Page 7 - CATALOG-INTERNATIONAL-DIGITAL-6-13-16

HOW NIGHT VISION WORKS
7
How
NIGHT
VISION
works
Phosphor Screen Tube
In Generation II and III systems, the objective lens collects minute particles of light (called photons) that you cannot see with your naked eye and focuses then
on the image intensi er. Inside the image intensi er tube, a photocathode absorbs this light energy and converts it into electrons. These electrons are then drawn through the micro channel plate that multiplies them thousands of times. When this highly intensi ed electron image strikes the phosphor screen, it causes the screen to emit light that you see. Since the phosphor screen emits this light in exactly the same pattern and degrees of intensity as the light that is collected by the objective lens, the bright night time image you see in the eyepiece corresponds precisely to the outside scene you are viewing.
Performance is the most important factor in night vision capabilities. Will a particular device allow you to see objects in near complete darkness? Night vision equipment offered by Night Vision Depot, Inc. will provide high quality images under extremely low light conditions such as cloudy, no moon nights. There are several terms used to compare the qualities of one tube to another. These speci cations, such as Resolution, Signal-to-noise, and Photocathode Response will determine how well a system will perform in these adverse conditions. Please see page 5 for detailed tube speci cations available.
Thin Disk