Night vision technology

IT IS VERY HELPFULL IN NIGHT IN THE FIELD OF SURVILLEANCE, MILITARY, LASER GUNS AND SO ON...

1. Night Vision Technology BY ASHUTOSH KUMAR

2. Content Introduction Basics Thermal Imaging Image Enhancement Generations Night Vision Devices Applications Advantages Disadvantages Conclusion

3. Introduction The word “Night vision” itself means the ability to see objects in low light conditions. Humans have poor night vision compared to many other animals. With the proper night vision equipment , we can see a person standing 200 yards (183 m) on a moonless or cloudy night.

4. 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. Just next to visible light spectrum is the infrared spectrum.

5. Infrared can be split into three categories: near-infrared Mid-infrared Thermal-infrared Infrared light is emitted by an object because of what is happening at atomic level.

6. Thermal Imaging A special lens focuses the infrared light emitted by all the objects in view. The focused light is scanned by a phased array of infrared detector elements. The detector element creates a very detailed temperature pattern called Thermogram. The thermogram created by detector elements is translated into electrical impulses. The impulses are sent to signal processing unit

7. The signal processing unit sends the information to display. The combination of all the impulses from all of the elements create the image.

8. Image Enhancement A conventional lens, called the objective lens captures ambient light and some near-infrared light. The gathered light is sent to image intensifier tube. The image intensifier tube consists of : Photocathode Micro Channel Plate (MCP) Phosphors coated screen

9. Fig : Image Enhancement

10. Generations Generation 0 : The earliest (1950’s) night vision products were based on image conversion , rather than intensification Generation 1 : Vacuum tube technology Full moon operation Amplification : 1,000 Operating life : 2,000 Hours

11. Fig : Generation 1 night vision device

12. Generation 2 : First Micro Channel Plate operation One-quarter moon operation Amplification : 20,000 Operating life : 2,500 Hours Generation 3 : Improved Micro Channel Plate & Photocathode Starlight operation Amplification : 40,000 Operating life : 10,000 Hours

13. Fig : Generation 2 night vision device

14. Night Vision Devices Night vision devices are basically divided into three categories: Scopes : They are monocular normally handheld or mounted on a weapon.

15. Goggles : They are binocular and worn on the head. Cameras : Used for transmission and recording.

16. Applications Military Wildlife observation Hunting Surveillance Security Hidden object detection

17. Advantages Distant vision is possible. Detection of objects in absolute darkness. Less affected by temperature variations.

18. Disadvantages The image has low contrast and poor resolution. Do not see the target through transparent obstacles. High cost

19. Conclusion Today in the 21 st century we have come a long way in the development of night vision technology, from the early 1940s. In present scenario the applications of night vision technology is very essential to combat terrorism which is a major problem being faced by mankind.

20. Thank you