2. CONTENTS
Introduction
Type of Night Vision
The Basics
Working of Night Vision
Night Vision Devices
Application
Advantage & Disadvantage
CONCLUSIONS
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3. INTRODUCTION
Night vision is the ability to see in low light conditions. like in
Moonless and cloudy night.
Humans have poor night vision compared to other animals.
With the proper night vision equipment, we can see a person
standing over 200 yards (183 m) away on a moonless, cloudy night.
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4. Type of night vision
There are two type of night vision
Thermal Imaging
Image Intensifier
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5. THE BASICs
In order to understand night-vision, it is important to
understand something about light.
The amount of energy in a light wave is related to its
wavelength : Shorter wavelength have higher energy.
Of visible light, violet has the most energy, and red has the
least.
Just next to the visible light spectrum is the infrared
spectrum
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6. 5
Infrared light can be split into three categories:-
Near–Infrared (Near-IR) :- Closest to visible light, near-infrared
has wavelengths that range from 0.7 to 1.3 microns.
Mid-Infrared (Mid-IR) :- Mid-infrared has wavelengths range
from 1.3 to 3 microns.
Thermal-Infrared (Thermal-IR) :- Occupying the largest part of
the infrared spectrum, it has wavelengths range from 3 - 30
microns.
7. WORKING OF NIGHT VISION
Image Intensifier :-
Night vision amplifies light to achieve better vision.
A conventional lens, captures ambient light.
The gathered light is sent to the image-intensifier tube.
The light energy released electron from the cathode and
accelerated.
These electrons enter micro channel plate and bounce
and generate more electron.
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8. 7
Thousands of other electrons to be released in each channel.
Original electrons collide with the channel, exciting atoms and
causing other electrons.
New electrons collide with other atoms, creating a chain.
9. 8 In image-intensifier tube, the electrons hit a screen.
The energy of the electrons release photons and create
green image on the screen.
The green phosphor image is viewed through another lens.
10. NIGHT VISION DEVICEs
Night vision devices are basically divided into three
categories
SCOPES
They are monocular normally.
handheld or mounted on a weapon.
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14. ADVANTAGES
No particular skill required
Accidents cases reduction
Detection of object in absolute darkness
Less affected by temperature variation
DISADVANTAGEs
The only disadvantage is that the Initial cost too high.
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15. CONCLUSIONS
Night vision is used to locate an object which is 200 yards
away even in moonless, cloudy night.
The main purpose of night-vision was to locate enemy
targets at night.
It is mainly used in military purpose as well as navigation,
surveillance and targeting.
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