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1. NIGHT VISION
TECHNOLOGY
Night Vision Technology
saral K S
S7,EEE
Roll No 37
Presented by
Prejith Pavanan
S7 ECE
11419013

2. INTRODUCTION
• The word ‘Night vision’ itself means the ability
to see in low light conditions.
• Humans have poor night vision compared to
many other animals.
•Is it really possible to see in the dark night?
•We can see a person standing over 183m away
in the dark night.

3. HISTORY
•Pre 1940’s: Flares and spot lights were used for
operations at night.
•Due to the nature of these early night vision
devices (NVD), they gave away tactical positions.
•Military scientists began to think of ways to
improve night vision to gain a strategic advantage.

4. EARLY DEVELOPMENT
•The first night vision devices (NVD) were
created during World war-II.
•Functioned by placing an infrared filter over a
searchlight.
•Fighters would use special binoculars to see
using the light from the searchlights.
•Many problems came from this night vision
method.

5. A tank from
World War II
equipped
with a
search light
used for
night
combat.

6. HOW DOES IT WORK?
•The night vision is possible because of two
approaches:
(1) Sufficient spectral range
(2) Sufficient intensity range
•Two technologies are used for night vision:
(1)Thermal Imaging
(2)Image Enhancement

7. •Infrared light is used to visualize the things in
the dark.
•The amount of energy in a light wave is related
to its wavelength:
Shorter wavelengths 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.

8. Infrared light can be split into three categories:
•Near-infrared (near-IR) –
Closest to visible light, near-IR has wavelengths that range
0.7 to 1.3 micron.
•Mid-infrared (mid-IR) –
Mid-IR has wavelengths ranging from
1.3 to 3 microns.
Both near-IR and mid-IR are used by a variety of electronic
devices, including remote controls.
•Thermal-infrared (thermal-IR) –
Occupying the largest part of the infrared spectrum, thermal-
IR has wavelengths ranging from 3 microns to over 30
microns.

9. THERMAL IMAGING
•A special lens focuses the infrared light emitted
by all of the objects in view.
•The focused light is scanned by a phased array of
infrared-detector elements.
•The detector elements create a very detailed
temperature pattern called a thermogram.
•It only takes about one-thirtieth of a second for the
detector array to obtain the temperature
information to make the thermogram.

11. •This information is obtained from several
thousand points in the field of view of the detector
array.
•The thermogram created by the detector
elements is translated into electric impulses.
•The impulses are sent to a signal-processing unit,
a circuit board with a dedicated chip that
translates the information from the elements into
data for the display.

12. In day light In dark night
Using thermal imaging

13. IMAGE ENHANCEMENT

14. • An image-intensifier tube is used to collect and
amplify infrared and visible light.
•A conventional lens, called the objective lens,
captures ambient light and some near-infrared light.
• The gathered light is sent to the image-intensifier
tube.
•The image-intensifier tube has a photocathode,
which is used to convert the photons of light energy
into electrons.

15. •A Microscopic plate(MCP) is a tiny glass disk that
has millions of microscopic holes in it.
•The MCP is contained in a vacuum and has metal
electrodes on either side of the disc.
•When the electrons from the photo cathode hit the
first electrode of the MCP, they are accelerated into
the glass micro-channels by the 5,000-V bursts being
sent between the electrode pair.

16. •As electrons pass through the micro channels, they
cause thousands of other electrons to be released in
each channel using a process called cascaded
secondary emission.
•At the end of the image-intensifier tube, the
electrons hit a screen coated with phosphors.
•These electrons maintain their position in relation
to the channel they passed through, which provides
a perfect image since the electrons stay in the same
alignment as the original photons.

17. •The energy of the electrons causes the phosphors
to reach an excited state and release photons.
•These photons create the image on the screen.
•The green phosphor image is viewed through
another lens, called the ocular lens, which allows
you to magnify and focus the image.
•The NVD may be connected to a monitor to
display the image.

18. GENERATION- 0
• Created by US Army.
• Uses active infrared.
• A projection unit called IR illuminator is attached
with NVD.
• Use anode in conjunction with cathode to accelerate
the electrons.
• Problems : acceleration causes distortion of image
and reduction of the life of the tube.
• Duplicated by the hostile nations.

19. GENERATION- 1
• Uses passive infrared.
• Uses ambient light provided by the moon and the
stars.
• Doesn’t require a source of projected infrared light.
• Doesn’t work well on cloudy or moonless nights.
• Uses same image-intensifier tube technology as
Generation-0.
• Same problems as faced by the Generation-0.

20. GENERATION- 2
• Offer improved resolution and performance over
Generation-1 devices.
• Considerably more reliable.
• Able to see in extreme low light conditions due to
the addition of micro channel plate(MCP) to the
image-intensifier tube.
•The images are less distorted and brighter.

21. GENERATION- 3
• Currently used by the US Army.
• Better resolution and sensitivity.
• Photocathode is made up of Gallium Arsenide-efficient
of converting photons to electrons.
• MCP is coated with an ion barrier.
•Tube life is increased.

22. GENERATION- 4
• Known as filmless and gated technology.
• Shows significant improvement in both high- and
low-level light environments.
• No ion barrier in MCP.
• Reduced background noise.
• Enhances signal to noise ratio.
• Images are less distorted and brighter.

23. SCOPES
•Normally handheld or
mounted on a weapon,
scopes are monocular (one
eye-piece).
• Can not be worn like
goggles.
• It is good for when you
want to get a better look at a
specific object and then
return to normal viewing
conditions.

24. GOGGLES
•While goggles can be handheld,
they are most often worn on the
head.
• Goggles are binocular (two
eye-pieces) and may have a
single lens or stereo lens,
depending on the model.
• Goggles are excellent for
constant viewing, such as
moving around in a dark
building.

25. CAMERAS
•Cameras with night-vision
technology can
send the image to a
monitor for display or to
a VCR for recording.
• When night-vision
capability is desired in a
permanent location,
such as on a building.

26. CONTACT LENSES
Night vision contact lenses allow a person
to see clearly in low-light environments by
enhancing ambient light up to 200
percent.

27. Advantages
High sensitivity in low-light.
High speed imaging capability.
Able to detect people and vehicles
at at great distances.
Eliminates shadows and reveal identifying
lettering numbers and Objects.

28. Disadvantages
You can get blind if u look at something bright.
Blooming(state of anti-reflectiveness)-
night vision images gets partially distorted or
completely distorted.
Optical distortion during manufacturing.

29. APPLICATIONS
•Automobile
•Military
•Hunting
•Wildlife observation
•Surveillance
•Security
•Navigation
•Hidden-object detection
•Entertainment BMW's Night Vision with
Pedestrian Detection system
allows drivers to see what (or
who) is down the road -- even
on the darkest nights.

30. FUTURE SCOPE
•Future night vision goggles are being designed
not just to see at night but also to allow soldiers
to share images of what they see with other
soldiers who may be miles away.
•Scientists are experimenting with Panoramic
Night Vision Goggles (PNVGs) which double the
user's field of view to around 95 degrees by using
four 16 mm image intensifiers tubes, rather than
the more standard two 18 mm tubes. And lets
hope that more and more advancements will
be made in the field of night vision technologies.

31. CONCLUSION
• Many people are beginning to discover the
unique world that can be found after darkness
falls .
• The application within the scientific or the
civilian range is often prohibited by law.
• It is essential to combat terrorism which is a
major problem being faced by mankind.

32. REFERENCES
• Luria, S. M.; Kobus, D. A. (April 2013). Immediate Visibility After Red
and White Adaptation. Submarine Base, Groton, CT: Naval
Submarine Medical Research Laboratory (published 26 April 2013
• Luria, S. M.; Kobus, D. A. (July 2010). THE RELATIVE
EFFECTIVENESS OF RED AND WHITE LIGHT FOR SUBSEQUENT
DARK-ADAPTATION. Submarine Base, Groton, CT: Naval Submarine
Medical Research Laboratory Retrieved March 24, 2012
• Solovei, I.; Kreysing, M.; Lanctôt, C.; Kösem, S.; Peichl, L.; Cremer,
T.; et al. (April 16, 2011). "Nuclear Architecture of Rod
Photoreceptor Cells Adapts to Vision in Mammalian
Evolution". Cell 137 (2): 945–953.