Night vision tech.pptx

7/28/2019 Night vision tech.pptx

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CONTENTS INTRODUCTION EARLY DEVELOPMENTWORKING OF NVT THERMAL IMAGING TYPES OF THERMAL IMAGING DEVICES IMAGE ENHANCEMENT

GENERATIONS CURRENT GENERATION NIGHT VISION EQUIPMENTSAPPLICATIONS

CONCLUSION


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INTRODUCTION Night vision is the ability to see in low light conditions.

Whether by biological or technological means, night vision is

made possible by a combination of two approaches: sufficientspectral range, and sufficient intensity range. Humans havepoor night vision compared to many animals.


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EARLY DEVELOPMENT The first night vision devices (NVD) were created

during WWII.

Functioned by placing an infrared filter over asearchlight.

Fighters would use special binoculars to see using thelight from the searchlights.

There were many disadvantages to using thesearchlights and flares.


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WORKING OF NVT IMAGE ENHANCEMENT:-Image intensification

technologies work on the principle of magnifying theamount of received photons from various natural

sources such as starlight or moonlight. Examples ofsuch technologies include night glasses and low lightcameras.

THERMAL IMAGING:-Thermal imaging technologies

work by detecting the temperature difference betweenthe background and the foreground objects.


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THERMAL IMAGING A special lens focuses the

infrared light emitted byobjects.

The focused light is then

scanned by phased array ofinfrared-detector.

The thermogram is thentranslated into electricalimpulses.

The impulses are sent to asignal-processingunit(S.P.U).

At last the (S.P.U) sendsinformation to the display.


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TYPES OF THERMAL IMAGING

DEVICES Un-cooled - This is the most common type of thermal-

imaging device. The infrared-detector elements arecontained in a unit that operates at room temperature. This

type of system is completely quiet, activates immediatelyand has the battery built right in.

Cryogenically cooled - More expensive and moresusceptible to damage from rugged use, these systems havethe elements sealed inside a container that cools them to

below 32 F (zero C). The advantage of such a system is theincredible resolution and sensitivity that result fromcooling the elements.


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IMAGE ENHANCEMENT Aobjective lens, captures ambient

light and near-infrared light from theobject.

The gathered light is sent to the image-intensifier tube.

Aphotocathode, which is used toconvert the photons of light energy intoelectrons.

As the electrons pass through thetube, multiplying the original numberof electrons by a factor of thousandsthrough the use of a microchannel

plate (MCP) in the tube. At the end of the image-intensifier tube,

the electrons hit a screen coated withphosphors.

The green phosphor image is viewedthrough another lens, called theocularlens,


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GENERATIONS GENERATION O:-

i. First created by U.S.Armyin early 1950s.

ii. These were based on image conversion rather than

intensification.iii. Used in World war II and Korean war.

GENERATION 1:-

i. Developed in 1960s .

ii. NVDs of this generation use ambient light provided bythe moon and stars.

iii. Used in Vietnam to carryout operations.

iv. Operating life of 2,000 hours.


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Cont. GENERATION 2:-

i. Developed in 1970s.

ii. First Micro Channel Plate(MCP) application.

iii. One-Quarter Moon Operation.

iv. Operating life:2,500hrs.

GENERATION 3:-

i. Developed in 1990s.ii. Improved MCP & Photocathode.

iii. Starlight operation.

iv. Operating life:10,000hrs.


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CURRENT GENERATION Generation 3 is currently used by the U.S. military.

However Generation 4 is under consideration, which

has overall improvement in both low and high-levellight environments and even less noisy thangeneration 3.


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NIGHT VISION EQUIPMENTS Scopes -

i. Normally handheld ormounted on a weapon.

ii. Scopesare monocular innature.

iii. Since scopes arehandheld, not wornlike goggles.


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cont. Goggles -

i. Goggles can be handheld,they are most often wornon the head.

ii. Gogglesare binocular (two eye-

pieces) and may have asingle lens or stereo lens.


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Cont. Cameras -

i. Cameras with NVTcan send the image toa monitor for displayor to a VCR forrecording.

ii. It is desired in apermanent location,such as on a buildingfor Security.


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APPLICATIONS Military

Hunting

Wildlife observation

Surveillance

Security

Navigation

Hidden-object detection


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CONCLUSION

In conclusion I believe that is wonderful how

something originally designed for destruction, cannow help people on an every-day basis.

This is truly amazing technology.


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THANKS FOR PATIENTS!!!


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ANY QUERY???

Date post:	14-Apr-2018
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Night vision tech.pptx

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