Magnification: is simply the degree to which the object is enlarged. With a 7×35 binocular, for example, the object appears to be seven times closer than without the aid of a binocular. The number immediately following the "x" is the diameter in millimeters of the objective (front) lens. A 10×50 binocular, therefore, has a 10 times magnification with a 50mm objective lens.
Field of View: The field of view is the width, measured in degrees or feet, of the viewing area you would see at 1,000 yards.
Bright Source or Over-Light Protection: An electronic circuit that turns the power to the night vision device down or off when it is exposed to bright light (such as automobile headlights). This protects the image intensifier and extends its life. The device will recover and resume normal operation in 1-2 minutes.
EyePiece Focus: Used to match your night vision scope or binocular to your specific eyesight.
Image Intensifier Or Intensifier Tube: The active component in a night vision system that amplifies light and presents a usable image.
Infrared (IR) Illuminator: Provides a light source for the system to amplify, yielding enhanced images in very low light conditions such as caves where no ambient light is available for amplification.
Objective Lens: Collects all available light and focuses it on the image intensifier. It also provides image magnification.
Phosphor Screen: Positioned at the back of the intensifier tube, the green phosphor screen renders a visible night vision image. The human eye is most sensitive to green contrasts.
Photocathode: Converts light (photon energy) into electrons (electrical energy) which are then amplified in the intensifier. The objective lens focuses available light on the photoelectric surface of the photocathode, which is excited and passes electrons within the tube.
Resolution: A measure of the ability to render and display a detailed image. Image intensifier resolution remains constant and is expressed as the maximum number of line pairs per millimeter (LP/MM) that can be discerned when a black-and-white stripe pattern is focused on the photocathode.
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