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CHAPTER 1
IN TRODUCT IO N TO NIG HT V ISI O N
1.1 IN TRODUCT IO N
Night vision broadly refers to the ability to see in the dark or at night [15]. Night
vision technology developed that enables us to see in the dark. Night vision ability
could be present biologically or could be developed technologically. It uses the
combination of two approaches: Spectral range and Intensity range in sufficient
amounts. Animals have sharp night vision ability as compared to humans [18].
This is because of the presence of a layer of tissue in the eye called tapedum
lucidum (a Latin word meaning bright tapestry).It could be present just behind
the retina or sometimes within the retina. It contributes to superior night vision by
improving vision in low-light conditions as it reflects visible light back through
retina, thus, increasing the light available to photoreceptors. Tapedum lucidum
could be present in nocturnal animals especially carnivores that hunt at night.
Humans do not have this tissue. Night vision technology was originally developed
for military use; it has provided the United States with a strategic military
advantage in terms of the lives of people. Now, it is used for site security,
surveillance and search and rescue. The devices used in this technology have
grown through improvements in light amplifications technology. With proper
night vision equipments, one can see a person standing over 200 yards (183m)
away on a moonless, cloudy night.
1.2 APPROACHE S TO NIG HT V ISI O N
There are two types of approaches used in night vision technology. They are as
follows-
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1.2.1 SUFF IC IE NT SPECTRAL RA NG E:
The range up to which human eyes can see is limited only to a small portion of the
entire electromagnetic spectrum, called visible light. Spectral range techniques
allows human eye to be sensitive to those light that is otherwise invisible to
humans. It allows the viewer to take advantage of non-visible light sources of
electromagnetic spectrum such as infrared or ultraviolet radiations. Some of the
animals can see well in light other then visible light range like IR or UV radiations.
1.2.2 SUFF IC IE NT IN TE NSI TY RA NG E:
We know animals have better night vision than humans. This ability maybe
attributed to the fact that they may have larger eyeball, larger lens, larger optical
aperture, more rods than cones in retina [14], a tapedum lucidum, etc. Sufficient
intensity range is the capability to view with very small amount of light. Superior
intensity range can be achieved by means using technological concepts of image
intensification, thermal imaging or gain multiplication, CCD.
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CHAPTER 2
NIG HT V ISI O N DEV ICE S
2.1 IN TRODUCT IO N
Night vision equipments are ocular installments that produce images in near or
complete darkness. They maybe mounted aptly for particular purposes. Some
devices may also have more than one mounting options. These devices may
include image intensifier tube [17], different types of mounting systems, protective
and water-resilient housing, telescopic lenses, IR illuminators, etc. Example-the
AN/PVS-14[4] is a monocular night vision device used by military and by
civilians. They maybe mounted on the users head or helmet attachment, either as a
monocular device or maybe attached to the pair of binoculars, i.e., night vision
goggles, to enhance the degree of depth in visualizing.
Night vision devices were first used in World War II and were widely used during
the Vietnam War [3].The technology has gained wide recognition since the time it
has been developed. In the process of its growth, it has passed through severalgenerations, each presenting high and better performance and declining price.
Some Ex amples-
y Night vision goggles which have two eyepieces.y Scopes (i.e. monocular).y Night vision cameras, etc.
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2.2 WORK ING OF NIG HT V ISI O N DEV ICE S:
Night vision devices can work in different ways depending upon the methods used.
The common applications include night driving or flying, night security and
surveillance, wildlife observation, search and rescue, etc. Some of the common
methods are described below in Fig 2a:-
HOW NIG HT V ISI O N WORK S
LOW -L IG HT IM AGING THER M AL IM AGING NEAR IN FRARED ILLU MIN AT IO N
1. Image Intensification 1.C ooled-detector infrared 1. IR illumination
C ameras
2. U ncooled-detector infrared
C ameras
F ig 2a- C ategories of different night vision techniques used [3]
Basics of light - It is important to understand the basics of light in order to
understand the logic behind night vision. VIBGYOR constitute the visible light of
the electromagnetic spectrum as shown in Fig 2b. It stands for-
V-Violet infrared visible light ultravioletI-Indigo
B-BlueG-GreenY-Yellow ROYGBIVO-Orange R-Red
F ig 2b -E lectromagnetic spectrum [4]
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The amount of energy in light and wavelength are inversely related to each other.
Red color has longest wavelength, so, its energy is least. On the other hand, violet
color has highest energy and shortest wavelength. The neighbors of visible light
region are infrared and ultraviolet radiations. Infrared radiations are divided into three types-
y Near-infraredy M id-infraredy Thermal-infrared
Thermal infrared radiations are emitted by the objects whereas the two are
reflected from objects.
A tomic level :
Atoms are the smallest unit of matter. They are in continuous state of motion and
posses different energy levels. When external energy is supplied to them, they
move up to higher energy levels after getting excited.
Atoms contain sub-particles called-electrons, protons, and neutrons. Combination
of protons and neutrons are called nucleus. When energy is applied to atoms, its
electrons get energized and move up to higher levels from ground state. After
sometimes, they wish to come back to their original ground state, when they do so,
they emit photons with specific wavelength. These photons are in Thermal-
Infrared spectrum. The hotter the object, the shorter the wavelength of the infrared
photon it releases. If the object gets very hot, it may even eject out the photons in
visible spectrum; firstly glowing red, and then eventually white. [16]
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2.3THER M AL IM AGING :
This technology makes use of the upper portion of the infrared light spectrum,
which is emitted as heat by objects. It does not make use of ambient light at all.
The principle of operation is that all objects emit infrared energy as a function of
their temperature; i.e., hotter the object, the more radiations it emits [5].
W orking :
y The infrared light emitted by the objects is captured by a special lens.y The focused light is then scanned by a phased array of infrared-detector
elements. It is used to obtain temperature details to create a Thermo gram.y The Thermo gram is then translated in electrical impulses.y The impulses are sent to signal processing unit, that converts information to
data for display.
y The signal processing unit sends the information to the display where the
image is created.
y
The working is illustrated in Fig 2c and 2d
F ig 2c- Basic components of a T hermal-imaging system [5]
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F ig 2.d .a- E asy to see everything during day F ig 2.d .b -...b ut at night, you can see very little ...
F ig 2.d .c - T hermal imaging lets you see again
F ig 2.d- T hermal imaging [5]
There are two types of thermal imaging detectors -
1. C ooled detectors- They require cryogenic cooling to very cold temperatures
(below 200k).They can see a minute difference of 0.2F (0.1C) from more
than 1,000 ft (300 m) away, that is enough to see a person holding a gun. They
require semiconductor materials like mercury cadmium telluride (HgCd), etc,
in their designing. Cooled detector is shown in Fig 2e.
F ig 2e- C ooled Detector [5]
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T ab le 2.1 -Advantages and disad vantages of cooled detectors
Ad vantages D isad vantages y The highest possible thermal
sensitivity.
y Expensive to purchase and operate.
y Able to detect objects at great
distances.
y Limited cooler operating lifetime.
y Not affected by bright light sources. y May require several minutes to cool
down upon initiation.
y Able to perform high speed infrared
imaging.
y Bulky.
y Able to perform multi-spectral
infrared imaging.
y They are able to penetrate obscurants
like smoke, fog, and haze.
EXA M PLE S- Short-wave infrared cameras
M id-wave infrared cameras
Long-wave infrared camerasM ulti-spectral infrared cameras
2. U ncooled detector- Unlike cooled detectors, they are capable to operate at
or near room temperature. This is the most common type of thermal imaging
device. When infrared radiations from objects are focused onto this detector, it
causes the electrical properties of the detector material to change. These
changed values are compared to the original values, thus, creating an image.
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T ab le 2.2 -Advantages and disad vantages of uncooled detector
Advantages D isad vantages
y Relatively inexpensive y Less sensitive and has low picture
quality than cooled detectors.y High contrast in most night time
scenes .
y Cannot be used for multi-spectral and
high speed infrared applications .
y Easily detect objects.
y Not affected by bright light sources.
y Highly reliable.
EXA M PLE S- Uncooled thermal imaging camera (fixed mount) [2].
Uncooled thermal imaging camera (portable).
2.4 LOW -L IG HT IM AGING :
It is the most popularly used method for performing night vision operation. It
makes use of a special tube, called Image Intensifiers [17]. M ore recently, on-
chip gain multiplication CCD cameras have become popularized for
performing low-light security, surveillance and astronomical observation.
IM AG E IN TE NSI F IER TUBE - It is used to collect and amplify infrared and
visible light for better vision [6].
W orking :
y A conventional lens, called the objective lens captures the ambient light
and some near-infrared light.
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y The gathered light is sent to the image-intensifier tube; which is powered
by cells or batteries which generates a high voltage of about 5,000 volts.
y The image intensifier tube has a photocathode, which is used to convert
photons of light energy into electrons due to high electric field of
cathode.
y These electrons enter holes in micro channel plate. This plate has
millions of these microscopic holes. It is contained in a vacuum and has
metal electrodes on either side. These electrons on hitting the electrodes
cause the emission of thousands of other electrons.
y
This creates a dense cloud of electrons representing an intensified imageof original image.
y Finally, these electrons hit the phosphor screen. The energy of electrons
makes them to reach excited levels and make the phosphor screen to
glow. Generally, green light is used to view the image on the
photographic cameras or video devices. This color is used because
human eyes can differentiate more shades of green than any other color,
thus, providing better view.
y The working is illustrated in Fig 2f.
F ig 2f-Image E nhancement [6]
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T ab le 2.3 - Advantages and disad vantages of image intensifier
Advantages D isad vantages
y Excellent low-level light sensitivity. y Since, they are based on amplification,
thus, they require some light. So, this
cannot be used when there is no light.
y Enhanced visible imaging yielding the
best possible recognition and
identification performance.
y Inferior day-time performance when
compared to daylight-only methods.
y High resolution y Possibility of damage when viewing
bright sources under low-light
conditions.y Low-power and cost.
y Ability to identify people.
EXA M PLE S- Night vision goggles
Night vision pocket scopes
Intensified canon cameras
Intensified professional news cameras
2.5 NEAR IN FRARED ILLU MIN AT ION :
It is a popular and inexpensive method for performing night vision. In this method,
a device that is sensitive to invisible infrared radiations is used in combination with
an infrared illuminator [19] [20].
This method was popularized by Sony Night Shot Camcorder. This is because
camcorders CCD detector [2] was IR sensitive and infrared light source was
installed in the camcorder, so, infrared illumination was available to enhance
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otherwise low-light video scenes and produce reasonable image quality in low-
light situations.
This method can be in a variety of night vision application where by using video
motion detection and intelligent scenes analysis devices, a reliable low-light video
security system can be developed.
1. IR Illuminator- Several devices are used-y L aser type- These devices are based on infrared laser diode
that emits near infrared energy. They are most efficient
infrared illuminators.
y L ed type illuminator- These illuminators utilize an array of
infrared emitting LEDs.
T ab le 2.4 - Advantages and disad vantages of near infrared illumination
Advantages D isad vantages
y Lowest cost as compared to other
night vision techniques.
y Users of infrared illuminators can be
detected by others that have near-infrared viewing devices.
y Eliminates the variability of ambient
light.
y Eliminates shadows and reveal
identifying lettering, numbers and
objects.
y Able to perform facial identification.
y Able to perform high-speed video
capture.
y Capable of seeing through night time
fog, mist, rain and snowfall.
Ex amples- Wide area infrared laser illuminator [7]
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CHAPTER 3
G E NERAT IO NS
NVDs have been around for more than 40 years. They are categorized by
generations. Each considerable change in NVD technology establishes a new
generation. [8]
3.1 G E NERAT IO N 0:
The first night vision devices were introduced by the German army as early as
1939. They were based on image conversion, rather than image intensification.
They required a source of invisible infrared light mounted on the device to
illuminate the target area.
These devices were used in World War II and the Korean War. It used a projection unit, called IR illuminator to project a beam of infrared
light.
This beam gets reflected back from the object back to the lens of NVD.
It used both cathode and anode combined to accelerate electrons.
Draw b acks :
Acceleration of electrons distorted the image. Life of tube was decreased. It gets easily duplicated by other enemy nations.
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3.2 G E NERAT IO N 1:
First generation devices were introduced during Vietnam War.
They relied on ambient light of the moon and stars, instead of infrared lightsource, to enhance the amount of reflected infrared in atmosphere.
Generation 1 NVDs use the same image intensifier tube technology as
generation 0.
The NVDs have three image intensifier tubes in series. In the figure, the incoming light is collimated by fiber optic plate, then, they
impact the cathode which releases electrons which in turn strike the
phosphor screen where the green light is emitted.
The process is repeated three times and a total amplification of around
1000x is obtained [9]. The working is shown in Fig 3a.
F ig 3a - W orking of Gen 1 de v ices [9]
Draw b acks :
The image was clear at center but distorted at the edges. They do not work well on cloudy or moonless nights. Tube life was short. They were large in size and bulky.
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Ex amples - AN/PVS-2 Starlight scope.
Yukon Spartan NV monocular.
3.3 G E NERAT IO N 2:
In this generation, the features of image-intensifier tube were greatly improved.
This is due to the use of micro channel plate. [10]
It offered great resolution and high performance over generation 1 devices. They are more reliable. They improved size and image quality.
Figure shows the basic configuration. M CP consists of millions of microscopic hollow glass channels. When
electrons pass through these channels, then, under the influence of applied
voltage, several more electrons are released which strike the phosphor
screen.
The biggest gain of this generation is the ability to see in extremely low light
condition like moonless night. It gives less distortion and much brighter images. Light amplification of around 20,000 xs is possible. The M CP enables the development of handheld and helmet mounted
goggles. The working is shown in Fig 3b.
F ig 3b - W orking of Gen 2 de vices [10]
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Ex amples- AN/PVS-4
AN/PVS-5
3.4 G E NERAT IO N 3:
There were two substantial advancements seen in this generation devices.
It maintained the use of M CP but improvised it by making use of
photocathode made with gallium arsenide. It is very efficient in converting
photons to electrons. The gallium arsenide photocathode enabled detection of objects at greater
distances under much darker conditions.
It helped improving image resolution and sensitivity. The second was the use of ion-barrier film on the M CP. It increased the
operational life of the tube from around 2000 hours in generation 2 to 10,000
in generation 3.
In this generation, the light amplification was also increased to around
30,000-50,000x.
Ex amples - AN/PVS-7
AN/NVS-7
AN/PVS-10
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3.5 G E NERAT IO N 4:
Generation 4 is commonly known as Filmless and Gated Technology. This
generation NVDs have shown remarkable improvements in both low and high
level light atmosphere.
This generation devices presented substantial increase in target detection
range and resolution, especially in extreme low-light levels.
It marked the removal of the coating of ion-barrier in M CP. Hence, called
Filmless. Removing of this ion film allowed more electrons to reach the
amplification; hence, they were less distorted and brighter.
Another change, rather addition, was the use of automatic gated power
supply. This allowed NVD to respond to the fluctuating lightening
condition. This is because the photocathode voltage rapidly switched on and
off. Its utility could be understood with the help of the example- if a person
is using night vision goggles and somebody else turns on a bright light at
him. Then, he might become blind temporarily or sightless. But, here the
advantage of generation 4 devices is that it will rapidly and quickly gets
adjusted to this bright light and would not loose sight and still can see
objects. So, it automatically changes high light to low-light and vice-versa.
They use gallium arsenide photocathode. They are expensive to purchase. It provides at least triple high level resolution.
Draw b ack :
Decrease in the operational life of the tube.
Fig 3c shows the comparison among various generations.
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Generation 1 Generation 2
Generation 3 Generation 4
F ig 3c- C omparison of different generations [11]
3.6 KEY DEVELPO M E NT OF G E NERAT IO NS :
If we are using night vision devices to find a lost person, to locate boats or buoys
on the water, or to stargaze into the wilderness, we should prefer generation 3, as it
creates good quality images when there is very little ambient light. Generation 2
may be chosen in cases with higher level of ambient light [16].
y Generation 1( in 1960 s) :
Vacuum tube technology. Full moon operation. Amplification up to 1,000. Operating life of 2,000 hours.
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y Generation 2( in 1970 s) : Quarter moon operation. Amplification of micro channel plate. Amplification up to 20,000 Operating life of 2,500 hours. Improved resolution.
y Generation 3( in 1990 s) : Improved M CP and photocathode.
Use of gallium arsenide and ion-barrier. Star light operation. Amplification up to 40,000. Operating life of 10,000 hours. Enhancement in resolution and brightness.
y Generation 4(1990 s) :
Filmless and auto-gated power supply. No ion-barrier in M CP. Quickly responds to different lightening
conditions.
Images are less distorted and are brighter.
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CHAPTER 4
C haracteristics of Night V ision
Below are some of the aspects of night vision that one should be aware of when
using an image intensified night vision system.
T extures, L ight and Dark :
Objects that appear light during the day but have a dull surface may appear
darker, through the night vision unit, than objects that are dark during the
day but have a highly reflective surface. For example, a shiny dark colored
jacket may appear brighter than a light colored jacket with a dull surface.
F og and R ain :
Night vision is very responsive to reflective ambient light; therefore, the
light reflecting off of fog or heavy rain causes much more light to go toward
the night vision unit and may degrade its performance.
H oneycom b : Some faint hexagonal patterns may be observed on the image. It is the result
of the manufacturing process of the device.
B lack Spots :
A few black spots throughout the image area are also inherent characteristics
of all night vision technology. These spots will remain constant and should
not increase in size or number. See Fig 4a below showing an image with
black spots.
F ig 4a- Black spots [16]
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CHAPTER 5
OTHER TECH NOLO GI E S
5.1 ATN
WPTrepresents
a
new
standard
of
night
vision
[11]:
ATN has provided its customers with a new line of technology called WPT-
white phosphor technology as shown in Fig 5a.
Generally, in NVDs, the images appear green in color. But, studies reveal
that with the use of this technology, the images appear more natural in
black and white.
This technology has reported a better performance, more degree of
details, full moon similarity, distinguished shades of intensity between
white and black, better contrast.
M ost of its performance characteristics are equivalent or better then the
GaAs based image intensifier tubes.
People prefer this over the common green night vision.
It is available in systems like- ATN PVS 14/6015 Tactical M onocular FIITS-14 where WPT is optically fused with
Thermal Imaging
ATN M arsx6
Specifications :
Photocathode type : multi-alkali Image output : black-and-white image Tube life : 10000 hours Signal-to-noise ratio : 18-26
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STA NDARD NIG HT V ISI O N VIEW VIEW THROU G H WPT DEV ICE
F ig 5a- WPT de vices giving white view [11]
5.2 PA NOR MI C NIG HT V ISI O N G O GG LE S (P NVGS) :
The United States air force is experimenting with PNVGS in order to double
the field of view of the users to around 95 degrees by using four 16mm
Image Intensifier tubes; rather than 18mm tubes (two).
They are in use with A-10 Thunderbolt 11, AC-130U Spooky Aircrew , etc.
5.3 E NHA NCED NIG HT V ISI O N G O GG LE S (E NVG) :
It is also known as AN/PS Q -20.it was manufactured by ITT. It strives to combinethermal imaging with image intensification, as does the Northrop Grumman Fused
M ultispectral Weapon Sight.
5.4 LA SER RA NG E G ATED IM AGING :
It is another form used for night vision. It utilizes high powered pulsed light source
for illumination and imaging.
Range gating is a technique that controls laser pulses in collaboration with
the shutter speed of the cameras detector.
It is of two types-single shot and multi shot.
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CHAPTER 6
EQU IP M E NT S AND APPL ICAT IO NS
6.1 EQU IPM E NT S:
Night vision equipments can be split into broad categories-
Goggles- They come in two categories:- M onocular, that has a single lens or
stereo lens or they could be Binoculars having two lens or two eyepieces. It
depends upon the model or designer. They can be mounted on the head or
they also come as handheld. They are comfortable, portable and can be
efficiently used in case of constant viewing.
Example- AN/AVS-6 Vision Goggles [12]
Dual Sensor Night Vision Goggles (in Fig 6a)
F ig 6a- Dual Sensor Night V ision Goggles [12] F ig 6b -DARK IN VADER NVG [12]
Scopes- They come into two ways, i.e., mounted or handheld. They could be
mounted on a weapon. They are monocular in nature. They are best utilized
when one has to focus on a particular object for sometimes and then, resume
back to normal conditions.
Example- AN/PVS-12 Starlight scopes
DARK INVADER M ulti-purpose Pocket scopes (in Fig 6c)
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F ig 6c- DARK IN VADER Multi-purpose Pocket scope [11]
C ameras- With the use of cameras, we are able to get a display as it sends
images to monitor or to a VCR for recording. They are typically used when
and where night vision capabilities are desired in areas, like a building or
part of the equipment in a helicopter. They can also be used as a medium
where monocular or scopes can be attached on it. M any of the newly
developed camcorders have in-built night vision; like, Sony Night Shot
Camcorders, etc.
Example- Intensified Canon Cameras
Intensified Nikon Cameras
Intensified Removable Lens Camcorders
Low-Light CCD Cameras
F ig 6d- Stealth 301 Series Day/Night Video C amera [11]
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6.2 APPL ICAT IO NS :
F ig 6e- Soldier using DARK IN VADER NVG [11]
It has a variety of application. Some of the common applications are briefly
described below-
M ilitary Law enforcement Wildlife observation Hunting Camping Search and rescue operations Security Surveillance Navigation Hidden object detection An aid for night blindness
The first use of NVDs for which they were developed was for the usein military to locate targeted enemies during night time or in the dark
areas.
L aw enforcement has widely made use of this technology. It can be
used to discover items that have been hidden by criminals like money,
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bodies, etc. Also, with the help of Thermal Imaging technique,
changes made to areas like walls can be detected. Thus, it is quite
helpful in providing beneficial clues for solving cases.
NVDs can be useful in case of protection to the wildlife and keeping awatch on intruders. The concerned authorities can make use of this for
wildlife observation.
Also, people who are fond of hunting and camping at night can make
use of this technology.
Various organizations and also people at home, employee night vision
cameras, get them fitted for security purpose, to monitor the
surroundings.
Police use NVDs for sur veillance purposes. Through the use of
Thermal Imaging, it is possible to detect whether an area has been
disturbed, like, we can detect whether ground has been dugged up to
bury something or not. Thus, this is very beneficial to the police and
other detectives or private investigators [1].
Night vision goggles [8] have been especially praised by the pilots of
search and rescue teams of helicopters. They retain their ability to fly
safely under night conditions and can detect people suffering from one or
the other natural calamities like flood, earthquake, etc (in Fig 6e).
People who are suffering from the problem of night b lindness , i.e.
they are unable to see during night can surely be benefitted from the
use of NVDs. They can be useful in na vigation . By using NVDs, it becomes
convenient for the ships to pass through and find their way. It can
direct or assist the course of a ship or an aircraft and also protect them
from any possible mishappening.
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CHAPTER 7
FUTURE SCOPE
Working, analysis and improvements are being carried out to create better night
vision devices. Planning is carried out and future night vision goggles are being
designed not only to see clearly but also to allow soldiers in the army to share
images of what they see with other soldiers who maybe far away. Though, the idea
is accepted as feasible, but, the developers are facing some difficulties in
implementing it. But, it is assumed that it will form an integral feature of the next-
generation goggles. [13]
Generation-4 night vision devices as we know are also called as Filmless
because they have removed the ion-barrier film on the MCP. This film provided
greater operational life of the tube, but, with its removal, again Gen-4 NVDs have
low operational life tubes. This is its drawback. Work is also been carried out to
implement some technique by which the tube life can be increased.
M oreover, it is also being focused to provide the different varieties of NVDs atreasonable prices, as they are quite expensive.
Also, the concept of combining or merging the two techniques of Image
Intensification and Thermal Imaging could be of great use in future. Through this
idea, newer and positive features or strengths of both the techniques can be
combined like:-from Image Intensification, a sharp, clear, green-colored picture
can be obtained and from Infrared, we are capable to see under any type of environmental condition. This concept has been implemented in a device called
Enhanced Night Vision Goggles or ENVG but, it is in analog form. Efforts are
being made to transition it into a digitized version. It is assumed that by 2014, the
digital ENVG will be ready for sale .
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CHAPTER 8
CO NCLU SI O N
The report started with the basic knowledge of what is night vision? What is night
vision technology? M oving further light has been thrown on the principle working
of night vision devices with their examples. There are different generations of
night vision devices. Generation 0, marks the use of image conversion techniques.
It used infrared radiations to illuminate the targeted object. Generation 1, used
Image Intensification Techniques to see the objects in dark. It relied on ambient
light sources. It had low-level light sensitivity. Generation 2, marked the use of
micro channel plate ( M CP) which greatly enhanced the picture quality. M CP not
only accelerated the electrons but also multiplied them in number. Generation 3,
showed two great advancements. First, was the use of GaAs photocathode and
second was the ion-barrier film on M CP. It helped increasing the operational life of
the tube. Generation 4, also called the Filmless and Gated, removed the ion-
barrier film on M CP. This generation presented substantial improvements in target
detection range and resolution. It was suitable in fluctuating light conditions. After that, we discussed about the characteristics and other related technologies in the
field of night vision technology. M oving further, we saw the various equipments
that are used for night vision like-cameras, binoculars, monocular, goggles, scopes.
Lastly, we went through some of its interesting applications like-its use in military,
law enforcement, wildlife observation, navigation, etc. We ended with some
knowledge of the future scope of night vision devices.
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