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DSS-SERIESSolid-State Detectors
Operation ManualPart number J80135 rev. C
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013)
i
DSS Series Solid-State Detectors
Operation Manual
www.HORIBA.com
Rev. C
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013)
ii
Copyright © 2013 HORIBA Instruments Incorporated. All rights reserved. No part of
this document may be reproduced, stored in a retrieval system, or transmitted in any
form by any means, including electronic or mechanical, photocopying and recording
without prior written permission of HORIBA Instruments Incorporated. Requests for
permission should be submitted in writing.
Information in this document is subject to change without notice and does not represent
a commitment on the part of the vendor.
June 2013
Part Number J80135
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013)
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Table of Contents 1 : Introduction ................................................................................................. 1
About the DSS Series Solid-State Detectors .......................................................................................... 1 Disclaimer ............................................................................................................................................... 2 Safety summary ...................................................................................................................................... 4 Risks of ultraviolet exposure ................................................................................................................... 7
2 : Getting Started ............................................................................................. 9 Unpacking and inspection ....................................................................................................................... 9 Components ......................................................................................................................................... 11 Installation of the detector interface ...................................................................................................... 14 Perform x-y alignment on the detector adapter .................................................................................... 18 Mounting the detector in the interface................................................................................................... 20 Connecting the detector ........................................................................................................................ 21 Focusing the detector ........................................................................................................................... 31 Data-acquisition with a DSS detector ................................................................................................... 33 Use of a lock-in amplifier ...................................................................................................................... 35 Transient-decay experiments (time-resolved) with digital storage oscilloscope (DSO) ........................ 39
3 : Signal Optimization ...................................................................................... 41 Introduction ........................................................................................................................................... 41 Optical considerations........................................................................................................................... 41 Thermal considerations ........................................................................................................................ 41 Timing considerations ........................................................................................................................... 42 Electronic considerations ...................................................................................................................... 42
4 : Troubleshooting .......................................................................................... 43 Introduction ........................................................................................................................................... 43 Problems ............................................................................................................................................... 43 Damage threshold and saturation level for detectors ........................................................................... 45
5 : Accessories ................................................................................................ 47
6 : Glossary .................................................................................................... 49
7 : AC (Mains) Power Selection and Fuses ............................................................... 53 Introduction ........................................................................................................................................... 53 To change the fuse ............................................................................................................................... 53
8 : How to Choose a Detector ............................................................................... 55 Introduction ........................................................................................................................................... 55 Some choices ....................................................................................................................................... 55 Wavelength range ................................................................................................................................. 56
9 : Technical Specifications ................................................................................ 59 Specification chart................................................................................................................................. 59 Detector sensitivity curves .................................................................................................................... 60 Liquid-nitrogen-cooled dewar ................................................................................................................ 66 Ambient-temperature detector .............................................................................................................. 68
10 : Service Information ................................................................................. 73 Service policy ........................................................................................................................................ 73 Return authorization .............................................................................................................................. 74 Warranty ............................................................................................................................................... 75
11 : Compliance Information ....................................................................... 77 Declaration of Conformity ..................................................................................................................... 77 Supplementary Information ................................................................................................................... 77
12 : Index .................................................................................................. 79
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013)
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FIGURES
Technical drawing of 1427C Detector Interface .............................................................................. 14
Technical drawing of DSS case. ...................................................................................................... 30
Photograph of data-acquisition with a DSS detector. ...................................................................... 34
Experiment configuration showing photodetector measurement with a chopper and lock-in
amplifier using the Sync Output signal from the chopper controller as a reference signal. ...... 35
Diagram of a transient-decay set-up with digital storage oscilloscope. ........................................... 40
Detector wavelength coverage. ........................................................................................................ 56
Technical drawing of the DSS liquid-nitrogen-cooled dewar. ......................................................... 66
Technical drawing of the ambient-temperature DSS detector. ........................................................ 68
Technical drawing of the two-color DSS detector. .......................................................................... 69
Technical drawing of the DSS-15V-TEP Power Supply. ................................................................ 70
Technical drawing of the DSS-15VP Power Supply. ...................................................................... 71
TABLES
Table I. Individual Components for the DSS Series Detector ........................................................... 9
Table II. Various Accessories for the DSS Series Detector ............................................................. 10
Table III. Accessories available for DSS Detectors ......................................................................... 47
Table IV. Fuses ................................................................................................................................ 53
Table V: Table of Specifications ..................................................................................................... 59
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Introduction
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1: Introduction
About the DSS Series Solid-State Detectors
Solid-state detectors are opto-electronic devices used to
convert photon flux into electronic signals. Available with
wavelength ranges from below 200 nm to beyond 20 µm,
solid-state detectors offer a combination of sensitivity,
dependability, cost, and efficiency not available in other
devices.
HORIBA Scientific recommends that you review the
glossary section. lt contains definitions of terms as used in
this manual. Also included is information about essential
topics relating to detection of spectra.
Note: Keep this and the other reference manuals near the system.
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Introduction
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Disclaimer By setting up or starting to use any HORIBA Instruments Incorporated product, you are
accepting the following terms:
You are responsible for understanding the information contained in this document. You
should not rely on this information as absolute or all-encompassing; there may be local
issues (in your environment) not addressed in this document that you may need to
address, and there may be issues or procedures discussed that may not apply to your
situation.
If you do not follow the instructions or procedures contained in this document, you are
responsible for yourself and your actions and all resulting consequences. If you rely on
the information contained in this document, you are responsible for:
Adhering to safety procedures
Following all precautions
Referring to additional safety documentation, such as Material Safety Data Sheets
(MSDS), when advised
As a condition of purchase, you agree to use safe operating procedures in the use of all
products supplied by HORIBA Instruments Incorporated, including those specified in
the MSDS provided with any chemicals and all warning and cautionary notices, and to
use all safety devices and guards when operating equipment. You agree to indemnify
and hold HORIBA Instruments Incorporated harmless from any liability or obligation
arising from your use or misuse of any such products, including, without limitation, to
persons injured directly or indirectly in connection with your use or operation of the
products. The foregoing indemnification shall in no event be deemed to have expanded
HORIBA Instruments Incorporated’s liability for the products.
HORIBA Instruments Incorporated products are not intended for any general cosmetic,
drug, food, or household application, but may be used for analytical measurements or
research in these fields. A condition of HORIBA Instruments Incorporated’s acceptance
of a purchase order is that only qualified individuals, trained and familiar with
procedures suitable for the products ordered, will handle them. Training and
maintenance procedures may be purchased from HORIBA Instruments Incorporated at
an additional cost. HORIBA Instruments Incorporated cannot be held responsible for
actions your employer or contractor may take without proper training.
Due to HORIBA Instruments Incorporated’s efforts to continuously improve our
products, all specifications, dimensions, internal workings, and operating procedures
are subject to change without notice. All specifications and measurements are
approximate, based on a standard configuration; results may vary with the application
and environment. Any software manufactured by HORIBA Instruments Incorporated is
also under constant development and subject to change without notice.
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Introduction
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Any warranties and remedies with respect to our products are limited to those provided
in writing as to a particular product. In no event shall HORIBA Instruments
Incorporated be held liable for any special, incidental, indirect or consequential
damages of any kind, or any damages whatsoever resulting from loss of use, loss of
data, or loss of profits, arising out of or in connection with our products or the use or
possession thereof. HORIBA Instruments Incorporated is also in no event liable for
damages on any theory of liability arising out of, or in connection with, the use or
performance of our hardware or software, regardless of whether you have been advised
of the possibility of damage.
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Introduction
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Safety summary The following general safety precautions must be observed during all phases of
operation of this instrument. Failure to comply with these precautions or with specific
warnings elsewhere in this manual violates safety standards of design, manufacture and
intended use of instrument. HORIBA Instruments Incorporated assumes no liability for
the customer’s failure to comply with these requirements. Certain symbols are used
throughout the text for special conditions when operating the instruments:
A WARNING notice denotes a hazard. It calls
attention to an operating procedure, practice, or
similar that, if incorrectly performed or adhered to,
could result in personal injury or death. Do not
proceed beyond a WARNING notice until the
indicated conditions are fully understood and met.
HORIBA Instruments Incorporated is not
responsible for damage arising out of improper use
of the equipment.
A CAUTION notice denotes a hazard. It calls
attention to an operating procedure, practice, or
similar that, if incorrectly performed or adhered to,
could result in damage to the product. Do not
proceed beyond a CAUTION notice until the
indicated conditions are fully understood and met.
HORIBA Instruments Incorporated is not
responsible for damage arising out of improper use
of the equipment.
Ultraviolet light! Wear protective goggles, full-
face shield, skin-protection clothing, and UV-
blocking gloves. Do not stare into light.
Intense ultraviolet, visible, or infrared light! Wear
light-protective goggles, full-face shield, skin-
protection clothing, and light-blocking gloves. Do
not stare into light.
Extreme cold! Cryogenic materials must always be
handled with care. Wear protective goggles, full-
face shield, skin-protection clothing, and insulated
gloves. Caution:
Caution:
Caution:
Caution:
Warning:
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Introduction
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Risk of electric shock! This symbol warns the user
that un-insulated voltage within the unit may have
sufficient magnitude to cause electric shock.
Danger to fingers! This symbol warns the user that
the equipment is heavy, and can crush or injure the
hand if precautions are not taken.
This symbol cautions the user that excessive
humidity, if present, can damage certain
equipment.
Hot! This symbol warns the user that hot
equipment may be present, and could create a risk
of fire or burns.
Read this manual before using or servicing the
instrument.
Wear protective gloves.
Wear appropriate safety goggles to protect the
eyes.
Wear an appropriate face-shield to protect the face.
Caution:
Caution:
Caution:
Caution:
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Introduction
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Disconnect instrument from wall outlet (mains)
before servicing.
Earth (ground) terminal; indicates a circuit-
common connected to grounded (earthed) chassis.
Protective earth (ground) terminal.
Alternating current.
On (electrical supply).
Off (electrical supply)
General information is given concerning operation
of the equipment.
Note:
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Introduction
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Risks of ultraviolet exposure
Do not aim the UV light at anyone.
Do not look directly into the light.
Always wear protective goggles, full-face shield and skin protection clothing and
gloves when using the light source.
Light is subdivided into visible light, ranging from 400 nm (violet) to 700 nm (red);
longer infrared, “above red” or > 700 nm, also called heat; and shorter ultraviolet
radiation (UVR), “below violet” or < 400 nm. UVR is further subdivided into UV-
A or near-UV (320–400 nm), also called black (invisible) light; UV-B or mid-UV
(290–320 nm), which is more skin penetrating; and UV-C or far-UV (< 290 nm).
Health effects of exposure to UV light are familiar to anyone who has had sunburn.
However, the UV light level around some UV equipment greatly exceeds the level
found in nature. Acute (short-term) effects include redness or ulceration of the skin.
At high levels of exposure, these burns can be serious. For chronic exposures, there
is also a cumulative risk of harm. This risk depends upon the amount of exposure
during your lifetime. The long-term risks for large cumulative exposure include
premature aging of the skin, wrinkles and, most seriously, skin cancer and cataract.
Damage to vision is likely following exposure to high-intensity UV radiation. In
adults, more than 99% of UV radiation is absorbed by the anterior structures of the
eye. UVR can contribute to the development of age-related cataract, pterygium,
photodermatitis, and cancer of the skin around the eye. It may also contribute to
age-related macular degeneration. Like the skin, the covering of the eye or the
cornea, is epithelial tissue. The danger to the eye is enhanced by the fact that light
Caution: This instrument is used in conjunction with ultraviolet light. Exposure to these radiations, even reflected or diffused, can result in serious, and sometimes irreversible, eye and skin injuries.
Overexposure to ultraviolet rays threatens human health by causing:
Immediate painful sunburn
Skin cancer
Eye damage
Immune-system suppression
Premature aging
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Introduction
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can enter from all angles around the eye and not only in the direction of vision. This
is especially true while working in a dark environment, as the pupil is wide open.
The lens can also be damaged, but because the cornea acts as a filter, the chances
are reduced. This should not lessen the concern over lens damage however, because
cataracts are the direct result of lens damage.
Burns to the eyes are usually more painful and serious than a burn to the skin. Make
sure your eye protection is appropriate for this work. NORMAL EYEGLASSES OR
CONTACTS OFFER VERY LIMITED PROTECTION!
Training
For the use of UV sources, new users must be trained by another member of the
laboratory who, in the opinion of the member of staff in charge of the department, is
sufficiently competent to give instruction on the correct procedure. Newly trained users
should be overseen for some time by a competent person.
Caution: UV exposures are not immediately felt. The user may not realize the hazard until it is too late and the damage is done.
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Getting Started
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2: Getting Started
Unpacking and inspection Carefully unpack your DSS Series detector, examining it for possible shipping damage.
Prior to shipment, your DSS Series detector was inspected and found to be free of
mechanical and electrical defects. Upon acceptance, the carrier assumes responsibility
for its safe arrival. Should you receive this instrument in a damaged condition, apparent
or concealed, it must be noted on the freight bill or express receipt and signed by the
carrier’s agent. Failure to do so could result in the carrier refusing to honor the claim.
Upon filing a claim, notify HORIBA Scientific.
Table I. Individual Components for the DSS Series Detector
Item #
Description Part Number
1 DSS Series Solid-State Detector
with datasheet
DSS-XXX,
varies depending
upon
characteristics
2 Power supply
DSS-15V/TEP,
DSS-15VP
or cable or CCA-LKDSS,
CCA-SQ2DSS
3 Optional optical interface 1427C,
1427C-AU,
FL-1090,
DSS-1679A
4 DSS Series Solid-State Detector Operation Manual J80135
Note: Retain the datasheet—do not discard it.
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Getting Started
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Table II. Various Accessories for the DSS Series Detector
Accessory Part Number Adapters or other parts required
One of these five is required for power: Regulated power supply for DSS ambient and liquid-nitrogen-cooled
systems. ±15V DSS-15VP
Two-channel regulated power supply for DSS ambient and liquid-
nitrogen-cooled systems. ±15V DSS-15VP-2C
Regulated power supply for DSS thermoelectrically cooled systems.
±15V DSS-15V-TEP
Cable, provides ±15V from SpectrAcq2 for DSS detectors. Requires
SpectrAcq2 CCA-SQ2DSS SPECTRACQ2
Cable to power ambient and liquid-nitrogen-cooled DSS detectors
from Stanford Research lock-in amplifiers CCA-LKDSS
(CLI-)SR810,
(CLI-)SR830,
(CLI-)SR510,
(CLI-)SR530
Other optional accessories: Male-to-male gender changer, 9-pin, that allows ambient or liquid-
nitrogen-cooled DSS detectors to obtain the necessary ±15V to power
the preamplifier from an existing DSS-15V-TEP
990078LF DSS-15V-TEP
Allows up to four DSS detectors to share one SpectrAcq2 data-
acquisition module
J23078770 (SW-
DET4) SPECTRACQ2
Enclosed compact chopper to mount onto entrance slit of
monochromator ACH-C J36540 or J35926
Open-head optical chopper ACH-C-OPEN
SpectrAcq2 data-acquisition system with one current-input channel
and one voltage-input channel SPECTRACQ2
Lock-in controller, single-phase, digital, SR810/830 CLI-SR810
CLI-SR830
ACH-C
or ACH-C-OPEN
Adapter to mount DSS silicon detector directly onto MicroHR slit DSS-1679A DSS-S025A or DSS-
S025T
SMA fiber-adapter to SM1-thread for thermoelectrically cooled DSS
detectors DSS-SMA
Housing for DSS detectors with elliptical mirror (6:1) 1427C
Housing for DSS detectors including gold-coated elliptical mirror
(6:1) 1427C-AU
Recommended for
wavelengths above 550
nm
Dual 1427C T adapter with pivoting mirror to allow mounting of two
1427C adapters with two DSS detectors J23078370 1427C × 2
1427C housing for two detectors (two DSS or one DSS and one
PMT) J23079050
1427C-AU with all cables and adapters for Fluorolog®-3
spectrofluorometer FL-1090
DSS detector and
Fluorolog®-3
2⅝″-bore collar for oversized detector housing J36788
Extension collar + three screws for liquid-nitrogen-cooled detector J352179
Additional sleeve for thermolectrically cooled or ambient detector J38268
Additional collar for liquid-nitrogen-cooled detector J36064
A-B switchbox to select between two input signals without
disconnecting cables. Useful for two-color detectors. SWB-AB
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Getting Started
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Components The detector subsystem is generally comprised of three components: an optical
interface, the detector head, and a power supply.
Optical interface
1427C The 1427C detector interface is a housing
with optics, which attaches to the exit slit
of a spectrometer. An elliplical mirror
collects the diverging light from the exit
slit and focuses it onto the active area of
the detector. A six-fold demagnification
concentrates the slit-image area to a smaller image in order to fit within the detector’s
active area. Because a front-surface mirror is used rather than a lens system, the image
position is fixed for the entire range of wavelengths. (Lens systems are prone to a shift
of the focal point caused by chromatic aberration.)
DSS-1679A The DSS-1679A detector adapter is a simple mechanical mount for use with the
MicroHR spectrometer and silicon detector (DSS-S025A or DSS-S025T).
Detector heads
Types of detector heads The two classes of single-channel solid-state detectors that are generally best suited to
spectroscopy are photovoltaics (photodiodes) and photoconductors.
Photodiode detectors generate a voltage or current as a result of absorbing incident
photons. Connecting to support electronics is straightforward, for they often require
only amplification to boost the current or voltage to a level sufficient for accurate
digitization.
Photoconductive detectors change resistance in response to photon flux. These
detectors require a biasing voltage and lock-in amplifier signal-processing to extract the
signal from the inherent noise that is characteristic of this class of detectors.
In either case, the DSS series of detector heads is provided with a built-in preamplifier
to boost the signal to a level of 10 volts, full scale.
How to identify detector heads The DSS series of detectors can be connected to the exit slits of most HORIBA
Scientific spectrometers, including those in spectrofluorometers and Raman
instruments. You can break down the catalog numbers of the detectors to determine the
type of sensor, size of the active area, and cooling technique, if any:
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Getting Started
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The DSS prefix means Detector, Solid-State
Next comes the type designation:
-S refers to a silicon (Si) sensor
-IGA refers to an indium gallium arsenide (InGaAs) sensor
-IA refers to an indium arsenide (InAs) sensor
-IS refers to an indium antimonide (InSb) sensor
-G refers to a germanium (Ge) sensor
-PS refers to a lead sulfide (PbS) sensor
-PSE refers to a lead selenide (PbSe) sensor
-MCT refers to mercury cadmium telluride (HgCdTe)
-S(X) refers to a two-color detector with the silicon in front of the (X) IR
detector
The next three digits refer to the size of the sensor in tenths of a millimeter:
010 denotes a 1.0 mm size
020 denotes a 2.0 mm size
025 denotes a 2.5 mm size
030 denotes a 3.0 mm size
The suffix specifies the detector as cooled or ambient temperature:
A refers to ambient
T refers to thermoelectric cooling
L refers to liquid-nitrogen cooling
Power supplies and interfaces
For ambient and liquid-nitrogen detectors Ambient temperature and liquid-nitrogen-cooled detectors (see A and L suffix above) in
the DSS series require stable ±15 volt power with minimal noise and ripple. This is
normally supplied by the DSS-15VP power supply. The DSS-15VP-2C power supply
provides power to two separate ambient or liquid-nitrogen-cooled DSS detectors.
Power may also be provided through a SpectrAcq2 (with cable CCA-SQ2DSS) or
Stanford Research Systems lock-in amplifier (with cable CCA-LKDSS). For
applications where a lock-in amplifier or other signal-processing is used, these choices
of power supply provide low-noise power to the preamplifier.
For thermoelectrically cooled
detectors The thermoelectrically cooled heads (T suffix)
are provided with the DSS-15V/TEP, which
performs two support functions: low noise
±15 volts DC power for the detector
preamplifier, and thermoelectric cooler drive
to reduce and stabilize the detector’s
temperature.
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Getting Started
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Differences between the power supplies The DSS-15V/TEP controller works with a thermistor integrated into the sensor
mounting cold-plate in the detector head. The temperature is maintained to ±0.2°C
around the set point. The set point of the controller is continuously variable using the
potentiometer on the front panel. The range of temperature settings possible is from
room temperature to –30°C, dependent on the cooler type and heat-sinking. A DC
ammeter is provided for current monitoring along with a green LED temperature status
indicator. The unit has internal current-limiting to protect the cooler from damage.
The DSS-15VP power supply is optionally provided with ambient and liquid-nitrogen-
cooled heads that are used in systems to provide ±15 V power to the detector pre-
amplifier.
Caution: Do not substitute any other power supply for that which is supplied with the instrument. To do so may cause severe damage to the instrument.
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Getting Started
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Installation of the detector interface
Introduction
The 1427C consists of an elliptical
coupling mirror mounted in a housing
that mounts to both the spectrometer exit
slit and the detector head.
The light beam exiting the spectrometer
slit diverges from an image point at the
slit plane. The elliptical mirror is positioned to efficiently collect the light. The 6:1
demagnification ratio of the ellipse reduces the size of the exit-slit image to better fit
the typically small active area of a solid-state detector.
The elliptical mirror is mounted on an internal bracket that provides x and y centering
adjustnents for optimizing the position of the image on the detector. The detector mount
allows vertical translation along the optical axis for positioning the detector at the exit
focus of the 1427C.
The 1427C fits smaller ambient-temperature and thermoelectrically cooled detector
heads as well as the larger, dewar-enclosed liquid-nitrogen-cooled detectors.
Technical drawing of 1427C Detector Interface
Note: Mounting holes designated for “TRIAX” are also used for MicroHR and iHR spectrometers.
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Getting Started
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How to mount the 1427C
Tools required: Allen key set in English units, Phillips and flat-blade screwdrivers, a
visible light source (either a white light or a spectral-line source), clear plastic centering
target (J22644 disc, with J22645 rod, packed with the 1427C.
1 Remove protective cover from the spectrometer’s exit slit.
2 Using a 7⁄64″
Allen key, remove the four cap-head screws from the front part of the 1427C. Remove the the front
part of the 1427C.
3 Place the front part of the 1427C against the entrance-slit housing, so that two mounting holes on the 1427C are aligned with the two holes on the entrance-slit housing. iHR, TRIAX, FHR, and MicroHR
spectrometers use the small holes. M-series spectrometers use the large holes.
4 Using the two mounting screws supplied in the 1427C packaging, mount the front
Spectrometer
DSS detector
1427C
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Getting Started
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part of the 1427C onto the entrance-slit housing. Use M3 screws for iHR and MicroHR. All other spectrometers require
appropriate mounting screws.
5 An optional support leg (with hardware) is provided, if necessary.
a Assemble the leg rods using the 1/4″-20 set
screws provided.
Use a combination of rods that allow support
from the table or other surface under the 1427C
housing.
b Using another 1/4″-20 set screw, attach the
cornpleted leg to the underside of the housing.
c Place the round foot-pad under the leg if you wish.
6 Make sure the sleeve is inserted all the way inside the collar.
The sleeve needs to be left in place for the detector interface alignment, and it
may need to be removed later depending on the type of detector head you have
purchased.
7 Using a 5/64″ Allen key, snug the three no-mar set screws on the collar, to hold the sleeve in place.
Note: It is best to insert the sleeve fully until it bottoms in the collar.
Note: Do not overtighten the three set screws.
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Getting Started
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How to mount the DSS-1679A detector adapter
Introduction The DSS-1679A is a simple mechanical adapter to connect the DSS-XXXXA and T
series ambient and thermoelectrically-cooled heads to the MicroHR spectrometer. This
adapter is only recommended for silicon detectors.
Installation
1 Unscrew the four countersunk screws.
2 Remove the end-plate and height-limiter from the monochromator.
3 Replace the end-plate and height-limiter with the DSS-1679A adapter.
4 Insert the nose of the detector head fully into the adapter.
5 Tighten the set screws.
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Getting Started
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Perform x-y alignment on the detector adapter
1 Direct a bright white light-source into the spectrometer’s entrance.
2 Set the wavelength position on the spectrometer so that you can see visible light at the exit slit. Use 0 nm for the entrance slit and 0.5 nm for the exit slit.
For gratings blazed in the infrared, choose a higher order close to the blaze of
the grating.
For example, a Hg vapor lamp that emits a 546.1 nm line can be used in the
fourth order at 2.1844 µm. For a grating blazed at 2 µm, this will give a brighter
image than tuning to 546.1 nm.
3 Place the clear plastic alignment target into the top opening (J38268 holder sleeve) of the 1427C.
4 While you move the target up and down, you see an image of the slit.
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Getting Started
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5 When you are at the best-focused position, align the image with the center of the target by adjusting the x- and y-position screws at the back of the housing. Do not disturb the corner pivot or the slotted spring-retainer
screw. You must loosen the ⅜″ locknuts on the x- and y-
positioning screws to allow adjustment. Use a 3/32″ Allen
key to adjust. When finished adjusting, snug the locknuts
while holding the set screws with the Allen key to prevent
the adjustment from changing.
6 Close the slits and remove the target for future use.
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Getting Started
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Mounting the detector in the interface
1 If you are mounting a DSS-XXXXL liquid-nitrogen detector head, remove the holder sleeve. For the liquid-nitrogen-cooled heads, the holder sleeve is not required. The
DSS-XXXOL dewar and earlier 1428-series liquid-nitrogen-cooled heads
simply fit into the J36064 standard 29⁄16″ I.D. collar directly.
To remove the sleeve, use a 5/64″ Allen key, loosen the three no-mar set screws
on the collar, and pull the sleeve out of the collar.
2 Place the detector into the 1427C, and tighten the no-mar set screws to secure it in place.
If you are using a liquid-nitrogen (DSS-XXXOL or 1428-series) detector,
HORIBA Scientific recommends purchasing an additional collar (J36064) for
each additional detector head. This allows you to keep the same alignment for
each detector head, and the detectors can be interchanged more easily (with their
collars attached).
For added stability because of the height of the liquid-nitrogen-cooled detectors
(DSS-XXXOL or 1428-series), an extension collar (J352179) is available.
If you are using a thermolectrically cooled or ambient detector, HORIBA
Scientific recommends purchasing an additional sleeve (J38268) for each
additional detector head. This allows you to keep the same alignment for each
detector head, and the detectors can be interchanged more easily (with their
holder sleeves attached).
A 2⅝″-bore collar (Part number J36788) is available for oversize detector
housings (e.g., certain Northcoast dewars).
Note: If more than one detector is sharing the same 1427C, you may have to swap detectors in and our of the detector interface. Swapping detectors requires realigning each detector for optimal performance.
Note: If you are mounting a DSS-XXXXA or -T head, leave the J38268 sleeve in place.
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Connecting the detector
HORIBA Scientific offers two modes of cooling:
Thermoelectric (TE) cooling, operating at –30°C. The TE-cooled detectors are
mounted onto a two-stage Peltier cooling device with an integral heat sink. A
spearate power supply/temperature controller is provide to power and
thermostatically control the detector.
Liquid-nitrogen cooling, operating at –196°C (77 K). These devices are mounted in
a dewar able to hold liquid nitrogen over ten hours.
DSS-XXXA series ambient-temperature detectors
Use the DSS-15VP low-noise power supply or the CCD-
LKDSS cable to draw power from your lock-in amplifier.
The DSS-XXXA is supplied with a short 18″ (46 cm)
power cable wired specifically for the DSS-15VP power
supply.
Note: Before installation, remove from the side of the detector chassis the cap-head ¼″-20 cap-head screw. The purpose of the remaining hole is to mount the detector on a post.
Note: The photosensitive end of the detector is an SM1 thread, useful for mounting purposes.
Caution: Ensure that the beam power on the detector is below the saturation limit. We recommend that you use neutral-density filters to attenuate high levels of optical power. Extremely high beam power can result in damage to the detector.
Caution: Do not connect or disconnect the system cables while any components are powered on. The resulting electrostatic discharge may damage the electronics. Depending upon the system configuration, such electronics may include the detector’s power supply, spectrometer, controller, lock-in amplifier, and host computer.
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If you draw power from your lock-in amplifier: The CCD-LKDSS is designed to draw the appropriate voltages to power the
preamplifier for an ambient or liquid-nitrogen-cooled DSS detector (i.e., not the
thermoelectrically cooled DSS detector) from a lock-in amplifier. It converts a 20 VDC
voltage from the lock-in amplifier to a 15 VDC voltage via a resistive circuit.
Required equipment
Ambient or liquid-nitrogen-cooled DSS detector
Stanford Research lock-in amplifier SR510, SR530, SR810, or SR830
Procedure
1 Connect male 15-pin end of cable J400402 to 15-pin female connector on converter box J400256.
2 Connect 9-pin end of cable to 9-pin preamplifier port on back of lock-in amplifier.
3 Connect cable from DSS detector (9-pin female) to 9-pin end of converter box, to obtain ±15V and ground (earth) required for the DSS detector preamplifier.
CCA-LKDSS connected on left
side to ambient DSS detector, and
on right side to preamp port of
SR510 lock-in amplifier.
If you draw power from the DSS-15V/TEP:
1 Connect the 9-pin D-shell connector to the port on the back of the power supply.
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2 Connect the signal cables to the lock-in amplifier or other signal-processor, according the instructions supplied with the electronics.
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DSS-XXXT series thermoelectrically-cooled detectors
1 Verify that the voltage-selection card is properly oriented for the AC voltage (mains), either 120 V or 240 V. The power-input module is on the rear
panel of the DSS-15V-TEP.
1 Connect the 9-pin male D-shell connector from the DSS-XXXT detector to the DSS-15V-TEP rear-panel. Do not connect the cables
to other connectors.
2 Before switching on the power, rotate the TEMP SET POINT control fully counter-clockwise (25). The front panel of the DSS-
15V-TEP contains the TE-
cooler control
potentiometer, the
temperature STATUS
LEDs (red or green), and
POWER indicator LED.
Note: Before installation, remove from the side of the detector the cap-head ¼″-20 cap-head screw. The remaining hole is used to mount the detector on a post.
Note: The photosensitive end of the detector is an SM1 thread, useful for mounting purposes.
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3 Switch on the POWER switch. The detector pre-amplifier is immediately deactivated. Observe that the
COOLER CURRENT meter drops to near zero, and the green STATUS LED
illuminates.
4 Gradually rotate the TEMP SET POINT knob clockwise to lower the temperature set-point. Rotate the potentiometer gradually, until the COOLER CURRENT meter is in
the proper range (typically 0.5–0.6 A).
5 During the first few days of operation, continue to observe the cooler current occasionally. A gradual increase indicates heating of the cooler assembly (hot plate) in the
detector head. In this case, add additional heat-sinking to the detector housing.
In a normal environment, the 1427C provides ample heat-sinking.
Note: Do not leave the set point in a position where the STATUS LED never turns on.
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Caution: Liquid nitrogen requires special handling. Read this section carefully before filling the dewar.
Caution: In confined spaces lacking adequate ventilation, nitrogen gas can displace air to the extent that it can cause asphyxiation. Always use and store liquid nitrogen in well-ventilated areas.
DSS-XXXL series liquid-nitrogen-cooled detectors
About liquid nitrogen
Caution: Never turn on the power to the DSS-15VP until the DSS-XXXL detector reaches operating temperature (77 K). Wait ten minutes. The pre-amplifier gain in the cryogenic detector heads is very high to take advantage of reduced thermal noise. If the detector is powered at higher temperatures, the pre-amplifier will saturate from high dark current from the detector. In this condition, the pre-amplifier can overheat. After a few minutes, damage can occur.
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About storage and transfer of liquid nitrogen
Instructions for filling a dewar with liquid nitrogen
1 Carefully fill the metal dewar with liquid nitrogen, using the funnel included with the equipment. Fill a little at a time to allow the boil-off vapor to escape. Filling too quickly at
first causes the liquid nitrogen to spurt out, forming a geyser. Fill the dewar
slowly over a five-minute period to reduce the geyser-effect.
Caution: Wait ten minutes after filling the dewar or adding liquid nitrogen before switching on electronics.
Caution: Always store liquid nitrogen in vacuum-insulated containers, loosely covered but not sealed. Covering prevents moisture from condensing out of the air to form ice which may cause blockage. Sealing results in
pressure build-up. NEVER ATTEMPT TO SEAL THE
MOUTH OF THE DEWAR!
The gas-to-liquid volume ratio is about 680:1. All containment vessels must therefore be fitted with exhaust vents to allow evaporating gas to escape safely. If these vents are sealed, pressure will build up rapidly and may result in the fracture of the containment vessel.
Caution: The boiling point of liquid nitrogen at atmospheric pressue is 77.3 K (about –196°C). This extreme cold can cause tissue damage similar to a severe burn. Therefore, avoid exposure of the skin and eyes to the liquid, cold gas, or liquid-cooled surfaces.
Handle the liquid so that it does not splash or spill. Wear goggles and gloves impervious to liquid nitrogen when handling the liquid. Protect feet by wearing rubber boots, with uncuffed trousers on the inside.
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2 Take care not to overfill.
3 To fill the detector head with liquid nitrogen, use the funnel provided with a transfer dewar. Ensure that the funnel fits loosely into the fill-hole to provide a gap to vent the
boiled-off vapor as the liquid nitrogen is added.
4 Set the funnel into the mouth of the dewar.
5 Pour the liquid nitrogen into the funnel slowly. When filling the dewar, an initial period of nitrogen-boiling occurs until the
internal components of the dewar have cooled to liquid-nitrogen temperature.
6 After the initial boil-off, refill the dewar as needed to extend the cold-temperature hold-time.
7 Replace the cap each time you fill the dewar. The cap is insulated to help extend the interval between fills. It also minimizes
moisture condensation into the dewar. The loose fit of the cap prevents pressure
build-up in the dewar by allowing evaporating nitrogen to escape.
If you draw power from your lock-in amplifier: The CCD-LKDSS is designed to draw the appropriate voltages to power the
preamplifier for an ambient or liquid-nitrogen-cooled DSS detector (i.e., not the
thermoelectrically cooled DSS detector) from a lock-in amplifier. It converts a 20 VDC
voltage from the lock-in amplifier to a 15 VDC voltage via a resistive circuit.
Required equipment
Ambient or liquid-nitrogen-cooled DSS detector
Stanford Research lock-in amplifier SR510, SR530, SR810, or SR830
Procedure
1 Connect male 15-pin end of cable J400402 to 15-pin female connector on converter box J400256.
Caution: If the liquid nitrogen is spilled on apparatus around or below the detector, the resulting thermal shock may have a detrimental effect.
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2 Connect 9-pin end of cable to 9-pin preamplifier port on back of lock-in amplifier.
3 Connect cable from DSS detector (9-pin female) to 9-pin end of converter box, to obtain ±15V and ground (earth) required for the DSS detector preamplifier. CCA-LKDSS connected
on left side to ambient
DSS detector, and on right
side to preamp port of
SR510 lock-in amplifier.
If you use controllers: Use the DSS-15VP low-noise
power supply. In this case, the
DSS-XXXL is supplied with a
short 18″ (46 cm) power cable
wired specifically for the DSS-
15VP power supply.
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High gain versus low gain Each DSS detector has an choice for setting the pre-
amplifier with high gain or low gain. Change the gain using
the toggle switch on the detector head. There is a factor of
approximately ten between high gain and low gain.
HORIBA Scientific generally recommends that you start
with the low-gain setting but your choice depends on actual
signal levels. The detector’s damage threshold is 10 mV, but
the pre-amplifier saturates at 10 V. Sample calculations are
shown in the Troubleshooting section.
Technical drawing of DSS case.
.12
.351.5 1.035 - 40 THD 2.2
HI
LO POWERCABLE
OUTPUTBNC
GAINSELECT
DB-9
1/4 - 20 MOUNTING HOLE/SCREW
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Focusing the detector See the next section for how to set up your data-acquisition. With data-acquisition
running, do this procedure.
1 Direct a bright white light-source into the spectrometer’s entrance.
2 Start the control software, and prepare to monitor increases and decreases in signal-level in real time. If you are using SynerJY
® software, go into RTC mode to monitor the signal in
real time.
3 Set the wavelength position on the spectrometer so that you can see visible light at the exit slit. Use 0 nm for the entrance slit and 0.5 nm for the exit slit.
For gratings blazed in the infrared, choose a higher order close to the blaze of
the grating.
For example, a Hg vapor lamp that emits a 546.1 nm line can be used in the
fourth order at 2.1844 μm. For a grating blazed at 2 μm, this will give a brighter
image than tuning to 546.1 nm.
4 Open the spectrometer’s slits carefully while observing the intensity of the signal.
Note: If the detector is not sensitive to visible light, replace the white-light source with one that emits in the usable wavelength range of the detector, and tune the spectrometer to a suitable wavelength.
Note: To avoid saturating the detector start with a narrow slit-width and gradually increase the slit widths as necessary. (For example, start with 0.05 mm and increase in increments of 0.5mm.)
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5 Move the detector head vertically while monitoring the strength of the signal.
6 When you are satisfied that the detector is positioned for highest signal-intensity, tighten the set screws to secure the detector.
7 You may make small adjustments to the x- and y-positions to further optimize optical coupling to the detector.
8 Recheck the focus.
9 Finish by tightening all mounting set screws.
10 Using a ⅛″ Allen key, tighten the no-mar detector screw in the adapter sleeve.
Note: As you move the detector, depending on whether you have too much or too little signal, you may have to reduce or increase the slit-widths. If you have too much signal and are saturating the detector, insert neutral-density filters to reduce the light intensity as it enters the spectrometer.
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Data-acquisition with a DSS detector Each DSS detector comes with its own datasheet, on which various detector
specifications are listed, including the bandwidth.
DC mode
Any detector which lists the bandwidth as “DC–xyz Hz” may be operated in DC mode.
this means that the signal cable may be connected directly to a Data Acquisition
Controller such as the SpectrAcq2, Synapse AuxIn channel, Symphony AuxIn channel,
Fluorolog® electronics, oscilloscope, or other electronic acquisition device that
measures a DC voltage between 0 and ±10 V. Usually photovoltaic detectors may be
operated in DC mode, but check the datasheet to confirm.
AC mode
Some DSS detectors list the bandwidth as “5–xyz Hz” (AC-coupled). In this case, the
detector must be used with a chopper and lock-in amplifier, sometimes called “AC
mode”, except for one type of experiment which will be discussed later.
All DSS detectors may be used using a chopper and lock-in amplifier. This AC-mode
type of measurement is recommended when performing measurements above 2000 nm
(2 µm), in order to distinguish the actual signal of interest from the ambient IR
background signal (e.g., heat in the environment).
How to set up an experiment in DC mode
1 Turn on the Data Acquisition Controller.
2 Connect the signal cable to the detector on one end (if it is not already hard-wired) and to the voltage input channel of the Data Acquisition Controller on the other end.
DSS detector
SpectrAcq2
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Photograph of data-acquisition with a DSS detector.
3 Start the software, and follow standard procedures.
DSS detector Synapse detector
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Use of a lock-in amplifier
General information
The ACH-C series Optical Chopper is most commonly used with a lock-in amplifier for
measurements using photoconductive detectors without DC compatible amplifiers, or
when a weak signal must be separated from a strong background. In such a
configuration, the light entering the spectrometer is modulated by the chopper. The
lock-in amplifier then selects the signal synchronous with the chopped light, producing
a DC voltage output. The output signal is digitized and sent to the computer via GPIB
or RS-232 communication. A sample configuration is shown below:
Triax 320
Lock-in AmplifierSignal In Reference In
Chopper Power
Supply
Sync Out
Photodetector
Light
Chopper
Sample
PC
USB
cable
RS232
cable
iHR 320
Experiment configuration showing photodetector measurement with a chopper and lock-in amplifier using the Sync Output signal from the chopper controller as a reference signal.
Considerations for a chopper system
Setup Place the ACH-C series Optical Chopper between the light source and the detector to
modulate the light to a specific frequency. When the circular blade rotates, the optical
signal is blocked by the spokes, letting light through the chopper at a specific rate. The
frequency of the blade rotation is determined by the chopper controller. The chopper
controller also sends a synchronizing signal to the lock-in amplifier.
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Place the chopper as close to the light source as possible. The closer to the light source
the chopper is placed, the less stray light will enter the system. When using a chopper
and a lock-in amplifier, only the light that is chopped is recovered.
In experiments that require the full intensity of the light to excite the sample, place the
chopper immediately after the sample.
Chopper frequency Set the frequency of the chopper within the acceptable time-response of the detector,
including any associated amplifiers. In addition, do not set the chopper frequency to any
frequency that is a harmonic of a power line (mains). For example, in the USA, AC
power is run at 60 Hz; thus do not set the chopper to 60 Hz, 120 Hz, 180 Hz, etc.
Lock-in time constant The time constant on the lock-in amplifier sets the amount of time it takes for the lock-
in amplifier to reach a stable measurement after a change in signal-level, such as
changing the spectrometer wavelength position. The time constant must be long enough
to allow for completion of several chopper periods. If the chopper frequency is 250 Hz
and thus the period is 4 ms, then the time constant would need to be 5 times as long,
approximately 20 ms.
For example, if the time constant is set to 1 ms, and the optical signal is suddenly
changed, the lock-in will not reach a stable value until 3 ms have passed. When setting
the parameters of a scan involving a lock-in, the dwell time for the monochromator
must be 3 to 5 times as long as the time constant.
This is summed up by the following relationship:
Dwell Time ≥ 3 × Time Constant ≥ 3 × 1/Chopper Frequency
Lock-in phase After setting the chopper time constant and dwell time for maximum reliability, the
next step is to correctly set the phase of the lock-in measurement. Some lock-in
amplifiers do this automatically, some have a button that auto-phases the measurement,
and some require a manual setting of the phase. Please refer to the lock-in amplifier’s
documents to see which option you have.
Caution: Never operate the chopper in High Frequency mode using the 3-slot blade. Damage to the optical sensor may result.
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Setting up a basic chopper system
1 Put a known light-source through the spectrometer system.
2 Turn on the ACH-C series Optical Chopper and set the frequency.
3 Using BNC cable, connect the reference signal from Sync Output (located on the chopper controller front panel) to the Reference In or Sync In receptacle of the lock-in amplifier.
4 After verifying that the detector is turned on, connect the signal BNC cable to the input channel of the lock-in amplifier.
5 Set the lock-in time constant.
6 Observe the lock-in front panel to see if it displays a signal. If the overload LED is lit, decrease the sensitivity (for example from microvolts
to millivolts). If a signal is not displayed, increase the sensitivity (typically
nanovolts is the highest unit of sensitivity).
7 If no signal is visible, check that the reference frequency sensed by the lock-in amplifier is the same as the frequency set on the chopper, and that it is stable.
8 When a signal is visible, gradually adjust the phase (either manually or by using the autophase button).
a For lock-in amplifiers having only manual phase capability, try the
“nulling technique” to find the best phase adjustment.
b To perform this technique, find a detectable signal, then add or subtract
90° to the phase (so that the signal is close to zero). Adjust the phase-
angle until the signal-level is as close to zero as possible. Change the
phase-angle back by 90° to obtain the optimal signal-level.
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c To check that you are seeing real optical signal, block the light.
d The signal on the lock-in should go to zero.
9 Set the software integration time to between 3 times and 5 times the value of the time constant, allowing the internal integration to stabilize.
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Transient-decay experiments (time-resolved) with digital storage oscilloscope (DSO)
Introduction
This type of experiment requires a pulsed light source, and measures luminescence
lifetimes. Select the light source and detector carefully so that the repetition rate of the
light source is compatible with the bandwidth of the detector. To estimate the fastest
lifetime that can be measure with a particular detector, the following equation may be
used:
Lifetime (mininum) = 0.2/(electronic bandwidth)
So in theory, a detector with 2 kHz bandwidth could measure a luminescence lifetime
of 100 µs or longer, depending on the repetition rate of the pulsed source. This type of
measurement may be performed with any appropriate DSS detector whether the
detector is AC coupled or not.
Method
1 Set spectrometer to emission wavelength of interest (based on spectrum measured previously)
2 Connect laser sync to DSO channel 1, trigger DSO on channel 1
3 Connect DSS detector signal cable to DSO channel 2
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Sample
MAX
L1
L1
Pulsed Laser
DS
S
Detector signal to Ch. 2
Laser sync to Ch. 1
Digital Storage
Oscilloscope
Diagram of a transient-decay set-up with digital storage oscilloscope.
Note: HORIBA Scientific does not offer software control of transient-decay experiments. The user must write software based on programming instructions from the Digital Storage Oscilloscope operation manual.
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3: Signal Optimization
Introduction The signal-to-noise ratio of the detected signal is dependent upon optical coupling,
temperature of the detector, the timing aspects of the technique to collect the signal, and
the electronic treatment of the signal after it leaves the detector.
Optical considerations The coupling of the optical signal from the exit slit of a monochromator to the active
area of the detector greatly affects the system’s performance. Detector areas that are
small are often desirable because they have better D* and NEP values. Detectors with
small active areas requre coupling optics to direct the diverging energy exiting the
spectrometer’s slit to be concentrated on the detector. The 1427C solid-state detector
interface uses a 6:1 elliptical mirror to collect achromatically the diverging beam and
focus the light onto the detector. A user-designed lens interface may also perform this
function, but the wavelength-range may be limited depending upon the lens material.
Chromatic aberration from the lens can shift the focus, causing uneven coupling as a
function of wavelength, also.
Thermal considerations The thermally-generated blackbody signal of the detector itself is a source of noise, but
this can be reduced by orders of magnitude by choosing a cooled detector. By reducing
the induced background noise contributions of the detector, the minimum detectable
signal-level can be lowered.
HORIBA Scientific offers two modes of cooling:
Thermoelectric (TE) cooling, operating at –30°C. The TE-cooled detectors are
mounted onto a two-stage Peltier cooling device with an integral heat sink. A
spearate power supply/temperature controller is provide to power and
thermostatically control the detector.
Liquid-nitrogen cooling, operating at –196°C (77 K). These devices are mounted in
a dewar able to hold liquid nitrogen over ten hours.
Uncooled detectors, operating nominally 20°C, are mounted in housings similar to the
TE units for ease of interchange.
Note: Cooling temperature affects the upper-wavelength response. For photodiode detectors, long-wavelength response is reduced. Photoconductors, however, exhibit enhanced response at longer wavelengths.
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Timing considerations The acquisition speed for the detector is based on the response time of the detector
along with the speed of the amplifier package. Photodiodes are generally very fast
detectors, able to respond to chopping speeds in the megahertz range. The amplifier
speed, however, at the set gain is slower, limiting the frequency response to just over
1000 Hz and a minimum datapoint time of 1 ms. Conversely, photoconductors tend to
be slower detectors. The lead sulfide detector is the slowest detector, with a
recommended operating frequency of 100 Hz, corresponding to a minimum datapoint
time of 10 ms. The lead selenide detector is faster, returning optimized performance at
1000 Hz. HgCdTe detectors can be run at chopper speeds in the range of 1000 Hz to
approximately 10 kHz to minimize their 1/f noise component.
Electronic considerations Photodiode-detector output can be collected in DC mode by connection to the voltage
input channel of a SpectrAcq2. On a Fluorolog®, contact HORBIBA, for other
electronics are required (such as a DM303). This minimal hardware configuration is
suitable when the signal is much larger than the noise, such as when measuring diode
responses, characterizing lamps, and running routine transmission/absorption spectra.
The total DC signal includes the signal of interest along with some background noise
caused by the environment, dark signal from the detector, and DC-amplifier offset. As
the signal levels increase or the accuracy needs to increase, additional signal-
conditioning is required. DC-signal collection is not suitable for photoconductors.
Background noise, detector noise, and offset of the DC signal can be suppressed by
operating in AC mode (also called synchronous or lock-in mode). AC operation is
mandatory for photoconductors, and recommended for photodiodes when the DC
signals are noisy. AC operation is commonly performed by using an optical chopper in
the experiment’s light path, and connecting the detector to a lock-in amplifier. The
chopper is a shutter which blocks and unblocks the optical path at a fixed frequency; it
is generally a series of equally-sized blades and holes on a motor-shaft, rotating at a
controlled rate. The chopper is placed closest to the light-source, modulating the signal
at the chopper frequency. The signal is then modulated while the noise and stray signals
that may be introduced layer in the optical system are not modulated. The lock-in
amplifier acts as a very narrow frequency bandpass filter to extract the modulated signal
from the total signal. By using a lock-in system, it is possible to acquire the
experimental signal at a desirable S/N from a much-larger background noise.
Photoconductors are susceptible to noise related to the inverse of the chopper frequency
(1/f noise), which climbs geometrically as the DC mode is approached. Therefore
photoconductors are always operated in the AC mode. Typcial chopping frequencies for
photoconductors range from 10 Hz to 2 kHz or faster, while photodiode detectors range
from DC to 500 Hz. Consult the datasheet for the specific response of your detector.
The maximum chopping frequency is dependent on the response time of the particular
detector type, and limits the fastest speed of data-acquisition.
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4: Troubleshooting
Introduction The DSS Series detectors are designed to peform for years with minimal maintenance.
The ambient and thermoelectrically-cooled heads typically require no further attention
once put in service.
Problems
Loss of vacuum in liquid-nitrogen-cooled detectors
The liquid-nitrogen-cooled detector heads are evacuated, and eventually will need re-
pumping. Because the level of vacuum required is beyond the capabilities of
mechanical vacuum pumps, Monthly checking of the dark-signal level indicates loss of
vacuum as the vacuum insulation performance degrades, and the dark current increases
from increased operating temperature. When the cooling can no longer maintain a
stable dark current, contact the factory for assistance. It may be possible to send the
detector back to the factory for repumping. Frost-formation on the outside of the dewar
and rapid consumption of liquid nitrogen indicate extreme vacuum loss.
Noisy signal
Try to increase signal strength at the detector.
Do what you can to eliminate or reduce the non-signal light that is allowed to enter
the spectrograph entrance slit, whether on the optical axis or not.
Check for light leaks as suggested under “Background signal too high” in this
section.
If noise is reduced by turning off or disconnecting the power to the spectrometer
motor, rearrange power connections to be sure the spectrometer, source, and
detector are tied to the same ground (earth) and, if possible, the same power circuit
(mains).
Adding redundant ground (earth) wires to various points in the total system often
helps to reduce the effect of electromagnetic noise sources. Ground loops and
electromagnetic interference can sometimes be challenging problems. Connecting
the detector head to a central ground may help. For DSS-XXXX heads, remove one
of the case screws near the cable end of the detector, scratch away the black
anodized coating in the countersink under the screw head, and tighten the screw
onto the wire. Connect the other end of the wire to the central ground (earth) point.
The central ground (earth) may be a rear-panel chassis ground on the controller or
lock-in amplifier. In extreme cases, some prefer to create a “star” ground (earth),
that is, a central point on a metal baseplate or optical table that has straps or wires
radiating to the various system components. In extreme cases, the best approach is
to patiently experiment by trying various combinations of grounding (earthing)
connections.
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As a general rule, try to keep ground (earth) wires short, make tight connections,
and avoid painted, coated, and anodized surfaces when possible. Leave no loose
ends.
In extreme cases, such as working with or around high-powered pulsed lasers or
other high-energy apparatus, it may be helpful to construct RFI/EMI shields or
cages to contain the noise at its source, or to isolate the detection system from the
noise. In these cases, colleagues who are working with similar apparatuses may be
your best resource for noise control suggestions.
Background is signal too high, background is reduced when room lights are turned off:
Be sure all covers are in place
Make sure that the area between the source or sample and the entrance slit is
enclosed, and light-tight. Block the entrance slit as a test.
Check detector mounting and housing for light-leaks.
Starting from the detector, close the exit and entrance slits and shutters in turn to
determine where stray light may be entering the system. To prevent damage to the
knife edges, the slits do not close completely, and will therefore not block all of the
light. However, with the signal blocked, reducing the slit width will reduce any
stray light that is passing through it.
Be sure all openings and screw holes are plugged.
Check that the cover, side, and baseplate fit tightly, and that foam or rubber light-
seals are partly compressed, not flattened.
If leaks persist, use a small flashlight in a dark room to isolate where the leaks are
by shining it at any suspicious part or joint in the system, and observing detected
signal levels.
Background signal is too high, background is not reduced when room lights are turned off:
For thermoelectrically-cooled heads, check for green STATUS light on DSS-15V-
TEP.
For liquid-nitrogen-cooled heads, check that the dewar is filled.
Acquire data with a background subtraction: Take a background scan under the
same conditions as the desired signal, but with the signal of interest blocked, and
then subtract the background from future scans of the signal of interest. Update the
background data periodically to compensate for long-term drift or other changes
that affect the system. If an automated shutter is available, use it to block the signal
and acquire background data at each point in the scan.
Use a chopper and lock-in amplifier to modulate and synchronously detect the
signal.
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Troubleshooting
45
Damage threshold and saturation level for detectors
Discussion
The maximum optical power or photon flux that should impinge on the detector
depends on two factors:
Damage threshold for the detector
Saturation level for the pre-amplifier
In most cases the detector’s pre-amplifier reaches saturation before the detector gets
damaged.
For all DSS-series detectors, the damage threshold is 10 mW (1 × 10–2
W), and the pre-
amplifier saturation is at 10 V. Therefore, under all measurement conditions, optical
power illuminationg the detector should be lower than these maxima.
In order to calculate the maximum optical power that may be used with a given
detector, use the detector responsivity (in units of V/W) provided on the datasheet.
Here is an example using the DSS-PS020T lead-sulfide detector:
Responsitivity (V/W)
Damage threshold (mW)
Maximum power (W)
Pre-amplifier saturation (V)
Maximum power, pre-amplifier (W)*
High
gain 2 × 10
7 1 × 10
–2 2 × 10
5 10 0.5 µW
Low
gain 2 × 10
6 1 × 10
–2 2 × 10
4 10 5 µW
*Maximum power is based upon preamplifier μW50V/W102
V107
Estimating the detection limit
There are several ways to estimate the detection limit. One way is to estimate the
minimum signal “typically” measured by a lock-in amplifier as 200 µV, and work
backwards. For the PbSe detector, assume that the saturation limit of 5 µW is
equivalent to 5 V (50% throughput caused by optical losses). Then 1 V on the lock-in
amplifier equals 1 µW; 1 mV on the lock-in amplifier equals 1 nW; likewise, 200 µV
on the lock-in amplifier equals 200 pW.
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Troubleshooting
46
For the MCT(14) detector, the responsivity is on the order of 2 × 105 V/W on high gain,
or a factor of 10× lower than PbSe. Using the same reasoning, the detection limit for
the MCT(14) detector is then 10 × 200 pW, or 2 nW.
Note: In actuality, there is a small amount of optical loss (20–30%) from chopping of the incoming light beam, but this is included in the 50% throughput estimate.
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Accessories
47
5 : Accessories Table III. Accessories available for DSS Detectors
Accessory Part Number Adapters or other parts required
One of these five is required for power: Regulated power supply for DSS ambient and liquid-nitrogen-cooled
systems. ±15V DSS-15VP
Two-channel regulated power supply for DSS ambient and liquid-
nitrogen-cooled systems. ±15V DSS-15VP-2C
Regulated power supply for DSS thermoelectrically cooled systems.
±15V DSS-15V-TEP
Cable, provides ±15V from SpectrAcq2 for DSS detectors. Requires
SpectrAcq2 CCA-SQ2DSS SPECTRACQ2
Cable to power ambient and liquid-nitrogen-cooled DSS detectors from
Stanford Research lock-in amplifiers CCA-LKDSS
(CLI-)SR810,
(CLI-)SR830,
(CLI-)SR510,
(CLI-)SR530
Other optional accessories: Male-to-male gender changer, 9-pin, that allows ambient or liquid-
nitrogen-cooled DSS detectors to obtain the necessary ±15V to power
the preamplifier from an existing DSS-15V-TEP
990078LF DSS-15V-TEP
Allows up to four DSS detectors to share one SpectrAcq2 data-
acquisition module J23078770 SPECTRACQ2
Enclosed compact chopper to mount onto entrance slit of
monochromator ACH-C J36540 or J35926
Open-head optical chopper ACH-C-OPEN
SpectrAcq2 data-acquisition system with one current-input channel and
one voltage-input channel SPECTRACQ2
Lock-in controller, single-phase, digital, SR810/830 CLI-SR810
CLI-SR830
ACH-C
or ACH-C-OPEN
Adapter to mount DSS silicon detector directly onto MicroHR slit DSS-1679A DSS-S025A or DSS-
S025T
SMA fiber-adapter to SM1-thread for thermoelectrically cooled DSS
detectors DSS-SMA
Housing for DSS detectors with elliptical mirror (6:1) 1427C
Housing for DSS detectors including gold-coated elliptical mirror (6:1) 1427C-AU
Recommended for
wavelengths above 550
nm
Dual 1427C T adapter with pivoting mirror to allow mounting of two
1427C adapters with two DSS detectors J23078370 1427C × 2
1427C housing for two detectors (two DSS or one DSS and one PMT) J23079050
1427C-AU with all cables and adapters for Fluorolog®-3
spectrofluorometer FL-1090
DSS detector and
Fluorolog®-3
2⅝″-bore collar for oversized detector housing J36788
Extension collar + three screws for liquid-nitrogen-cooled detector J352179
Additional sleeve for thermolectrically cooled or ambient detector J38268
Additional collar for liquid-nitrogen-cooled detector J36064
A-B switchbox to select between two input signals without
disconnecting cables. Useful for two-color detectors.
SWB-AB
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Accessories
48
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Glossary
49
6: Glossary ADC An Analog to Digital Converter (ADC) converts a sample of an
analog voltage or current signal to a digital value. The value may
then be communicated, stored, and manipulated mathematically.
The value of each conversion is generally referred to as a datapoint.
Blackbody
radiation
An ideal blackbody completely absorbs all radiation that strikes it.
Blackbody radiation is the emission from a blackbody when
heated. All objects at temperatures above absolute zero emit some
radiation. For convenience, this emission is often referred to as
blackbody radiation.
Chromatic
aberration
Lenses do not form perfect images at a single point or plane when a
polychromatic source is used. This is caused by the refraction of
different wavelengths at slightly different angles. This same
phenomenon is what makes a prism split a collimated beam of
white light into diverging colors. Sometimes the displacement is
significant, such as when imaging into a narrow spectrometer slit
and working over a broad range of wavelengths. In such cases,
throughput may vary considerably as a function of wavelength. The
effect can be visualized as multiple images formed at slightly
displaced positions along the optical axis. The distance from the
lens to each image is a function of the wavelength of that image
and the index of refraction of the lens at that wavelength. Images
that are formed in front or behind the slit will not couple to other
optical components as well as the image that is formed at the slit
plane.
D* (pronounced dee-star; units are cm·Hz½/W) This is an area-
weighted figure of merit for detectors. The higher the D* value, the
more sensitive the detector. To realize the best performance in a
spectroscopic system, coupling optics are often required to collect
the divergent beam from the exit slit and concentrate it on the small
(therefore high D*) detector. D* is dependent on detector area and
NEP.
Dark signal Dark signal is generated by thermal agitation. This signal is directly
related to exposure time, and increases with temperature. The more
dark signal, the less dynamic range is available for experimental
signal.
Dynamic range The dynamic range is the ratio of the maximum signal to the
minimum signal measurable. The weakest detectable signal is
limited by the dark level plus the sampling noise. For single-
channel detectors, the most intense detectable signal is the lesser of
the saturation level or the ADC maximum limit. The dynamic
range of the detector can be greater than that of the system as a
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Glossary
50
whole (which is limited by the ADC). A 16-bit ADC limit is 65
535 (216
–1) counts. A 14-bit ADC is limited to 16 383 counts. Gain
ranges can be used to shift the ADC range to match the signal-
levels of a given spectral measurement. In this way, stronger or
weaker signals can be accommodated with optimal dynamic range.
Linearity When photo response is linear, if the light intensity doubles, the
detected signal will double in magnitude as well. Although not a
detector-specific term, another related type of linearity is the
spectral positioning accuracy, or tracking error, of a spectrometer’s
drive mechanism.
NEP NEP stands for Noise Equivalent Power. This is the radiant power-
level impingíng on a detector that results in a signal-to-noise ratio
of 1:1. NEP is specified at a particular modulation frequency,
wavelength, and effective noise bandwidth. A lower NEP value
means more detector sensitivity. The NEP is also improved by
detector cooling.
Noise Noise is common to all detectors. The total amount of signal that
exists is less important than the ratio of signal magnitude to noise
magnitude (S/N). With a high signal-to-noise ratio, a signal peak
can be discerned even though actual counts per second may be low.
Types of noise:
Amplifier noise: Some noise is introduced in the process of
electronically amplifying and conditioning the signal read from the
detector before conversion to a digital value. Part of sampling
noise.
Conversion noise: During the conversion of an analog signal to a
digital datapoint, some electroníc noise is introduced, and
statistical variations occur in the least-significant bit of the
converted data. Part of sampling noise.
Dark noise: The detector integrates a thermally-generated dark
current at all times, whether light is reaching the detector or not.
Most of the dark current is a steady-state level that can be
subtracted, and so does not ultimately contribute to the noise.
However, a component of dark current is dark noise caused by
statistical variations in the dark current. The dark noise component
increases as the square root of the dark current. Dark current, and
therefore dark noise, can be reduced by cooling.
Sampling noise: Electronic noise impressed on the signal during
the amplification and digitization of the signal. For convenience,
usually all of the noise associated with biasing, amplifying, and
converting the signal are considered as sampling noise.
Shot noise: This is due to the random statistical variations of light.
It includes both experimental and dark-signal components. Shot
noise is equal to the square root of the number of electrons
generated. lts effect can be minimized by increasing signal
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Glossary
51
intensity, signal integration time, or summing a number of samples.
Photodiode
detector
Photodiode devices generate a voltage or current as a result of
photons impinging on the junction. Connection to support
electronics is straightforward, because photodiodes often require
only amplification to boost the current or voltage to a level
sufficient for accurate digitization.
Photoconductive
detector
This type of detector decreases resistance in response to increases
in photon flux. Photoconductive detectors require a biasing voltage
and usually lock-in (synchronous) signal-processing, to extract the
signal from the inherent noise that is characteristic of this class of
detectors.
Photoelectric
effect
Some materials respond to illumination from photons by releasing
electrons. When light of sufficient energy hits a photosensitive
material, an electron is freed from being bound to a specific atom.
Such materials include the P-N junctions of photodiodes. The
energy of the incident light must be greater than or equal to the
binding energy of the electron to free an electron. The shorter the
wavelength, the higher the energy the light has.
Photoelectron A photoelectron is an electron that is released through the
interaction of a photon with the active element of a detector. The
photoelectron may be released either from a junction to
theconduction band of a solid-state detector, or from the
photocathode to the vacuum in a PMT. A photoelectron is
indistinguishable from other electrons in any electrical circuit.
Quantum detector Quantum detectors interact with the photons directly in their
electronic structure. These are the most sensitive solid-state
detectors for general spectroscopic use. The two types of quantum
detectors are photodiodes and photoconductors.
Quantum
efficiency
(QE) The quantum effìciency is the quantity of photoelectrons
produced by a detector expressed as a percentage of the quantity of
photons incident on that detector. A QE of 20% means that five
photons produce a single photoelectron. Detectors made of silicon
yield about 45–50% peak QE at 750 nm. The QE of a detector is
determined by several factors. These include the material’s
intrinsic electron binding-energy (or band gap), the reflectivity of
the surface, the thickness of the surface, and energy of the
impinging photon (hν). QE varies with the wavelength of incident
light.
Responsivity Responsivity is the ratio of output voltage to corresponding
exposure (µJ/cm2). Usually the responsivity is reported in units of
V/W. Technically it is measured at VSat min/2 under specified
conditions of illumination, sample rate, and temperature.
S/N (Signal-to-noise ratio) For any given signal, there is some noise
present. S/N is the ratio of the desired signal-level over the
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Glossary
52
associated noise-level. The higher the S/N, the cleaner the signal.
Saturation level The maximum signal-level that can be accommodated by a device
is its saturation level. Beyond this level, further increase in input
signal does not result in a corresponding increase in output. This
term is often used to describe the upper limit of a detector element,
an amplifier, or an ADC.
Spectral response Most detectors will respond with higher sensitivty to some
wavelengths than to others. The spectral response of a detector is
often expressed graphícally in a plot of responsivity versus
wavelength. The graphs on page 12 show the spectral response of
several detectors.
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) AC (Mains) Power Selection and Fuses
53
7: AC (Mains) Power Selection and Fuses
Introduction The DSS-15V-TEP power supply and thermoelectric cooler controller has a power-
input module on the back panel. This module combines the line-voltage selection, fuse-
holder and power line-cord entry into one compact unit.
To change the fuse
1 Disconnect the line cord.
2 Slide the cover open.
3 Pull the lever to remove the fuse. Inside the fuse cavity, there is a small circuit board inserted to select the line
voltage. There is a voltage selection board which has four possible positions,
and is labeled so that the present line-voltage setting shows below the fuse.
Table IV. Fuses
Line (mains) voltage Fuse rating (3AG type)
120 VAC 0.5 A fast blow
240 VAC 0.5 A fast blow
Note: Note that only the 120 and 240 settings are valid, and will work for 100 V and 220 V line voltages (mains) respectively.
ACH-C and ACH-C-OPEN Phase-Locked-Loop Optical Choppers Operation Manual rev. D (14 June 2013) Specifications
54
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) How to Choose a Detector
55
8: How to Choose a Detector
Introduction lf the need arises for higher sensitivity, or to cover wavelengths beyond the capabilities
of the detector(s) originalty ordered, HORIBA Scientific offers this section to assist in
selecting additional detectors as needed.
Wavelength
The first parameter for selection of a solid-state detector is the wavelength range. This
typically narrowws the choice down to a few types of detector. To choose between a
photoconductor and a photodiode, for high signal-level one may simplify the electronics
by operating in DC mode with a photodiode. AC mode is preferred when the optical
S/N is not as good. AC mode is the only choice for photoconductors.
Highest D*
Next, choose the detector with the highest D. Signal-to-noise ratio (and therefore D*) is
also improved by detector cooling. While thermoelectric cooling is usually the most
convenient, liquid-nitrogen cooling yields the highest sensitivity. Highest D* is related
to lowest NEP.
Some choices
Silicon detectors
Silicon detectors are recommended for studies to 1.1 µm; remember that a PMT has
higher gain and will outperform a silicon detector through most of its photocathode
response range. The DSS-S025A and DSS-S025T silicon detectors may be directly
coupled to the MicroHR spectrometer using the 1679A. The mirror-based 1427C
detector interface allows for coupling to all other HORIBA spectrometers and also
provides interchangeability between silicon and other DSS detectors.
Other materials
Near-IR For the wavelength range of 1.1–1.7 µm, the DSS-IGAXX InGaAs detectors offer the
highest sensitivity. We recommend them over the DSS-GXX germanium detectors
when the maximum wavelength is still within range. The DSS-GXX germanium
detectors give an additional 100 nm of spectral range to 1.8 µm.
Longer wavelengths For longer wavelengths, select the DSS-ISXX indium antimonide, if cryogenic cooling
is suitable. Otherwise, the DSS-PSXX lead sulfìde and then the DSS-PSEXX lead
selenide detectors are next best-suited.
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) How to Choose a Detector
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The DSS-IAXX indium arsenide offers DC operation at a lower performance-level for
much of the same range.
Mercury-cadmium-telluride The DSS-MCT offers the longest detection range. The detector is optimized for peak
response through the alloy-mixture ratios; performance is traded for range. Specify
desired peak and maximum wavelength when ordering.
Visible + one other wavelength Two-color detectors extend the range of the IR detectors to the visible range at some
efficiency penalty. A wide variety of detectors are available for spectroscopic
applications. Selection is based on maximizing signal and reducing noise. The four
major issues to consider in the selection are:
Wavelength range
Acquisition electronics
Temperature control
Detector performance ratings
Wavelength range The first criterion used in selecting a detector is wavelength-coverage. The detector
must be operable over the wavelength-range required. The chart below illustrates
various detectors’ nominal wavelength-coverage, without respect to detector efficiency.
Detector wavelength coverage.
Silicon detectors generally are less sensitive than photomultiplier-tube (PMT) detectors
when operating in the UV-visible range of approximately 200–700 nm. Factors such as
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) How to Choose a Detector
57
durability, no requirement for high-voltage power supplies, cost, and size often favor
solid-state detectors even when operating in the UV-VIS range. As the wavelengths
approach 1 µm, most PMTs become insensitive, and silicon and other solid-state
detectors are favored.
To some extent the operating temperature of the detector affects the upper limit of its
wavelength-range. A photodiode loses range, but a photoconductor gains range as the
detector’s operating temperature is lowered.
When it is necessary to cover a wider wavelength-range than a single delector can
handle, for best sensitivity, use two detectors. An automated exit-port selection mirror
installed in the spectrometer can be used to switch between detectors during an
acquisition scan. Otherwise the detectors can be interchanged manually as part of a
change in system configuration between measurement sessions. This latter method may
require some alignment of the detector position, depending on the detector interface
used.
Without mechanically switching detectors, a “two-color” detector may be employed.
These devices take advantage of silicon’s transparency beyond 1.1 µm by mounting a
second detector behind the silicon chip. The silicon detects wavelengths shorter than
1.1 µm while passing longer wavelengths to the back detector. The silicon device
attenuates approximately 40% of the signal passing to the back detector, but greatly
simplifies the optical system. The two signals are available at separate BNC connectors
for noise-isolation and ease of connection.
The specifications chart in the next section summarizes characteristics for the most
popular DSS detectors.
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DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Technical Specifications
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9: Technical Specifications
Specification chart Table V: Table of Specifications
Material Spectral range,
µm Part number NEP
Active size, mm
D* (higher = better)
Cooling Bandwidth
HG/LG
Si 0.2–1.1 DSS-S025A 1.50 ×
10–14
2.5 mm Ø 1.48 × 10
14 RT
DC–
500H/2000L
Si 0.2–1.0 DSS-S025T 1.00 ×
10–14
2.5 mm Ø 2.22 × 10
14 TE
DC–
500H/2000L
InGaAs 0.8–1.7 DSS-IGA020A 5.00 ×
10–14
2 mm Ø 3.54 × 10
13 RT DC–2 kHz
InGaAs 0.8–1.65 DSS-IGA020T 1.50 ×
10–14
2 mm Ø 1.18 × 10
14 TE DC–2 kHz
InGaAs 0.8–1.55 DSS-IGA020L 1.00 ×
10–15
2 mm Ø 1.77 × 10
15 LN2
DC–
150H/500L
InGaAs-ext 1.0–2.05 DSS-IGA(1-9)010T 1.00 ×
10–13
1 mm Ø 8.86 × 10
12 TE DC–2 kHz
InGaAs-ext 1.0–1.9 DSS-IGA(1-9)010L 2.00 ×
10–14
1 mm Ø 4.43 × 10
13 LN2
DC–
500H/2500L
InGaAs-ext 1.2–2.4 DSS-IGA(2-2)010T 5.00 ×
10–13
1 mm Ø 1.77 × 10
12 TE DC–2 kHz
InGaAs-ext 1.3–2.2 DSS-IGA(2-2)010L 1.00 ×
10–13
1 mm Ø 8.86 × 10
12 LN2
DC–
500H/2500L
Ge 0.8–1.6 DSS-G020T 5.00 ×
10–14
2 mm Ø 3.54 × 10
13 TE DC–2 kHz
Ge 0.8–1.5 DSS-G020L 2.50 ×
10–15
2 mm Ø 7.09 × 10
14 LN2
DC–
500H/2000L
PbS 1.0–2.8 DSS-PS020T 3.00 ×
10–13
2 × 2 6.67 × 10
12 TE 5–400 Hz std.
PbSe 1.0–4.5 DSS-PSE020T 2.00 ×
10–11
2 × 2 1 × 10
11 TE 5–10 kHz
HgCdTe 1.0–5.0 MCT(5)020T 2.00 ×
10–11
2 × 2 1 × 10
11 TE 5–10 kHZ
InSb 1–5.4 DSS-IS020L 1.48 ×
10–11
2 mm Ø 1.2 × 10
11 LN2 DC–2500
HgCdTe 2.0–14.0 DSS-MCT(14)020L 5.00 ×
10–12
2 × 2 4 × 10
11 LN2 5–10 kHz
InAs 1.0–3.4 DSS-IA020T 1.00 ×
10–11
2 mm Ø 1.77 × 10
11 TE DC–10 kHz
All specifications are subject to change without notice.
Two-color or fast-bandwidth detectors, or other options: Contact HORIBA.
The pre-amplifer maximum signal has an output voltage swing of ±10 V into a 5 kΩ
or greater load.
Liquid-nitrogen-cooled heads have a temperature hold-time of > 10 h.
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Technical Specifications
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Detector sensitivity curves All specifications are subject to change without notice.
InGaAs, DSS-IGA020 series
Thermoelectrically cooled
Liquid-nitrogen cooled
Ambient temperature
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InSb, DSS-IS020L, liquid-nitrogen-cooled
Ge, DSS-G020 series
Liquid-nitrogen-cooled
Thermoelectrically cooled
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PbSe, DSS-PSE020 series
DSS-PSE020T,
thermoelectrically-cooled
DSS-PSE020A, ambient-
temperature
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Si photodiode, DSS-S025X series
DSS-S025T, thermoelectrically-cooled
DSS-S025A, ambient temperature
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HgCdTe, DSS-MCT-series, liquid-nitrogen-cooled
DSS-MCT(20)020L
DSS-MCT(20)020L
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Technical Specifications
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PbS, DSS-PS020 Series
Thermoelectrically-cooled, DSS-
PS020T
Ambient temperature, DSS-
PS020T
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Liquid-nitrogen-cooled dewar All specifications are subject to change without notice.
Specifications Amplifier Dual-gain transimpedance amplifier
Field of view 60° nominal
Package LN7 downview dewar
Hold time 10 hours nominal
Spectrometer adapter
1427C or 1427C-AU
Power requirements
±9 VDC to ±15 VDC
Connections BNC signal output. Shielded power cable terminated with DB-9
connector directly couples to DSS-15VP Low-Noise Power Supply.
Also compatible with CCA-SQ2DSS and CCA-LKDSS
Technical drawing
(all measurements are in inches)
Technical drawing of the DSS liquid-nitrogen-cooled dewar.
FILL PORT CAP0.5" DIA PORT
.300 NOMOUTER WINDOW
SURFACE TO DETECTOR
EVACUATION
PORT/PLUG
2.50 DIA
6.75
EVACUATION
PORT/PLUG
1.0
2.125
4.0
OUTPUT CABLE
GAINSELECT
POWER CABLE
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67
Electrical connections
DB-9 PIN OUT
1 NO CONNECT
2 NO CONNECT
3 NO CONNECT
4 NO CONNECT
5 NO CONNECT
6 +V
7 –V
8 GND
9 CASE GND
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Ambient-temperature detector All specifications are subject to change without notice.
Specifications Power requirements
±9 VDC to ±15 VDC
Connections BNC signal output. Shielded power cable terminated with DB-9
connector directly couples to DSS-15VP Low-Noise Power Supply.
Also compatible with CCA-SQ2DSS and CCA-LKDSS
Spectrometer adapter
1427C or other
Technical drawing
(All measurements are in inches)
Technical drawing of the ambient-temperature DSS detector.
Electrical connections
DB-9 PIN OUT
1 NO CONNECT
2 NO CONNECT
3 NO CONNECT
4 NO CONNECT
5 NO CONNECT
6 +V
7 –V
8 GND
9 CASE GND
.12
.351.5 1.035 - 40 THD 2.2
HI
LO POWERCABLE
OUTPUTBNC
GAINSELECT
DB-9
1/4 - 20 MOUNTING HOLE/SCREW
+
_
AOUTPUT
HI / LO SWITCH
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69
Thermoelectrically cooled and two-color head
All specifications are subject to change without notice.
Specifications Power requirements
±9 VDC to ±15 VDC
Connections Two shielded signal cables terminated with a BNC. Shielded power
cable terminated with a DB-9 connector directly couples the unit
with the DSS-15V-TEP power supply.
Spectrometer adapter
1427C
Technical drawing
(All measurements are in inches)
Technical drawing of the two-color DSS detector.
Electrical connections
DB-9 PIN OUT
1 COOLER +
2 COOLER –
3 THERMISTOR
4 THERMISTOR
5 NO CONNECT
6 +V
7 –V
8 GND
9 CASE GND
.12
.351.51.035 - 40 THD 2.2
HI
LO
1/4 20 MOUNTING SCREW/HOLE
DB-9
HI
LO
DET 1 OUTPUTTO BNC
DET 2 OUTPUTTO BNC
+
_
A
THERMISTOR
TEC
+_
OUTPUT
HI / LO SWITCH
+
_
A
HI / LO SWITCH
OUTPUT
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Technical Specifications
70
DSS-15V-TEP Power Supply Applications DSS-XXXT
Output voltage ±15V
Current ±100 mA
Regulation 0.02% line and load
Ripple 0.5 mV RMS max
output
Connector 9- pin D male connector
Input power 120 VAC, 0.5 A or
240 VAC, 0.5 A
Technical drawing of the DSS-15V-TEP Power Supply.
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71
DSS-15VP Power Supply
Applications DSS-XXXL, DSS-XXXA
Ouptut voltage ±15V
Current ±100 mA
Regulation 0.02% line & load
Ripple 0.5 mV RMS max. output
Connector 9- pin D male connector
Input Power 120 VAC, 0.5 A and 240 VAC, 0.5 A
Technical drawing of the DSS-15VP Power Supply.
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DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Service Information
73
10 : Service Information
Service policy If you need assistance in resolving a problem with your instrument, contact our
Customer Service Department directly, or if outside the United States, through our
representative or affiliate covering your location.
Often it is possible to correct, reduce, or localize the problem through discussion with
our Customer Service Engineers.
All instruments are covered by warranty. The warranty statement is printed inside of
this manual. Service for out-of-warranty instruments is also available, for a fee. Contact
HORIBA Instruments Incorporated or your local representative for details and cost
estimates.
If your problem relates to software, please verify your computer's operation by running
any diagnostic routines that were provided with it. Please refer to the software
documentation for troubleshooting procedures. If you must call for Technical Support,
please be ready to provide the software serial number, as well as the software version
and firmware version of any controller or interface options in your system. The software
version can be determined by selecting the software name at the right end of the menu
bar and clicking on “About.” Also knowing the memory type and allocation, and other
computer hardware configuration data from the PC’s CMOS Setup utility may be
useful.
In the United States, customers may contact the Customer Service department directly.
From other locations worldwide, contact the representative or affiliate for your location.
In the USA: HORIBA Instruments
Incorporated
3880 Park Avenue
Edison, New Jersey 08820
USA
Tel: +1-732-494-8660 Ext. 160
Fax: +1-732-494-9796
Email:
In France: Jobin Yvon SAS
16-18 rue du Canal
91165 Longjumeau Cedex
France
Tel: +33 (0) 1 64 54 13 00
Fax: +33 (0) 1 69 09 93
19
Worldwide:
+1-877-546-7422 China: +86 (0) 10 6849
2216
Germany: +49 (0) 89
462317-15
Italy: +39 (0) 2 57603050
Japan: +81 (0) 3 58230141
UK: +44 (0) 20 8204 8142
If an instrument or component must be returned, the method described on the following
page should be followed to expedite servicing and reduce your downtime.
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) Service Information
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Return authorization All instruments and components returned to the factory must be accompanied by a
Return Authorization Number issued by our Customer Service Department.
To issue a Return Authorization number, we require:
The model and serial number of the instrument
A list of items and/or components to be returned
A description of the problem, including operating settings
The instrument user’s name, mailing address, telephone, and fax numbers
The shipping address for shipment of the instrument to you after service
Your Purchase Order number and billing information for non-warranty services
Our original Sales Order number, if known
Your Customer Account number, if known
Any special instructions
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Warranty For any item sold by Seller to Buyer or any repair or service, Seller agrees to repair or
replace, without charge to Buyer for labor or materials or workmanship of which Seller
is notified in writing before the end of the applicable period set forth below, beginning
from the date of shipment or completion of service or repair, whichever is applicable:
a. New equipment, product and laboratory apparatus: 1 year with the following
exceptions:
i. Computers and their peripherals
ii. Glassware and glass products.
b. Repairs, replacements, or parts – the greater of 30 days and the remaining
original warranty period for the item that was repaired or replaced.
c. Installation services – 90 days.
The above warranties do not cover components manufactured by others and which are
separately warranted by the manufacturer. Seller shall cooperate with Buyer in
obtaining the benefits of warranties by manufacturers of such items but assumes no
obligations with respect thereto.
All defective items replaced pursuant to the above warranty become the property of
Seller.
This warranty shall not apply to any components subjected to misuse due to common
negligence, adverse environmental conditions, or accident, nor to any components
which are not operated in accordance with the printed instructions in the operations
manual. Labor, materials and expenses shall be billed to the Buyer at the rates then in
effect for any repairs or replacements not covered by this warranty.
This warranty shall not apply to any HORIBA Instruments Incorporated manufactured
components that have been repaired, altered or installed by anyone not authorized by
HORIBA Instruments Incorporated in writing.
THE ABOVE WARRANTIES AND ANY OTHER WARRANTIES SET FORTH IN
WRITING HERIN ARE IN LIEU OF ALL OTHER WARRANTIES OR
GUARANTEES EXPRESSED OR IMPLIED, INCLUDING WARRANTIES OF
MERCHANTABILITY, FITNESS FOR PURPOSE OR OTHER WARRANTIES.
The above shall constitute complete fulfillment of all liabilities of Seller, and Seller
shall not be liable under any circumstances for special or consequential damages,
including without limitation loss of profits or time or personal injury caused.
The limitation on consequential damages set forth above is intended to apply to all
aspects of this contract including without limitation Seller’s obligations under these
standard terms.
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DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) CE Compliance Information
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11: Compliance Information
Declaration of Conformity Manufacturer: HORIBA Instruments Incorporated
Address: 3880 Park Avenue
Edison, NJ 08820
USA
Product Name:
Product Model Numbers:
DSS Detectors with Controller
DSS-IGAXXXX DSS Detectors
DSS-15V-TEP DSS Controller
Conforms to the following Standards:
Safety: EN 61010-1: 2001
EN 61010-1: 2001/AC: 2002
EMC: EN 61326-1: 2006 (Emissions & Immunity)
Supplementary Information The product herewith complies with the requirements of the Low Voltage Directive
2006/95/EC and the EMC Directive 2004/108/EC.
The CE marking has been affixed on the device according to Article 8 of the EMC
Directive 2004/108/EC.
The technical file and documentation are on file with HORIBA Instruments
Incorporated.
______________________________
Salvatore Atzeni
Vice-President, Retail Engineering
HORIBA Instruments Incorporated
Edison, NJ 08820
USA
Nov 14, 2011
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) CE Compliance Information
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Applicable CE Compliance Tests and Standards
Test Standards
Emissions, Radiated/Conducted EN 55011: 2006
Radiated Immunity IEC 61000-4-3: 2006
Conducted Immunity IEC 61000-4-6: 2008
Electrical Fast Transients IEC 61000-4-4: 2004
Electrostatic Discharge IEC 61000-4-2: 2008
Voltage Interruptions IEC 61000-4-11: 2004
Surge Immunity IEC 61000-4-5: 2005
Magnetic Field Immunity IEC 61000-4-8: 2009
Harmonics IEC 61000-3-2: 2006
Flicker IEC 61000-3-3: 2008
Safety EN 61010-1: 2001
EN 61010-1: 2001/AC: 2002
DSS Series Solid-State Detectors Operation Manual rev. C (18 June 2013) CE Compliance Information
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12: Index
1
1/f noise .............................................. 42
1427C .. 9–11, 14–16, 20, 25, 41, 47, 55,
66, 68–69
1427C-AU .......................... 9–10, 47, 66
1428-series ......................................... 20
9
990078LF ..................................... 10, 47
A
AC mode ................................ 33, 42, 55
ACH-C ............................. 10, 35, 37, 47
ACH-C-OPEN ............................. 10, 47
alignment target.................................. 18
Allen key .................... 15–16, 19, 20, 32
ambient temperature detector 12, 14, 21,
60, 63, 65
ambient-temperature detector ...... 62, 68
AuxIn channel .................................... 33
B
background noise ......................... 41–42
bandwidth ........................................... 59
C
cable9–10, 12, 21–24, 28–29, 33, 37, 39,
43, 47, 66, 68–69
catalog numbers ................................. 11
caution notice ....................................... 4
CCA-LKDSS ... 9–10, 22, 29, 47, 66, 68
CCA-LKOSS ..................................... 12
CCA-SQ2DSS ....... 9–10, 12, 47, 66, 68
CCD-LKDSS ............................... 22, 28
CE Compliance Tests and Standards . 78
centering target ................................... 15
chopper ........... 10, 33, 35–37, 42, 44, 47
frequency considerations ................ 36
chromatic aberration .................... 41, 49
collar ................................ 10, 16, 20, 47
contact information ............................ 73
controller ................................ 35, 37, 73
converter box ......................... 22, 28–29
COOLER CURRENT meter ............ 25
D
D* ..................................... 41, 49, 55, 59
damage threshold ......................... 30, 45
danger to fingers notice ........................ 5
DC mode ................................ 33, 42, 55
Declaration of Conformity ................. 77
detection limit .............................. 45, 46
detector adapter ............................ 11, 17
detector head . 11, 13–14, 17, 20, 25, 28,
32, 43
detector saturation .............................. 45
digital storage oscilloscope .......... 39–40
disclaimer ............................................. 2
disconnect instrument .......................... 6
DM303 ............................................... 42
D-shell connector ......................... 22, 24
DSO.................................................... 39
DSS-15V/TEP .......................... 9, 12–13
DSS-15VP . 9–10, 12–13, 21–22, 29, 47,
66, 68, 71
DSS-15VP-2C .............................. 10, 12
DSS-15V-TEP 10, 24, 44, 47, 53, 69, 70
DSS-1679A ........................ 9–11, 17, 47
DSS-G020 series ................................ 61
DSS-G020L ........................................ 59
DSS-G020T........................................ 59
DSS-IA020T ...................................... 59
DSS-IGA(1-9)010L............................ 59
DSS-IGA(1-9)010T ........................... 59
DSS-IGA(2-2)010L............................ 59
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DSS-IGA(2-2)010T ........................... 59
DSS-IGA020 series ............................ 60
DSS-IGA020A ................................... 59
DSS-IGA020L ................................... 59
DSS-IGA020T ................................... 59
DSS-IS020L ................................. 59, 61
DSS-MCT(14)020L ........................... 59
DSS-MCT(20)020L ........................... 64
DSS-MCT-series ................................ 64
DSS-PS020 Series .............................. 65
DSS-PS020T ................................ 59, 65
DSS-PSE020 series ............................ 62
DSS-PSE020A ................................... 62
DSS-PSE020T ............................. 59, 62
DSS-S025A .......... 10–11, 47, 55, 59, 63
DSS-S025T .......... 10–11, 47, 55, 59, 63
DSS-S025X series .............................. 63
DSS-SMA .................................... 10, 47
E
electric shock notice ............................. 5
elliptical mirror .......... 10–11, 14, 41, 47
entrance slit ...................... 10, 43, 44, 47
excessive humidity notice .................... 5
exit slit .............................. 11, 14, 18, 41
extreme cold notice .............................. 4
F
face-shield ............................................ 5
FHR .................................................... 15
firmware ............................................. 73
FL-1090 .................................... 9–10, 47
Fluorolog®-3 .................... 10, 33, 42, 47
funnel ........................................... 27–28
fuse ..................................................... 53
G
gender changer ............................. 10, 47
germanium detectors .......................... 55
GPIB................................................... 35
gratings ......................................... 18, 31
H
Hg vapor lamp .............................. 18, 31
HgCdTe detectors .............................. 42
high gain ....................................... 30, 46
holder sleeve ...................................... 20
HORIBA Scientific
contact information 73
return authorization 74
hot equipment notice ............................ 5
I
iHR ............................................... 15–16
indium antimonide detector ............... 55
indium arsenide detector .................... 56
InGaAs detectors ................................ 55
intense light notice ............................... 4
J
J22644 ................................................ 15
J22645 ................................................ 15
J23078370 .................................... 10, 47
J23078770 .................................... 10, 47
J23079050 .................................... 10, 47
J352179 .................................. 10, 20, 47
J35926 .......................................... 10, 47
J36064 .................................... 10, 20, 47
J36540 .......................................... 10, 47
J36788 .................................... 10, 20, 47
J38268 .............................. 10, 18, 20, 47
J400256 ........................................ 22, 28
J400402 ........................................ 22, 28
J80135 .................................................. 9
L
lead selenide detector ................... 42, 55
lead sulfide detector ............... 42, 45, 55
light leaks ........................................... 43
liquid nitrogen10, 12–14, 20–22, 26–28,
41, 43–44, 47, 55, 59–61, 64, 66
lock-in amplifier .. 10–12, 22–23, 28–29,
33, 36–37, 42–45, 47
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loss of vacuum ................................... 43
low gain .............................................. 30
M
Material Safety Data Sheets ................. 2
MCT(5)020T ...................................... 59
MicroHR .............. 10–11, 15–17, 47, 55
monochromator .......... 10, 17, 36, 41, 47
MSDS ................................................... 2
N
NEP ............................ 41, 49–50, 55, 59
noisy signal ........................................ 43
nulling technique ................................ 37
O
optical chopper ........... 10, 42, 35, 37, 47
optical interface .................................. 11
P
photoconductor ................ 11, 42, 55, 57
photodiode........................ 11, 42, 55, 57
photomultiplier-tube .......................... 56
photovoltaic detectors .................. 11, 33
PMT ................................. 10, 47, 55, 56
POWER indicator LED .................... 24
power supply ... 9–13, 21–22, 29, 41, 47,
53, 66, 68–71
POWER switch ................................. 25
protective gloves .................................. 5
R
read this manual notice ........................ 5
return authorization ............................ 74
RS-232 ............................................... 35
RTC mode ......................................... 31
S
safety goggles ....................................... 5
safety summary .................................... 4
serial number ................................ 73–74
Service Department ...................... 73–74
service policy ..................................... 73
setup
chopper system 37
signal-to-noise ratio ........................... 41
silicon detector ..... 10–11, 17, 47, 55–56
SMA fiber-adapter ....................... 10, 47
SpectrAcq2 ................. 10, 12, 33, 42, 47
spectral range ..................................... 59
SR510 ......................... 10, 22, 28, 29, 47
SR530 ........................................... 22, 28
SR810 ............................... 10, 22, 28, 47
SR830 ............................... 10, 22, 28, 47
Stanford Research ...... 10, 12, 22, 28, 47
STATUS LED ....................... 24–25, 44
support leg .......................................... 16
SWB-AB ...................................... 10, 47
switchbox ..................................... 10, 47
Sync Output.................................. 35, 37
SynerJY® software ............................. 31
T
TEMP SET POINT control .......... 24–25
thermoelectric cooling10, 12, 14, 17, 20–
22, 24, 28, 41, 43–44, 47, 55, 60–63,
69
time constant ................................ 36–38
transient-decay experiment ................ 39
TRIAX ............................................... 15
troubleshooting .................................. 43
two-color detectors ........... 10, 47, 56, 59
U
ultraviolet light notice .......................... 4
Unpacking and Inspection .................... 9
V
vacuum pumps ................................... 43
voltage-selection card ........................ 24
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W warning notice ...................................... 4
warranty ............................................. 75
[Design Concept]
The HORIBA Group application images are collaged in the overall design.Beginning from a nano size element, the scale of the story develops all the way to the Earth with a gentle flow of the water.
3880 Park Avenue, Edison, New Jersey 08820-3012, USA