how starlight technology works

8/2/2019 How Starlight Technology Works

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HOW STARLI GHT TECHNOLOGY W ORKS ( b y ATN N igh t V is ion )

Night vision devices gather existing ambient light (starlight, moonlight or infra-red light) through the front lens. This light,

which is made up of photons goes into a photocathode tube that changes the photons to electrons. The electrons are then

amplified to a much greater number through an electrical and chemical process. The electrons are then hurled against a

phosphorus screen that changes the amplified electrons back into visible light that you see through the eyepiece. The

image will now be a clear green-hued amplified re-creation of the scene you were observing.

1. Front Lens 4. High Voltage Power Supply

2. Photocathode 5. Phosphorus Screen

3. Microchannel plate 6. Eyepiece

FI RST, SECOND, THI RD AND FOURTH GENERATI ON NI GHT VISI ON

ATN Nigh t V is ion Dev ice can be either a 1st, 2nd, 3rd or 4th generation unit. What this stands for is what type of light

intensifier tube is used for that particular device The light intensifier tube is the heart and soul of any night vision device.

1s t genera t ion o f ATN Nigh t V is ion is currently the most popular type of night vision in the

world. Utilizing the basic principles described earlier, a 1st generation will amplify the existing light

several thousand times letting you clearly see in the dark. These units provide a bright and sharp

image at a low cost, which is perfect, whether you are boating, observing wildlife, or providing

security for your home. You may notice the following when you are looking through a 1st gen unit

A slight high-pitched whine when the unit is on.

The image you see may be slightly blurry around the edges. This is known as Geometric Distortion.

When you turn a 1st gen off it may glow green for some time.

These are inherent characteristics of a 1st gen and are normal.

2nd genera t ion o f ATN Nigh t V is ion is primarily used by law enforcement or for professional

applications. This is because the cost of a 2nd gen unit is approximately $500.00 to $1000.00

more then a 1st gen. The main difference between a 1st and a 2nd generation unit is the addition

of a micro-channel plate, commonly referred to as a MCP. The MCP works as an electron amplifier

and is placed directly behind the photocathode. The MCP consists of millions of short parallel glass

tubes. When the electrons pass through these short tubes, thousands more electrons are released. This extra process

allows 2nd generation units to amplify the light many more times then 1st generation giving you a brighter and sharper

image.

3rd genera t ion ATN Nigh t V is ion By adding a sensitive chemical, gallium arsenide to the

photocathode a brighter and sharper image was achieved over 2nd generation. An ion barrier film

was also added to increase tube life. Gen. 3 provides the user with good to excellent low light

performance.



4th Genera t ion / Gated F i lm less tubes f rom ATN Corp :

4th generation / Gated Filmless technology represents the biggest technological breakthrough in

image intensification of the past 10 years. By removing the ion barrier film and "Gating" the

system Gen 4 demonstrates substantial increases in target detection range and resolution,

particularly at extremely low light levels.

The use of filmless technology and auto-gated power supply in ATN 4th generation image intensifiers result in:

Up to 100% improvement in photoresponse.

Superb performance in extremely low light level (better S/N and EBI)

At least triple high light level resolution (a minimum of 36 lp/mm compared to 12 lp/mm)

With significant improvement in contrast level and in performance under all light conditions, 4th generation represents

the top of the line performance in the night vision market. Note: The term 4th generation is used/accepted among Night

Vision manufactures to describe gated filmless tubes. However, this designation is widely debated and is currently

referred to as Filmless & Gated image intensifiers by the US Military.

ATN Gen 4 Night Vision technology improves night operational effectiveness

for military users of night vision goggles and other night vision devices. The

filmless MCP provides a higher signal-to-noise ratio than Gen 3, resulting in

better image quality (less scintillation) under low-light conditions. The gated

power supply further improves image resolution under high light conditions,

and the reduced halo minimizes interference from bright light sources. These

improvements also substantially increase the detection range of the systems.

Gen 3

Omni IVGen 4 Night Vision

%

Improvement

Photoresponse (�A/Im) 1800 1800 -

Signal-to-Noise Ratio 21.0

25.0(ground) 20% Higher

26.0(air) 24% Higher

Resolution(lp/mm) 64 64 -

Halo(mm) 1.25 0.75 40% smaller

Reliability(hours) 10,000 10,000 -

RANGE I MPROVEMENT Relat ive d i r ec t ion ranges

PVS-7 System

Overcast Starlight Conditions (-1x10E-5 tc)

Vehicle Size Target, 30% Contrast



Gen 2 SuperGen 2Gen 3 OMNI

I and II

Gen 3 OMNI

III

Gen 3 OMNI

IVGen IV

Detection Range (m) 170 270 240 290 360 430

% Improvement

over Gen II0% 60% 40% 70% 110% 153%

ATN Gen I V N igh t V is ion techno logy is no t cur ren t ly ava i lab le f o r expor t .

Ni gh t V i s i on Gogg l es and Scopes w i t h XD-4 I m age I n t ens i f i e r s

The XD-4 is the top grade of the DEP I mage I n tens i f ie rs . With the introduction of the XD-4 technology a new European

Standard for low light imaging was born providing unprecedented performance in Night Vision applications.

The XD-4 Image Intensifiers perform extremely well in all environmental

conditions. Its wide spectral sensitivity range ensures that a perfect picture is

obtained regardless of the user's environment (foliage, on water, snow, desert,

rocky and barren land) or light conditions (down to heavily overcast starlight).

The XD-4 Image Intensifiers provide as well a superb image under verydynamic light conditions.

The basis for the unique performance of the XD-4 is the technology used by DEP. This has resulted in greatly improved

performance parameters that are crucial for good observation, such as the Signal-to-Noise Ratio (SNR), the Modulation

Transfer Function (MTF) and Resolution under all circumstances. Add to this the very long lifetime throughout its

complete luminance dynamic range and you will be convinced of its unique performance.

The performance parameters of the XD-4 Image Intensifier are listed in the

table below. Highlights of the XD-4 specification are the typical SNR of 24, the

resolution of 64 lp/mm and over and - very important - the high MTF at low and

intermediate spatial frequencies. The latter gives the image its sharpness and

contrast.



It goes without saying that the XD-4 tubes can be supplied in every common mechanical construction including inverting

and non-inverting fibre-optic output, which also means that users have the opportunity to upgrade the performance of

existing Night Vision Equipment via a drop-in XD-4 Image Intensifier.

Technical specifications of XD-4 technology image intensifiers available in ATN Night Vision devices:

Resolution Minimal Typical Maximal UNIT

Limiting resolution

Type I 55 58 lp/mm

Type II 60 64 lp/mm

Modulation Transfer Function:

2.5 lp/mm 92 %

7.5 lp/mm 80 %

15 lp/mm 58 %

25 lp/mm 38 %

30 lp/mm 30 %

Signal to Noise Minimal Typical Maximal UNIT

Signal to noise (@108�lx) 20 24

Other Technical Data Minimal Typical Maximal UNIT

Phosphor: P20*

MTTF (to S/N=12) 15.000 hrs

Gain at 2.10-5 lx 30.000/p 50.000/p cd/m2/lx

Max. Output Brightness 2 17 cd/m2/lx

E.B.I. 0.15 0.25 lx

Output uniformity at 2850K 2:01 3:01

Weight(18mm) 80 95 grams

Shock 500 g

Luminous sensitivity at 2850K 600 700 uA/lm

Radiant sensitivity at 800nm 50 60 mA/W

Radiant sensitivity at 850nm 40 50 mA/W

DEP Image Intensifiers with XR-5 Technology

As a result of sustained and continuing product development, DEP is proud to introduce the latest, innovative XR5 Image

Intensifier with unprecedented performance for any environment and any circumstance.

The XR5 Image Intensifier, successor to the well-known and successful XD-4 Image Intensifier, reveals even more detailsof the night and offers an eXtended Range (XR) capability thanks to its new technology.



Furthermore, the XR5 Image Intensifier enables the user to see even more

during a full 24-hour day/night operation. This is done by the use of a fully

integrated Auto-Gating unit, which controls the image not only during day-

night-day transitions but also during dynamic lighting conditions such as those

experienced, for example, in night operations in urban areas. In practice, this

means no blooming to hinder your mission but dependable imagery throughout.

In addition, the halo is the smallest on the market.

The XR5 Image Intensifier from DEP represents the new European standard for Night Vision and is available in a variety

of inverting and non-inverting 18 mm formats.

The new XR5 is your best choice to maintain your combat effectiveness under all circumstances.

Technical specifications of XR5 technology image intensifiers:

Resolution Minimal Typical Maximal UNIT

Limiting resolution 64 70 lp/mm

Modulation Transfer Function:

2.5 lp/mm 93 %

7.5 lp/mm 82 %

15 lp/mm 67 %

25 lp/mm 46 %

30 lp/mm 35 %

Signal to Noise Minimal Typical Maximal UNIT

Signal to noise (@108�lx) 25 28

Luminance dynamic range Minimal Typical Maximal UNIT

Auto-Gating and Automatic Brightness Control 1.0E-06 5.0E+04 lux

Other Technical Data Minimal Typical Maximal UNIT

Phosphor: P20*

Reliability 15.000 hrs

Gain at 2E-05 lux 30.000/p 50.000/p cd/m2/lx

Max. Output Brightness 2 17 cd/m2

E.B.I. 0.25 ulx

Luminous sensitivity at 2850K 700 800 uA/lm

Radiant sensitivity at 800nm 65 78 mA/WRadiant sensitivity at 850nm 50 65 mA/W

Input voltage 2 3.7 volt

Input current 35 mA

Output uniformity at 2850K 1.8:1 3:01

Weight (18mm) 80 95 g

Shock 500 g



NI GHT VISI ON I NFRA-RED I LLUMI NATORS

All Starlight scopes need some light to amplify. This means that if you were in complete darkness

you could not see. Due to this we have a built in infra-red illuminator (IRI) on all of our scopes.

Basically what an IRI does is throw out a beam of infra-red light that is near invisible to the naked

eye but your NVD can see it. This allows you to use your scope even in total darkness. The IRI

works like a flashlight and the distance you can see with it will be limited. We do use the most

powerful eye-safe illuminator on the market. This allows our IRI to extend out to 100 yards

However, because of the power at a short distance the IRI may cover only 40-60% of the viewing area.

HOW FAR CAN YOU SEE WI TH NI GHT VISI ON SCOPE

There are many different variables that can effect the distance that you can see with a

Night Vision device. First, what are you trying to see? Are you looking for another boat

on the water or are you looking for a rabbit in the woods? The larger the object the

easier it is too see. Plus, are you trying to see details (what we call recognition range)

or are you just trying to see if something is there or maybe you will just see

movement but won't be able to 100% determine who or what it is. This is called

detection range. Second. Another variable is lighting conditions. The more ambient

light you have (starlight, moonlight, infrared light) the better and further you will be

able to see You can always see further on a night where the moon and stars are out

then if it is cloudy and overcast. We typically state that you can tell the difference

between a male and a female or a dog and a deer at about 75 to 100 yards. However,

if you were looking across an open field and there was a half moon out you could see

a barn or a house 500 yards away. Remember, that the purpose of a Night Vision

Device is to see in the dark not necessarily a long ways like a binocular or spotting

scope.

BLACK SPOTS ON THE SCREEN

As you look through a night vision device you may notice black spots on the screen. A NVD is similar

to a television screen and attracts dust and dirt. Typically these spots can be cleaned. However, this

may also be a spot in the tube itself. This is normal. Most tubes will have some spots in them. These

black spots will not affect the performance or reliability of the night vision device.

source: http://www.opticsplanet.com/info/how-atn-night-vision-technology-works.shtml, 02/17/12

how starlight technology works

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