Copyright 2007. All rights reserved. Utah Gun Collectors Association.
&ldquo,Fight at Night!&rdquo,
U.S. Army Night Vision, 1945-1980
Darkness ended each day&rsquo,s battle for centuries.
An army able to see at night has a tremendous tactical advantage over an enemy enveloped in darkness.
From the collection of John S. displayed at the October, 2006 Utah Gun Collectors Association Gun Show.
First, we must review five very important terms:
1. Active vs. Passive night vision-
- Active systems depend on artificial illumination light of some sort- flares, electric lights, etc.
- Passive systems use available natural light from the moon, stars, or skyglow.
2. Visible Light vs. Invisible Light
- Visible light is what we can see naturally. However, light exists in different wave lengths at both ends of the spectrum as well as in the range of colors we can see naturally.
- There is invisible infrared light at one end of the spectrum and invisible ultraviolet light at the other end of the spectrum.
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