Night vision goggles

Night vision goggles (NVG) are a type of eye-wear that allows one to see in the dark. They are most often used by the military.

Related Topics:
Dark - Military

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Night vision goggles are one of two types. Passive system night vision goggles pick up any light in the given area and amplify it several thousand times. Often times a dim star in the sky is sufficient to illuminate an entire field. This type is commonly used for war reporting, tinting the picture green. The color green is chosen because the human eye is most sensitive and able to discern the most shades in that color.

Related Topics:
Night vision - Goggles - Green

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The other common type of night vision is an agressive type system that projects infared light (the same type used by a remote control), and then bases the visualization off the light reflected back. It is essentially a passive flashlight, where the only way to see the illuminated area is through an image enhancer. This feature is commonly found on home video cameras, as it suits most consumer's needs for seeing in the dark. Interestingly enough, pointing a television remote control at this type of system is glaringly bright.

Related Topics:
Remote control - Video cameras - Television

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Another common type of night vision goggles are heat-sensing/infrared goggles. These show anything that emits normal heat radiation in the given area.

Related Topics:
Infrared - Heat - Radiation

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There are currently goggles that combine both of these technologies to create images that are almost as clear as day. In addition to goggles, night vision technology is also used in rifle scopes, security cameras, binoculars, etc.

Related Topics:
Rifle - Scope - Security cameras - Binoculars

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Night vision goggles work by the photoelectric effect. As a photon collides with a detector plate, multiple electrons are ejected from the metal that are then amplified by a series of electron ejections onto a phosphorus screen.

Related Topics:
Photoelectric effect - Photon - Electron - Phosphorus

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