This document discusses night vision technology, including its working principles and applications. It describes two types of night vision - image intensifiers and thermal imaging. Image intensifiers work by amplifying available light so that more electrons are produced, creating a visible image. Thermal imaging detects infrared radiation emitted by all objects based on their temperature to generate images without visible light. The document also covers the four generations of night vision devices and their uses in military surveillance, wildlife observation, search and rescue operations, and security.

1. Deprt. Of Electrical and Electronics Engineering

2. INTRODUCTION
TYPES OF NIGHT VISION
WORKING PRINCIPLE
IMAGE INTENSIFIER
THERMAL IMAGING
NIGHT VISION DEVICES
GENERATIONS
APPLICATIONS
CONCLUSION

3.  Night vision technology allows one to see in darkness.
 It is mainly developed for military surveillance.
 We can see a person standing over 180 m distance in a
moonless and cloudy night.
 It plays a key role in search and rescue operations.

4. Biological night vision:
 Molecules in the rods of the eye undergo a change in shape
according to the light.
 Molecules in the human rods is insensitive to the light
Technical night vision:
 Image intensifier
 Thermal Imaging

5. Image Intensifier:

6. Night vision amplifies light to a better vision.
A convention lens will capture completely envelops the surrounding
light.
The gathered light is sent to the image intensifier-tube.
In each channel there release thousands of electrons.
Electrons collide with each other and produce more.
The new atoms again collide and creates a chain.
These electrons after hitting a screen will produce photons and crea
a green image.
This green phosphor image is viewed through lens

7.  In order to understand thermal imaging, it is important to
understand something about light.

8. Three Types of IR rays:
Near Infrared:
Closest to visible light, near – IR has wavelengths
that range from 0.7 to 1.3 microns.
Mid Infrared:
Mid – IR has wavelengths ranging from 1.3 to 3 microns.
Thermal Infrared:
Thermal infrared the largest part of the infrared spectrum,
thermal – IR has wavelengths ranging from 3 microns to over 30
microns.

9. All objects emit infrared energy a function as a
function of their temperature

10. All objects emit infrared energy a function as a function of their
temperature
A lens will focuses the infrared light.
The focused light is scanned and create temperature pattern
The pattern is translated into electric impulses.
The impulses sent to an electrical circuit board that translates the
information into the data to display
The signal processing unit sends the information and it appears in
different colors.
Generally thermal images are black and white in nature.

11. Night vision device can be split into three categories
 SCOPES
They are monocular normally
handheld or mounted on a
weapon
 GOGGLES
The night vision binocular and
worn on the head
 CAMERAS
Used for transmission or
recording images mostly if the
location is fixed

12.  Generation 1:
In 1950’s devices based on vacuum tube technology are
available.

13.  Generation 2:
The vacuum tubes are simplified to single
stage in 2nd generation.

14.  Generation 3:
 The third generation night vision devices advanced in using small
electronic circuits

15.  Generation 4:
In present generation the researches are being made to bring it
into the micro electron chips.

16. Military
surveillance
Wild life
observation

17. Hidden Object
Detection
Property
management-Security
surveillance

18.  In present scenario night vision the applications of night vision
technology is very essential to combat terrorism which is the major
problem faced by the mankind.
 After a long journey from 1950’s we have much developed night
vision technology but it is limited in use.
 It will yield good results in future if we use it in every field for
defensive purpose.