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Night Vison Goggles

How Night Vision Devices Work

The Aviation Unit utilizes 4th Generation Technology.  All Night Vision Devices (NVD) consist of several main parts: an objective lens, an eyepiece, a power supply and an image intensifier tube (Photocathode Tube).  Night vision devices gather existing ambient light (starlight, moonlight or infra-red light) through the front lens. This light, which is made up of photons goes into a photocathode tube that changes the photons to electrons. The electrons are then amplified to a much greater number through an electrical and chemical process. The electrons are then hurled against a phosphorus screen that changes the amplified electrons back into visible light that you see through the eyepiece. The image will now be a clear green- hued amplified re-creation of the scene you were observing.  A Night Vision Device can be either a 1st, 2nd, 3rd or 4th generation unit. What this stands for is what type of image intensifier tube is used for that particular device; the image intensifier tube is the heart and soul of an NVD.

1st Generation

2nd Generation 3rd Generation 4th Generation
1st Generation 2nd Generation 3rd Generation 4th Generation
     
Night Vision Goggles Attached To Pilot's Helmet Helmet With Night Goggles Attached Flight Observer Gentry with Night Vision Goggles