15762 0,3597994 0,056711584
605 71959887 1 5E-09 0,15762 0,3597994 0,056711584
610 71959887 1 5E-09 0,15762 0,3597994 0,056711584
615 71959887 1 5E-09 0,15762 0,3597994 0,056711584
620 71959887 1 5E-09 0,15762 0,3597994 0,056711584
625 71959887 1 5E-09 0,15762 0,3597994 0,056711584
630 71959887 1 5E-09 0,15762 0,3597994 0,056711584
635 71959887 1 5E-09 0,15762 0,3597994 0,056711584
640 71959887 1 5E-09 0,15762 0,3597994 0,056711584
645 71959887 1 5E-09 0,15762 0,3597994 0,056711584
650 71959887 1 5E-09 0,15762 0,3597994 0,056711584
655 71959887 1 5E-09 0,15762 0,3597994 0,056711584
660 71959887 1 5E-09 0,15762 0,3597994 0,056711584
665 71959887 1 5E-09 0,15762 0,3597994 0,056711584
670 71959887 1 5E-09 0,15762 0,3597994 0,056711584
675 71959887 1 5E-09 0,15762 0,3597994 0,056711584
680 71959887 1 5E-09 0,001579 0,3597994 0,000568052
685 71959887 1 5E-09 0,001204 0,3597994 0,000433163
690 71959887 1 5E-09 0,000904 0,3597994 0,000325386
695 71959887 1 5E-09 0,000695 0,3597994 0,000249907
700 71959887 1 5E-09 0,000545 0,3597994 0,000196045
705 71959887 0,977237 5E-09 0,000426 0,3516094 0,000149645
710 71959887 0,954993 5E-09 0,000337 0,3436058 0,000115862
715 71959887 0,933254 5E-09 0,000271 0,3357844 9,08467E-05
720 71959887 0,912011 5E-09 0,000221 0,328141 7,25526E-05
725 71959887 0,891251 5E-09 0,000183 0,3206716 5,8625E-05
730 71959887 0,870964 5E-09 0,000149 0,3133722 4,65901E-05
735 71959887 0,851138 5E-09 0,000125 0,306239 3,8313E-05
740 71959887 0,831764 5E-09 0,000105 0,2992681 3,14343E-05
745 71959887 0,812831 5E-09 8,77E-05 0,292456 2,56528E-05
750 71959887 0,794328 5E-09 7,43E-05 0,2857989 2,12446E-05
755 71959887 0,776247 5E-09 6,38E-05 0,2792933 1,78301E-05
760 71959887 0,758578 5E-09 5,58E-05 0,2729358 1,52192E-05
765 71959887 0,74131 5E-09 4,81E-05 0,266723 1,28243E-05
770 71959887 0,724436 5E-09 4,26E-05 0,2606516 1,11119E-05
775 71959887 0,707946 5E-09 3,81E-05 0,2547185 9,69517E-06
780 71959887 0,691831 5E-09 3,43E-05 0,2489204 8,5347E-06
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790 71959887 0,660693 1E-08 2,83E-05 0,4754343 1,34463E-05
800 71959887 0,630957 1E-08 2,6E-05 0,4540362 1,17982E-05
810 71959887 0,60256 1E-08 2,9E-05 0,4336012 1,25677E-05
820 71959887 0,57544 1E-08 2,51E-05 0,4140859 1,03914E-05
830 71959887 0,549541 1E-08 2,34E-05 0,395449 9,25018E-06
840 71959887 0,524807 1E-08 1,89E-05 0,3776509 7,13898E-06
850 71959887 0,501187 1E-08 1,82E-05 0,3606538 6,55613E-06
860 71959887 0,47863 1E-08 1,59E-05 0,3444217 5,4662E-06
870 71959887 0,457088 1E-08 1,39E-05 0,3289201 4,56219E-06
880 71959887 0,436516 1E-08 1,3E-05 0,3141163 4,07023E-06
890 71959887 0,416869 1E-08 1,18E-05 0,2999787 3,53574E-06
900 71959887 0,398107 1E-08 1,07E-05 0,2864775 3,06811E-06
910 71959887 0,380189 1E-08 8,75E-06 0,2735839 2,39344E-06
920 71959887 0,363078 1E-08 7,43E-06 0,2612706 1,93998E-06
930 71959887 0,346737 1E-08 6,63E-06 0,2495114 1,65319E-06
940 71959887 0,331131 1E-08 6,84E-06 0,2382816 1,63084E-06
950 71959887 0,316228 1E-08 5,11E-06 0,2275571 1,16273E-06
960 71959887 0,301995 1E-08 5,29E-06 0,2173154 1,149E-06
970 71959887 0,288403 1E-08 4,72E-06 0,2075346 9,79376E-07
980 71959887 0,275423 1E-08 3,82E-06 0,198194 7,57393E-07
990 71959887 0,263027 1E-08 3,41E-06 0,1892738 6,4547E-07
1000 71959887 0,251189 1E-08 3,42E-06 0,1807551 6,1874E-07
1010 71959887 0,239883 1E-08 2,83E-06 0,1726197 4,87831E-07
1020 71959887 0,229087 1E-08 2,39E-06 0,1648506 3,93354E-07
1030 71959887 0,218776 1E-08 2,59E-06 0,1574311 4,07812E-07
1040 71959887 0,20893 1E-08 2,06E-06 0,1503455 3,09213E-07
1050 71959887 0,199526 1E-08 2,22E-06 0,1435789 3,18495E-07
1060 71959887 0,2 1E-08 1,75E-06 0,1439198 2,51218E-07
1070 71959887 0,2 1E-08 1,82E-06 0,1439198 2,62276E-07
1080 71959887 0,2 1E-08 1,69E-06 0,1439198 2,42854E-07
1090 71959887 0,2 1E-08 1,27E-06 0,1439198 1,82441E-07
1100 71959887 0,2 1E-08 1,25E-06 0,1439198 1,80569E-07
1110 71959887 0,2 1E-08 1,21E-06 0,1439198 1,73974E-07
1120 71959887 0,2 1E-08 1,39E-06 0,1439198 2,00434E-07
1130 71959887 0,2 1E-08 8,89E-07 0,1439198 1,28003E-07
1140 71959887 0,2 1E-08 1,05E-06 0,1439198 1,50452E-07
1150 71959887 0,2 1E-08 7,3E-07 0,1439198 1,05013E-07
1160 71959887 0,126191 1E-08 1,01E-06 0,0908072 9,16117E-08
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1170 71959887 0,079621 1E-08 6,02E-07 0,0572955 3,44689E-08
1180 71959887 0,050238 1E-08 7,76E-07 0,036151 2,80628E-08
1190 71959887 0,031698 1E-08 5,2E-07 0,0228097 1,18633E-08
1200 71959887 0,02 1E-08 5,17E-07 0,014392 7,44696E-09
1210 71959887 0,02 1E-08 5,16E-07 0,014392 7,42675E-09
1220 71959887 0,02 1E-08 7,22E-07 0,014392 1,039E-08
1230 71959887 0,02 1E-08 6,31E-07 0,014392 9,07978E-09
1240 71959887 0,02 1E-08 4,5E-07 0,014392 6,47369E-09
1250 71959887 0,02 1E-08 2,37E-07 0,014392 3,4168E-09
1260 71959887 0,02 1E-08 3,83E-07 0,014392 5,5167E-09
1270 71959887 0,02 1E-08 1,61E-07 0,014392 2,31229E-09
1280 71959887 0,02 1E-08 1,62E-07 0,014392 2,33619E-09
1290 71959887 0,02 1E-08 4,28E-07 0,014392 6,16138E-09
1300 71959887 0,02 1E-08 3,2E-07 0,014392 4,60895E-09
1310 71959887 0,02 1E-08 3,73E-07 0,014392 5,37092E-09
1320 71959887 0,02 1E-08 3,24E-07 0,014392 4,65706E-09
1330 71959887 0,02 1E-08 4,46E-07 0,014392 6,42043E-09
1340 71959887 0,02 1E-08 4,47E-07 0,014392 6,43723E-09
1350 71959887 0,02 1E-08 3,42E-07 0,014392 4,91703E-09
1360 71959887 0,02 1E-08 3,83E-07 0,014392 5,51897E-09
1370 71959887 0,02 1E-08 4,37E-08 0,014392 6,28497E-10
1380 71959887 0,02 1E-08 2,95E-07 0,014392 4,25007E-09
1390 71959887 0,02 1E-08 3,64E-08 0,014392 5,23329E-10
1400 71959887 0,02 1E-08 2,22E-07 0,014392 3,19852E-09
∑( )=75,96 ∑( )=2,12
Table 31 Calculation of PFRTH
λ(nm) L(λ) R(λ) ∆λ L(λ).R(λ).∆λ
380 1,39E+12 0,1 5E-09 6,95E+02
385 1,39E+12 0,13 5E-09 9,03E+02
390 1,39E+12 0,25 5E-09 1,74E+03
395 1,39E+12 0,5 5E-09 3,47E+03
400 1,39E+12 1 5E-09 6,95E+03
405 1,39E+12 2 5E-09 1,39E+04
410 1,39E+12 4 5E-09 2,78E+04
415 1,39E+12 8 5E-09 5,56E+04
420 1,39E+12 9 5E-09 6,25E+04
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425 1,39E+12 9,5 5E-09 6,60E+04
430 1,39E+12 9,8 5E-09 6,81E+04
435 1,39E+12 10 5E-09 6,95E+04
440 1,39E+12 10 5E-09 6,95E+04
445 1,39E+12 9,7 5E-09 6,74E+04
450 1,39E+12 9,4 5E-09 6,53E+04
455 1,39E+12 9 5E-09 6,25E+04
460 1,39E+12 8 5E-09 5,56E+04
465 1,39E+12 7 5E-09 4,86E+04
470 1,39E+12 6,2 5E-09 4,31E+04
475 1,39E+12 5,5 5E-09 3,82E+04
480 1,39E+12 4,5 5E-09 3,13E+04
485 1,39E+12 3,2 5E-09 2,22E+04
490 1,39E+12 2,2 5E-09 1,53E+04
495 1,39E+12 1,6 5E-09 1,11E+04
500 1,39E+12 1 5E-09 6,95E+03
505 1,39E+12 1 5E-09 6,95E+03
510 1,39E+12 1 5E-09 6,95E+03
515 1,39E+12 1 5E-09 6,95E+03
520 1,39E+12 1 5E-09 6,95E+03
525 1,39E+12 1 5E-09 6,95E+03
530 1,39E+12 1 5E-09 6,95E+03
535 1,39E+12 1 5E-09 6,95E+03
540 1,39E+12 1 5E-09 6,95E+03
545 1,39E+12 1 5E-09 6,95E+03
550 1,39E+12 1 5E-09 6,95E+03
555 1,39E+12 1 5E-09 6,95E+03
560 1,39E+12 1 5E-09 6,95E+03
565 1,39E+12 1 5E-09 6,95E+03
570 1,39E+12 1 5E-09 6,95E+03
575 1,39E+12 1 5E-09 6,95E+03
580 1,39E+12 1 5E-09 6,95E+03
585 1,39E+12 1 5E-09 6,95E+03
590 1,39E+12 1 5E-09 6,95E+03
595 1,39E+12 1 5E-09 6,95E+03
600 1,39E+12 1 5E-09 6,95E+03
605 1,39E+12 1 5E-09 6,95E+03
610 1,39E+12 1 5E-09 6,95E+03
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615 1,39E+12 1 5E-09 6,95E+03
620 1,39E+12 1 5E-09 6,95E+03
625 1,39E+12 1 5E-09 6,95E+03
630 1,39E+12 1 5E-09 6,95E+03
635 1,39E+12 1 5E-09 6,95E+03
640 1,39E+12 1 5E-09 6,95E+03
645 1,39E+12 1 5E-09 6,95E+03
650 1,39E+12 1 5E-09 6,95E+03
655 1,39E+12 1 5E-09 6,95E+03
660 1,39E+12 1 5E-09 6,95E+03
665 1,39E+12 1 5E-09 6,95E+03
670 1,39E+12 1 5E-09 6,95E+03
675 1,39E+12 1 5E-09 6,95E+03
680 1,39E+12 1 5E-09 6,95E+03
685 1,39E+12 1 5E-09 6,95E+03
690 1,39E+12 1 5E-09 6,95E+03
695 1,39E+12 1 5E-09 6,95E+03
700 1,39E+12 1 5E-09 6,95E+03
705 1,39E+12 0,977237 5E-09 6,79E+03
710 1,39E+12 0,954993 5E-09 6,63E+03
715 1,39E+12 0,933254 5E-09 6,48E+03
720 1,39E+12 0,912011 5E-09 6,33E+03
725 1,39E+12 0,891251 5E-09 6,19E+03
730 1,39E+12 0,870964 5E-09 6,05E+03
735 1,39E+12 0,851138 5E-09 5,91E+03
740 1,39E+12 0,831764 5E-09 5,78E+03
745 1,39E+12 0,812831 5E-09 5,65E+03
750 1,39E+12 0,794328 5E-09 5,52E+03
755 1,39E+12 0,776247 5E-09 5,39E+03
760 1,39E+12 0,758578 5E-09 5,27E+03
765 1,39E+12 0,74131 5E-09 5,15E+03
770 1,39E+12 0,724436 5E-09 5,03E+03
775 1,39E+12 0,707946 5E-09 4,92E+03
780 1,39E+12 0,691831 5E-09 4,81E+03
790 1,39E+12 0,660693 1E-08 9,18E+03
800 1,39E+12 0,630957 1E-08 8,77E+03
810 1,39E+12 0,60256 1E-08 8,37E+03
820 1,39E+12 0,57544 1E-08 7,99E+03
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830 1,39E+12 0,549541 1E-08 7,63E+03
840 1,39E+12 0,524807 1E-08 7,29E+03
850 1,39E+12 0,501187 1E-08 6,96E+03
860 1,39E+12 0,47863 1E-08 6,65E+03
870 1,39E+12 0,457088 1E-08 6,35E+03
880 1,39E+12 0,436516 1E-08 6,06E+03
890 1,39E+12 0,416869 1E-08 5,79E+03
900 1,39E+12 0,398107 1E-08 5,53E+03
910 1,39E+12 0,380189 1E-08 5,28E+03
920 1,39E+12 0,363078 1E-08 5,04E+03
930 1,39E+12 0,346737 1E-08 4,82E+03
940 1,39E+12 0,331131 1E-08 4,60E+03
950 1,39E+12 0,316228 1E-08 4,39E+03
960 1,39E+12 0,301995 1E-08 4,20E+03
970 1,39E+12 0,288403 1E-08 4,01E+03
980 1,39E+12 0,275423 1E-08 3,83E+03
990 1,39E+12 0,263027 1E-08 3,65E+03
1000 1,39E+12 0,251189 1E-08 3,49E+03
1010 1,39E+12 0,239883 1E-08 3,33E+03
1020 1,39E+12 0,229087 1E-08 3,18E+03
1030 1,39E+12 0,218776 1E-08 3,04E+03
1040 1,39E+12 0,20893 1E-08 2,90E+03
1050 1,39E+12 0,199526 1E-08 2,77E+03
1060 1,39E+12 0,2 1E-08 2,78E+03
1070 1,39E+12 0,2 1E-08 2,78E+03
1080 1,39E+12 0,2 1E-08 2,78E+03
1090 1,39E+12 0,2 1E-08 2,78E+03
1100 1,39E+12 0,2 1E-08 2,78E+03
1110 1,39E+12 0,2 1E-08 2,78E+03
1120 1,39E+12 0,2 1E-08 2,78E+03
1130 1,39E+12 0,2 1E-08 2,78E+03
1140 1,39E+12 0,2 1E-08 2,78E+03
1150 1,39E+12 0,2 1E-08 2,78E+03
1160 1,39E+12 0,126191 1E-08 1,75E+03
1170 1,39E+12 0,079621 1E-08 1,11E+03
1180 1,39E+12 0,050238 1E-08 6,98E+02
1190 1,39E+12 0,031698 1E-08 4,40E+02
1200 1,39E+12 0,02 1E-08 2,78E+02
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1210 1,39E+12 0,02 1E-08 2,78E+02
1220 1,39E+12 0,02 1E-08 2,78E+02
1230 1,39E+12 0,02 1E-08 2,78E+02
1240 1,39E+12 0,02 1E-08 2,78E+02
1250 1,39E+12 0,02 1E-08 2,78E+02
1260 1,39E+12 0,02 1E-08 2,78E+02
1270 1,39E+12 0,02 1E-08 2,78E+02
1280 1,39E+12 0,02 1E-08 2,78E+02
1290 1,39E+12 0,02 1E-08 2,78E+02
1300 1,39E+12 0,02 1E-08 2,78E+02
1310 1,39E+12 0,02 1E-08 2,78E+02
1320 1,39E+12 0,02 1E-08 2,78E+02
1330 1,39E+12 0,02 1E-08 2,78E+02
1340 1,39E+12 0,02 1E-08 2,78E+02
1350 1,39E+12 0,02 1E-08 2,78E+02
1360 1,39E+12 0,02 1E-08 2,78E+02
1370 1,39E+12 0,02 1E-08 2,78E+02
1380 1,39E+12 0,02 1E-08 2,78E+02
1390 1,39E+12 0,02 1E-08 2,78E+02
1400 1,39E+12 0,02 1E-08 2,78E+02
∑( )=1,47E+6
Table 32 Calculation of LR
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Appendix A Data Sheet
The tables below show the spectral irradiance date En(λ) which was used in determining the
shades and their characteristics. Where n = shade number and λ = wavelngth in nano metres
λ(nm) E1,3(λ) E1,5(λ) E1,7(λ) E2(λ) E2,5(λ) E3(λ) E4(λ) E5(λ)
300 26,96165 32,66086 40,09267 53,85102 88,09837 144,5067 387,7689 1040,748
305 26,96165 32,66086 40,09267 53,85102 88,09837 144,5067 387,7689 1040,748
310 26,96165 32,66086 40,09267 53,85102 88,09837 144,5067 387,7689 1040,748
315 26,96165 32,66086 40,09267 53,85102 88,09837 144,5067 387,7689 1040,748
320 26,96165 32,66086 40,09267 53,85102 88,09837 144,5067 387,7689 1040,748
325 26,96165 32,66086 40,09267 53,85102 88,09837 144,5067 387,7689 1040,748
330 26,96165 32,66086 40,09267 53,85102 88,09837 144,5067 387,7689 1040,748
335 26,96165 32,66086 40,09267 53,85102 88,09837 144,5067 387,7689 1040,748
340 26,96165 32,66086 40,09267 53,85102 88,09837 144,5067 387,7689 1040,748
345 138,1902 167,4011 205,4924 276,0099 451,5425 740,6597 1987,485 5334,285
350 249,4187 302,1414 370,8922 498,1688 814,9867 1336,813 3587,2 9627,822
355 360,6473 436,8817 536,2919 720,3277 1178,431 1932,966 5186,916 13921,36
360 471,8758 571,622 701,6916 942,4866 1541,875 2529,119 6786,631 18214,9
365 583,1044 706,3622 867,0914 1164,646 1905,319 3125,272 8386,347 22508,43
370 694,3329 841,1025 1032,491 1386,804 2268,763 3721,425 9986,063 26801,97
375 805,5615 975,8428 1197,891 1608,963 2632,208 4317,578 11585,78 31095,51
380 920,6417 1115,249 1369,018 1838,815 3008,237 4934,375 13240,89 35537,72
385 1023,979 1240,43 1522,683 2045,213 3345,896 5488,233 14727,11 39526,65
390 1135,771 1375,853 1688,921 2268,498 3711,182 6087,407 16334,93 43841,95
395 1254,139 1519,242 1864,938 2504,917 4097,956 6721,827 18037,33 48411,08
400 1381,902 1674,011 2054,924 2760,099 4515,425 7406,597 19874,85 53342,85
405 1517,18 1837,885 2256,086 3030,292 4957,452 8131,648 21820,45 58564,72
410 1660,913 2012 2469,82 3317,373 5427,105 8902,015 23887,65 64112,96
415 1812,161 2195,22 2694,731 3619,464 5921,316 9712,662 26062,93 69951,3
420 1971,864 2388,681 2932,213 3938,442 6443,153 10568,62 28359,82 76116
425 2140,962 2593,523 3183,666 4276,184 6995,686 11474,94 30791,82 82643,34
430 2317,575 2807,468 3446,294 4628,936 7572,777 12421,53 33331,91 89460,78
435 2502,642 3031,656 3721,494 4998,575 8177,494 13413,44 35993,6 96604,59
440 2696,165 3266,086 4009,267 5385,102 8809,837 14450,67 38776,89 104074,8
445 2898,143 3510,758 4309,613 5788,515 9469,808 15533,21 41681,78 111871,3
450 3108,575 3765,672 4622,532 6208,816 10157,4 16661,07 44708,27 119994,2
455 3326,523 4029,69 4946,626 6644,127 10869,56 17829,2 47842,85 128407,2
460 3551,986 4302,812 5281,895 7094,449 11606,27 19037,62 51085,51 137110,3
465 3785,904 4586,177 5629,738 7561,658 12370,61 20291,36 54449,78 146139,8
470 4027,338 4878,645 5988,756 8043,878 13159,5 21585,37 57922,14 155459,4
475 4276,287 5180,217 6358,949 8541,109 13972,95 22919,67 61502,58 165069,1
480 4531,812 5489,756 6738,922 9051,474 14807,89 24289,21 65177,6 174932,6
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485 4794,852 5808,398 7130,07 9576,85 15667,39 25699,03 68960,71 185086,3
490 5064,469 6135,007 7530,997 10115,36 16548,37 27144,1 72838,4 195493,7
495 5340,661 6469,582 7941,702 10667 17450,85 28624,41 76810,67 206155,1
500 5623,43 6812,122 8362,186 11231,78 18374,8 30139,97 80877,51 217070,2
505 5911,835 7161,491 8791,052 11807,82 19317,18 31685,73 85025,43 228203
510 6205,877 7517,688 9228,3 12395,12 20277,97 33261,71 89254,4 239553,3
515 6505,555 7880,713 9673,929 12993,67 21257,19 34867,9 93564,45 251121,2
520 6810,87 8250,566 10127,94 13603,48 22254,82 36504,3 97955,56 262906,6
525 7119,942 8624,971 10587,54 14220,8 23264,72 38160,84 102400,7 274837,2
530 7433,712 9005,066 11054,12 14847,49 24289,98 39842,56 106913,4 286949
535 7752,179 9390,851 11527,69 15483,57 25330,58 41549,45 111493,7 299242,1
540 8074,404 9781,188 12006,85 16127,16 26383,47 43276,48 116128 311680,3
545 8399,446 10174,94 12490,19 16776,37 27445,56 45018,62 120802,8 324227,3
550 8728,247 10573,24 12979,13 17433,09 28519,93 46780,89 125531,7 336919,4
555 9059,866 10974,96 13472,26 18095,44 29603,51 48558,27 130301,2 349720,2
560 9394,303 11380,09 13969,57 18763,42 30696,3 50350,76 135111,1 362629,8
565 9730,619 11787,5 14469,68 19435,15 31795,23 52153,32 139948,1 375612
570 10068,81 12197,18 14972,59 20110,63 32900,29 53965,95 144812,1 388666,7
575 10408,89 12609,14 15478,29 20789,87 34011,5 55788,64 149703,1 401793,9
580 10750,84 13023,38 15986,78 21472,86 35128,84 57621,41 154621,2 414993,6
585 11092,79 13437,61 16495,27 22155,85 36246,19 59454,18 159539,2 428193,3
590 11435,69 13852,98 17005,16 22840,71 37366,6 61291,98 164470,8 441429,3
595 11779,52 14269,5 17516,45 23527,45 38490,09 63134,82 169415,8 454701,6
600 12122,41 14684,87 18026,34 24212,32 39610,5 64972,62 174347,4 467937,5
605 12466,24 15101,38 18537,62 24899,06 40733,99 66815,46 179292,5 481209,8
610 12809,13 15516,75 19047,51 25583,92 41854,4 68653,26 184224 494445,8
615 13151,08 15930,99 19556 26266,91 42971,75 70486,03 189142,1 507645,5
620 13492,1 16344,09 20063,1 26948,02 44086,02 72313,76 194046,6 520809
625 13832,17 16756,05 20568,8 27627,26 45197,23 74136,46 198937,6 533936,2
630 14170,37 17165,73 21071,7 28302,74 46302,3 75949,09 203801,6 546990,8
635 14506,68 17573,14 21571,81 28974,47 47401,22 77751,65 208638,6 559973
640 14841,12 17978,27 22069,13 29642,45 48494,01 79544,13 213448,5 572882,6
645 15173,68 18381,12 22563,65 30306,68 49580,66 81326,55 218231,5 585719,7
650 15503,42 18780,56 23053,99 30965,27 50658,1 83093,86 222973,9 598448
655 15830,34 19176,59 23540,13 31618,24 51726,33 84846,07 227675,7 611067,5
660 16154,44 19569,2 24022,08 32265,58 52785,35 86583,17 232337,1 623578,3
665 16475,73 19958,4 24499,84 32907,29 53835,17 88305,17 236957,9 635980,2
670 16794,2 20344,19 24973,4 33543,37 54875,77 90012,06 241538,1 648273,4
675 17108,9 20725,42 25441,39 34171,94 55904,1 91698,81 246064,4 660421,5
680 17419,86 21102,1 25903,78 34793,01 56920,14 93365,42 250536,5 672424,5
685 17727,05 21474,23 26360,58 35406,57 57923,91 95011,89 254954,7 684282,5
690 18030,49 21841,81 26811,8 36012,63 58915,4 96638,22 259318,8 695995,4
695 18330,16 22204,83 27257,43 36611,19 59894,62 98244,41 263628,8 707563,3
700 18625,15 22562,17 27696,07 37200,36 60858,48 99825,42 267871,3 718949,9
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705 18916,37 22914,95 28129,13 37782,02 61810,06 101386,3 272059,7 730191,4
710 19202,9 23262,04 28555,2 38354,31 62746,3 102922 276180,6 741251,6
715 19484,72 23603,45 28974,29 38917,21 63667,19 104432,5 280234 752130,5
720 19761,86 23939,16 29386,39 39470,73 64572,73 105917,9 284219,7 762828,1
725 20035,23 24270,32 29792,91 40016,75 65465,99 107383,1 288151,5 773380,7
730 20302,97 24594,65 30191,04 40551,5 66340,84 108818,1 292002,1 783715,6
735 20566,01 24913,29 30582,19 41076,88 67200,33 110227,9 295785,3 793869,2
740 20824,35 25226,25 30966,35 41592,87 68044,48 111612,5 299500,8 803841,6
745 21077,06 25532,37 31342,13 42097,61 68870,21 112967 303135,3 813596,3
750 21325,07 25832,81 31710,93 42592,96 69680,6 114296,2 306702,2 823169,7
755 21568,38 26127,55 32072,74 43078,94 70475,63 115600,3 310201,6 832561,8
760 21806,06 26415,47 32426,17 43553,65 71252,25 116874,2 313619,9 841736,4
765 22036,22 26694,28 32768,43 44013,36 72004,31 118107,8 316930,1 850620,8
770 22265,44 26971,95 33109,28 44471,18 72753,29 119336,3 320226,9 859469
775 22485,26 27238,25 33436,17 44910,25 73471,59 120514,5 323388,5 867954,5
780 22704,15 27503,4 33761,66 45347,43 74186,81 121687,7 326536,5 876403,8
790 23121,26 28008,68 34381,91 46180,53 75549,73 123923,3 332535,5 892504,6
800 23563,73 28544,68 35039,88 47064,29 76995,52 126294,8 338899,2 909584,4
810 23890,65 28940,71 35526,02 47717,25 78063,75 128047 343601,1 922203,9
820 24243,88 29368,6 36051,28 48422,76 79217,94 129940,2 348681,3 935838,8
830 24575,5 29770,32 36544,4 49085,11 80301,51 131717,6 353450,7 948639,7
840 24886,45 30147 37006,79 49706,18 81317,56 133384,2 357922,9 960642,7
850 25175,79 30497,51 37437,06 50284,09 82263,01 134935 362084,3 971811,7
860 25445,41 30824,11 37837,98 50822,6 83143,99 136380,1 365962 982219,2
870 25694,36 31125,69 38208,18 51319,83 83957,44 137714,4 369542,4 991828,9
880 25923,58 31403,36 38549,04 51777,66 84706,43 138942,9 372839,1 1000677
890 26133,07 31657,14 38860,56 52196,08 85390,96 140065,7 375852,1 1008764
900 26323,78 31888,15 39144,14 52576,98 86014,1 141087,9 378594,9 1016125
910 26495,69 32096,41 39399,78 52920,35 86575,84 142009,3 381067,4 1022761
920 26649,76 32283,04 39628,88 53228,07 87079,26 142835 383283,2 1028708
930 26785,04 32446,91 39830,05 53498,26 87521,28 143560,1 385228,8 1033930
940 26904,34 32591,44 40007,46 53736,56 87911,13 144199,5 386944,7 1038536
950 27005,8 32714,35 40158,33 53939,2 88242,65 144743,3 388403,9 1042452
960 27092,23 32819,04 40286,85 54111,83 88525,05 145206,6 389646,9 1045788
970 27162,69 32904,39 40391,62 54252,55 88755,27 145584,2 390660,3 1048508
980 27217,18 32970,4 40472,65 54361,38 88933,31 145876,2 391443,9 1050611
990 27257,57 33019,33 40532,71 54442,06 89065,31 146092,7 392024,9 1052170
1000 27283,87 33051,2 40571,83 54494,6 89151,26 146233,7 392403,2 1053186
1010 27297,03 33067,13 40591,39 54520,87 89194,23 146304,2 392592,4 1053694
1020 27297,03 33067,13 40591,39 54520,87 89194,23 146304,2 392592,4 1053694
1030 27283,87 33051,2 40571,83 54494,6 89151,26 146233,7 392403,2 1053186
1040 27259,45 33021,61 40535,51 54445,82 89071,45 146102,8 392051,9 1052243
1050 27222,81 32977,23 40481,03 54372,64 88951,73 145906,4 391525 1050829
1060 27175,84 32920,33 40411,18 54278,82 88798,25 145654,7 390849,4 1049016
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1070 27117,6 32849,77 40324,57 54162,49 88607,93 145342,5 390011,7 1046767
1080 27049,96 32767,83 40223,99 54027,39 88386,92 144980 389038,9 1044156
1090 26972,92 32674,52 40109,44 53873,53 88135,21 144567,1 387931 1041183
1100 26886,5 32569,82 39980,92 53700,91 87852,8 144103,9 386688 1037847
1110 26790,67 32453,74 39838,43 53509,52 87539,7 143590,3 385309,9 1034148
1120 26687,34 32328,56 39684,76 53303,13 87202,04 143036,4 383823,7 1030159
1130 26576,48 32194,28 39519,92 53081,72 86839,83 142442,3 382229,3 1025880
1140 26458,12 32050,89 39343,9 52845,3 86453,05 141807,9 380526,9 1021311
1150 26332,23 31898,39 39156,71 52593,87 86041,72 141133,2 378716,5 1016451
1160 26199,77 31737,94 38959,74 52329,3 85608,9 140423,2 376811,4 1011338
1170 26061,68 31570,65 38754,39 52053,48 85157,67 139683,1 374825,3 1006008
1180 25917,94 31396,53 38540,65 51766,4 84688,02 138912,7 372758,1 1000459
1190 25767,63 31214,45 38317,14 51466,19 84196,87 138107,1 370596,3 994657,4
1200 25612,63 31026,68 38086,64 51156,59 83690,39 137276,3 368366,9 988674
1210 25452,92 30833,22 37849,16 50837,61 83168,55 136420,4 366070,1 982509,3
1220 25289,46 30635,2 37606,09 50511,13 82634,43 135544,3 363719,1 976199,5
1230 25120,37 30430,36 37354,64 50173,39 82081,9 134637,9 361287,1 969672,2
1240 24948,45 30222,11 37098,99 49830,02 81520,16 133716,5 358814,6 963036,1
1250 24772,78 30009,3 36837,76 49479,14 80946,14 132775 356288 956254,9
1260 24593,35 29791,94 36570,94 49120,76 80359,84 131813,3 353707,4 949328,7
1270 24409,22 29568,89 36297,14 48753 79758,19 130826,4 351059,2 942221,1
1280 24226,03 29346,98 36024,73 48387,11 79159,61 129844,5 348424,5 935149,8
1290 24038,14 29119,38 35745,34 48011,84 78545,69 128837,5 345722,3 927897,2
1300 23848,38 28889,5 35463,16 47632,82 77925,62 127820,4 342993,1 920572,1
1310 23655,79 28656,21 35176,78 47248,17 77296,35 126788,3 340223,3 913138,2
1320 23461,33 28420,64 34887,61 46859,77 76660,93 125746 337426,5 905631,8
1330 23265,93 28183,93 34597,04 46469,49 76022,45 124698,7 334616,2 898089,1
1340 23068,65 27944,95 34303,68 46075,46 75377,83 123641,3 331778,9 890473,8
1350 22870,43 27704,83 34008,92 45679,55 74730,14 122578,9 328928 882822,3
1360 22670,33 27462,44 33711,37 45279,89 74076,31 121506,5 326050,1 875098,3
1370 22469,29 27218,9 33412,42 44878,35 73419,4 120429 323158,8 867338
1380 22268,26 26975,37 33113,47 44476,81 72762,5 119351,4 320267,4 859577,8
1390 22065,34 26729,56 32811,73 44071,52 72099,46 118263,9 317349 851745
1400 21862,42 26483,75 32509,99 43666,23 71436,42 117176,3 314430,6 843912,2
λ(nm) E6(λ) E7(λ) E8(λ) E9(λ) E10(λ) E11(λ) E12(λ) E13(λ) E14(λ)
300 2789,782 7439,418 20086,43 54287,65 144506,7 386277,5 1057180 2789782 7439418
305 2789,782 7439,418 20086,43 54287,65 144506,7 386277,5 1057180 2789782 7439418
310 2789,782 7439,418 20086,43 54287,65 144506,7 386277,5 1057180 2789782 7439418
315 2789,782 7439,418 20086,43 54287,65 144506,7 386277,5 1057180 2789782 7439418
320 2789,782 7439,418 20086,43 54287,65 144506,7 386277,5 1057180 2789782 7439418
325 2789,782 7439,418 20086,43 54287,65 144506,7 386277,5 1057180 2789782 7439418
330 2789,782 7439,418 20086,43 54287,65 144506,7 386277,5 1057180 2789782 7439418
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335 2789,782 7439,418 20086,43 54287,65 144506,7 386277,5 1057180 2789782 7439418
340 2789,782 7439,418 20086,43 54287,65 144506,7 386277,5 1057180 2789782 7439418
345 14298,85 38130,26 102951,7 278247,8 740659,7 1979840 5418510 14298847 38130259
350 25807,91 68821,1 185817 502208 1336813 3573403 9779840 25807912 68821099
355 37316,98 99511,94 268682,2 726168,2 1932966 5166966 14141170 37316977 99511940
360 48826,04 130202,8 351547,5 950128,4 2529119 6760529 18502500 48826043 1,3E+08
365 60335,11 160893,6 434412,8 1174089 3125272 8354092 22863830 60335108 1,61E+08
370 71844,17 191584,5 517278 1398049 3721425 9947655 27225160 71844173 1,92E+08
375 83353,24 222275,3 600143,3 1622009 4317578 11541218 31586490 83353238 2,22E+08
380 95260,84 254028,9 685878,1 1853725 4934375 13189963 36098846 95260844 2,54E+08
385 105953,4 282542,4 762864,4 2061796 5488233 14670469 40150757 1,06E+08 2,83E+08
390 117520,8 313388,7 846149,6 2286891 6087407 16272107 44534189 1,18E+08 3,13E+08
395 129768,6 346049,6 934333,9 2525227 6721827 17967960 49175469 1,3E+08 3,46E+08
400 142988,5 381302,6 1029517 2782478 7406597 19798404 54185105 1,43E+08 3,81E+08
405 156986 418629,3 1130299 3054862 8131648 21736521 59489425 1,57E+08 4,19E+08
410 171858,3 458288,9 1237380 3344270 8902015 23795770 65125265 1,72E+08 4,58E+08
415 187508,3 500022,2 1350060 3648811 9712662 25962692 71055790 1,88E+08 5E+08
420 204033,2 544088,5 1469039 3970375 10568625 28250747 77317834 2,04E+08 5,44E+08
425 221530,1 590746,8 1595016 4310855 11474939 30673393 83948235 2,22E+08 5,91E+08
430 239804,6 639478,9 1726593 4666468 12421533 33203713 90873319 2,4E+08 6,39E+08
435 258954 690543,9 1864469 5039104 13413443 35855165 98129924 2,59E+08 6,91E+08
440 278978,2 743941,8 2008643 5428765 14450669 38627749 1,06E+08 2,79E+08 7,44E+08
445 299877,2 799672,7 2159116 5835449 15533210 41521465 1,14E+08 3E+08 8E+08
450 321651,2 857736,4 2315888 6259158 16661067 44536314 1,22E+08 3,22E+08 8,58E+08
455 344202,7 917873,9 2478259 6697999 17829205 47658836 1,3E+08 3,44E+08 9,18E+08
460 367531,9 980085 2646230 7151972 19037623 50889031 1,39E+08 3,68E+08 9,8E+08
465 391735,9 1044629 2820499 7622969 20291357 54240358 1,48E+08 3,92E+08 1,04E+09
470 416717,6 1111247 3000367 8109099 21585371 57699358 1,58E+08 4,17E+08 1,11E+09
475 442476,9 1179938 3185834 8610361 22919667 61266032 1,68E+08 4,42E+08 1,18E+09
480 468916,6 1250444 3376200 9124864 24289207 64926920 1,78E+08 4,69E+08 1,25E+09
485 496134 1323024 3572165 9654500 25699029 68695481 1,88E+08 4,96E+08 1,32E+09
490 524031,8 1397418 3773029 10197376 27144096 72558255 1,99E+08 5,24E+08 1,4E+09
495 552610,1 1473627 3978793 10753494 28624408 76515244 2,09E+08 5,53E+08 1,47E+09
500 581868,8 1551650 4189455 11322852 30139966 80566447 2,2E+08 5,82E+08 1,55E+09
505 611710,7 1631229 4404317 11903560 31685734 84698405 2,32E+08 6,12E+08 1,63E+09
510 642135,8 1712362 4623378 12495617 33261713 88911118 2,43E+08 6,42E+08 1,71E+09
515 673144,2 1795051 4846638 13099023 34867902 93204585 2,55E+08 6,73E+08 1,8E+09
520 704735,8 1879296 5074098 13713778 36504302 97578808 2,67E+08 7,05E+08 1,88E+09
525 736716,3 1964577 5304357 14336100 38160842 1,02E+08 2,79E+08 7,37E+08 1,96E+09
530 769182,7 2051154 5538116 14967880 39842558 1,07E+08 2,91E+08 7,69E+08 2,05E+09
535 802135,2 2139027 5775373 15609117 41549448 1,11E+08 3,04E+08 8,02E+08 2,14E+09
540 835476,5 2227937 6015431 16257921 43276480 1,16E+08 3,17E+08 8,35E+08 2,23E+09
545 869109,4 2317625 6257588 16912399 45018616 1,2E+08 3,29E+08 8,69E+08 2,32E+09
550 903131,1 2408350 6502544 17574443 46780893 1,25E+08 3,42E+08 9,03E+08 2,41E+09
Determination of Retinal Thermal Hazard and Blue Light Photochemical Hazard Protection Needed by
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555 937444,5 2499852 6749600 18242163 48558274 1,3E+08 3,55E+08 9,37E+08 2,5E+09
560 972049,4 2592132 6998756 18915556 50350762 1,35E+08 3,68E+08 9,72E+08 2,59E+09
565 1006849 2684930 7249311 19592733 52153319 1,39E+08 3,82E+08 1,01E+09 2,68E+09
570 1041843 2778247 7501267 20273693 53965946 1,44E+08 3,95E+08 1,04E+09 2,78E+09
575 1077031 2872082 7754621 20958436 55788644 1,49E+08 4,08E+08 1,08E+09 2,87E+09
580 1112413 2966436 8009376 21646963 57621412 1,54E+08 4,22E+08 1,11E+09 2,97E+09
585 1147796 3060789 8264131 22335489 59454179 1,59E+08 4,35E+08 1,15E+09 3,06E+09
590 1183276 3155402 8519586 23025907 61291982 1,64E+08 4,48E+08 1,18E+09 3,16E+09
595 1218853 3250274 8775740 23718216 63134820 1,69E+08 4,62E+08 1,22E+09 3,25E+09
600 1254333 3344887 9031195 24408634 64972623 1,74E+08 4,75E+08 1,25E+09 3,34E+09
605 1289910 3439759 9287349 25100943 66815461 1,79E+08 4,89E+08 1,29E+09 3,44E+09
610 1325389 3534372 9542804 25791361 68653263 1,84E+08 5,02E+08 1,33E+09 3,53E+09
615 1360772 3628725 9797558 26479887 70486031 1,88E+08 5,16E+08 1,36E+09 3,63E+09
620 1396057 3722820 10051613 27166522 72313764 1,93E+08 5,29E+08 1,4E+09 3,72E+09
625 1431246 3816655 10304968 27851265 74136461 1,98E+08 5,42E+08 1,43E+09 3,82E+09
630 1466239 3909972 10556923 28532225 75949089 2,03E+08 5,56E+08 1,47E+09 3,91E+09
635 1501039 4002770 10807479 29209402 77751646 2,08E+08 5,69E+08 1,5E+09 4E+09
640 1535644 4095050 11056634 29882796 79544133 2,13E+08 5,82E+08 1,54E+09 4,1E+09
645 1570054 4186811 11304390 30552407 81326550 2,17E+08 5,95E+08 1,57E+09 4,19E+09
650 1604173 4277795 11550047 31216343 83093862 2,22E+08 6,08E+08 1,6E+09 4,28E+09
655 1638000 4368001 11793603 31874604 84846068 2,27E+08 6,21E+08 1,64E+09 4,37E+09
660 1671536 4457430 12035061 32527191 86583170 2,31E+08 6,33E+08 1,67E+09 4,46E+09
665 1704780 4546081 12274418 33174103 88305166 2,36E+08 6,46E+08 1,7E+09 4,55E+09
670 1737733 4633954 12511676 33815340 90012056 2,41E+08 6,59E+08 1,74E+09 4,63E+09
675 1770296 4720790 12746134 34449011 91698807 2,45E+08 6,71E+08 1,77E+09 4,72E+09
680 1802471 4806590 12977793 35075116 93365417 2,5E+08 6,83E+08 1,8E+09 4,81E+09
685 1834257 4891353 13206652 35693655 95011887 2,54E+08 6,95E+08 1,83E+09 4,89E+09
690 1865654 4975079 13432712 36304627 96638217 2,58E+08 7,07E+08 1,87E+09 4,98E+09
695 1896663 5057768 13655972 36908034 98244406 2,63E+08 7,19E+08 1,9E+09 5,06E+09
700 1927185 5139161 13875733 37501982 99825420 2,67E+08 7,3E+08 1,93E+09 5,14E+09
705 1957319 5219517 14092695 38088364 1,01E+08 2,71E+08 7,42E+08 1,96E+09 5,22E+09
710 1986966 5298577 14306157 38665289 1,03E+08 2,75E+08 7,53E+08 1,99E+09 5,3E+09
715 2016128 5376341 14516120 39232755 1,04E+08 2,79E+08 7,64E+08 2,02E+09 5,38E+09
720 2044803 5452808 14722583 39790764 1,06E+08 2,83E+08 7,75E+08 2,04E+09 5,45E+09
725 2073090 5528239 14926247 40341207 1,07E+08 2,87E+08 7,86E+08 2,07E+09 5,53E+09
730 2100793 5602115 15125711 40880300 1,09E+08 2,91E+08 7,96E+08 2,1E+09 5,6E+09
735 2128011 5674695 15321676 41409936 1,1E+08 2,95E+08 8,06E+08 2,13E+09 5,67E+09
740 2154742 5745979 15514142 41930114 1,12E+08 2,98E+08 8,17E+08 2,15E+09 5,75E+09
745 2180890 5815707 15702409 42438942 1,13E+08 3,02E+08 8,26E+08 2,18E+09 5,82E+09
750 2206552 5884139 15887176 42938313 1,14E+08 3,06E+08 8,36E+08 2,21E+09 5,88E+09
755 2231728 5951275 16068444 43428226 1,16E+08 3,09E+08 8,46E+08 2,23E+09 5,95E+09
760 2256321 6016856 16245512 43906789 1,17E+08 3,12E+08 8,55E+08 2,26E+09 6,02E+09
765 2280136 6080364 16416982 44370221 1,18E+08 3,16E+08 8,64E+08 2,28E+09 6,08E+09
770 2303854 6143612 16587751 44831760 1,19E+08 3,19E+08 8,73E+08 2,3E+09 6,14E+09
Determination of Retinal Thermal Hazard and Blue Light Photochemical Hazard Protection Needed by
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775 2326600 6204267 16751522 45274384 1,21E+08 3,22E+08 8,82E+08 2,33E+09 6,2E+09
780 2349249 6264664 16914593 45715117 1,22E+08 3,25E+08 8,9E+08 2,35E+09 6,26E+09
790 2392408 6379755 17225338 46554967 1,24E+08 3,31E+08 9,07E+08 2,39E+09 6,38E+09
800 2438192 6501844 17554979 47445890 1,26E+08 3,38E+08 9,24E+08 2,44E+09 6,5E+09
810 2472019 6592050 17798536 48104151 1,28E+08 3,42E+08 9,37E+08 2,47E+09 6,59E+09
820 2508568 6689515 18061689 48815376 1,3E+08 3,47E+08 9,51E+08 2,51E+09 6,69E+09
830 2542881 6781017 18308745 49483095 1,32E+08 3,52E+08 9,64E+08 2,54E+09 6,78E+09
840 2575056 6866816 18540404 50109200 1,33E+08 3,57E+08 9,76E+08 2,58E+09 6,87E+09
850 2604995 6946654 18755966 50691799 1,35E+08 3,61E+08 9,87E+08 2,6E+09 6,95E+09
860 2632893 7021048 18956830 51234676 1,36E+08 3,65E+08 9,98E+08 2,63E+09 7,02E+09
870 2658652 7089740 19142297 51735938 1,38E+08 3,68E+08 1,01E+09 2,66E+09 7,09E+09
880 2682370 7152988 19313067 52197478 1,39E+08 3,71E+08 1,02E+09 2,68E+09 7,15E+09
890 2704047 7210792 19469139 52619295 1,4E+08 3,74E+08 1,02E+09 2,7E+09 7,21E+09
900 2723780 7263413 19611214 53003280 1,41E+08 3,77E+08 1,03E+09 2,72E+09 7,26E+09
910 2741568 7310849 19739291 53349435 1,42E+08 3,8E+08 1,04E+09 2,74E+09 7,31E+09
920 2757510 7353359 19854071 53659650 1,43E+08 3,82E+08 1,04E+09 2,76E+09 7,35E+09
930 2771507 7390686 19954853 53932034 1,44E+08 3,84E+08 1,05E+09 2,77E+09 7,39E+09
940 2783852 7423606 20043737 54172262 1,44E+08 3,85E+08 1,05E+09 2,78E+09 7,42E+09
950 2794350 7451601 20119323 54376550 1,45E+08 3,87E+08 1,06E+09 2,79E+09 7,45E+09
960 2803293 7475449 20183712 54550573 1,45E+08 3,88E+08 1,06E+09 2,8E+09 7,48E+09
970 2810584 7494890 20236203 54692440 1,46E+08 3,89E+08 1,07E+09 2,81E+09 7,49E+09
980 2816222 7509924 20276795 54802150 1,46E+08 3,9E+08 1,07E+09 2,82E+09 7,51E+09
990 2820401 7521070 20306890 54883487 1,46E+08 3,91E+08 1,07E+09 2,82E+09 7,52E+09
1000 2823123 7528328 20326487 54936450 1,46E+08 3,91E+08 1,07E+09 2,82E+09 7,53E+09
1010 2824484 7531957 20336285 54962932 1,46E+08 3,91E+08 1,07E+09 2,82E+09 7,53E+09
1020 2824484 7531957 20336285 54962932 1,46E+08 3,91E+08 1,07E+09 2,82E+09 7,53E+09
1030 2823123 7528328 20326487 54936450 1,46E+08 3,91E+08 1,07E+09 2,82E+09 7,53E+09
1040 2820596 7521589 20308290 54887270 1,46E+08 3,91E+08 1,07E+09 2,82E+09 7,52E+09
1050 2816805 7511480 20280995 54813499 1,46E+08 3,9E+08 1,07E+09 2,82E+09 7,51E+09
1060 2811945 7498519 20246001 54718921 1,46E+08 3,89E+08 1,07E+09 2,81E+09 7,5E+09
1070 2805918 7482448 20202609 54601645 1,45E+08 3,89E+08 1,06E+09 2,81E+09 7,48E+09
1080 2798919 7463784 20152218 54465453 1,45E+08 3,88E+08 1,06E+09 2,8E+09 7,46E+09
1090 2790948 7442529 20094828 54310345 1,45E+08 3,86E+08 1,06E+09 2,79E+09 7,44E+09
1100 2782005 7418681 20030439 54136322 1,44E+08 3,85E+08 1,05E+09 2,78E+09 7,42E+09
1110 2772091 7392241 19959052 53943384 1,44E+08 3,84E+08 1,05E+09 2,77E+09 7,39E+09
1120 2761398 7363728 19882066 53735313 1,43E+08 3,82E+08 1,05E+09 2,76E+09 7,36E+09
1130 2749928 7333141 19799480 53512109 1,42E+08 3,81E+08 1,04E+09 2,75E+09 7,33E+09
1140 2737680 7300480 19711296 53273773 1,42E+08 3,79E+08 1,04E+09 2,74E+09 7,3E+09
1150 2724655 7265745 19617513 53020304 1,41E+08 3,77E+08 1,03E+09 2,72E+09 7,27E+09
1160 2710949 7229196 19518830 52753595 1,4E+08 3,75E+08 1,03E+09 2,71E+09 7,23E+09
1170 2696660 7191092 19415948 52475536 1,4E+08 3,73E+08 1,02E+09 2,7E+09 7,19E+09
1180 2681787 7151432 19308868 52186128 1,39E+08 3,71E+08 1,02E+09 2,68E+09 7,15E+09
1190 2666234 7109958 19196887 51883480 1,38E+08 3,69E+08 1,01E+09 2,67E+09 7,11E+09
1200 2650196 7067188 19081408 51571373 1,37E+08 3,67E+08 1E+09 2,65E+09 7,07E+09
Determination of Retinal Thermal Hazard and Blue Light Photochemical Hazard Protection Needed by
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1210 2633671 7023122 18962429 51249808 1,36E+08 3,65E+08 9,98E+08 2,63E+09 7,02E+09
1220 2616757 6978019 18840651 50920678 1,36E+08 3,62E+08 9,92E+08 2,62E+09 6,98E+09
1230 2599260 6931360 18714673 50580198 1,35E+08 3,6E+08 9,85E+08 2,6E+09 6,93E+09
1240 2581472 6883924 18586596 50234043 1,34E+08 3,57E+08 9,78E+08 2,58E+09 6,88E+09
1250 2563294 6835452 18455719 49880322 1,33E+08 3,55E+08 9,71E+08 2,56E+09 6,84E+09
1260 2544728 6785942 18322043 49519035 1,32E+08 3,52E+08 9,64E+08 2,54E+09 6,79E+09
1270 2525676 6735136 18184867 49148290 1,31E+08 3,5E+08 9,57E+08 2,53E+09 6,74E+09
1280 2506721 6684589 18048392 48779437 1,3E+08 3,47E+08 9,5E+08 2,51E+09 6,68E+09
1290 2487280 6632747 17908416 48401126 1,29E+08 3,44E+08 9,43E+08 2,49E+09 6,63E+09
1300 2467645 6580386 17767042 48019031 1,28E+08 3,42E+08 9,35E+08 2,47E+09 6,58E+09
1310 2447718 6527247 17623567 47631262 1,27E+08 3,39E+08 9,28E+08 2,45E+09 6,53E+09
1320 2427596 6473590 17478693 47239710 1,26E+08 3,36E+08 9,2E+08 2,43E+09 6,47E+09
1330 2407378 6419674 17333119 46846267 1,25E+08 3,33E+08 9,12E+08 2,41E+09 6,42E+09
1340 2386965 6365239 17186145 46449040 1,24E+08 3,31E+08 9,05E+08 2,39E+09 6,37E+09
1350 2366454 6310545 17038471 46049922 1,23E+08 3,28E+08 8,97E+08 2,37E+09 6,31E+09
1360 2345750 6255332 16889398 45647021 1,22E+08 3,25E+08 8,89E+08 2,35E+09 6,26E+09
1370 2324948 6199861 16739624 45242228 1,2E+08 3,22E+08 8,81E+08 2,32E+09 6,2E+09
1380 2304146 6144389 16589851 44837435 1,19E+08 3,19E+08 8,73E+08 2,3E+09 6,14E+09
1390 2283150 6088399 16438678 44428859 1,18E+08 3,16E+08 8,65E+08 2,28E+09 6,09E+09
1400 2262153 6032409 16287505 44020283 1,17E+08 3,13E+08 8,57E+08 2,26E+09 6,03E+09
Determination of Retinal Thermal Hazard and Blue Light Photochemical Hazard Protection Needed by
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