The March, 1932 issue of Modern Mechanix described a nighttime gun sight that worked by throwing a very focused beam of light at the target. It was operated just like todays laser gun sights.
From Modern Mechanix …
A GUN sight for night firing, which may be attached to any revolver or pistol, has recently been patented and will soon be marketed by Ray Helm of Chicago, Ill.
The device, which has been especially designed for night police duty, consists of six small powerful condensers, an electric bulb, a special reflector, and a switch to make contact with small batteries.
When the gun is aimed and the switch pressed by the thumb of the gun hand the light indicates where the bullet will strike. The light carries for 250 feet and reflects on the target a light round spot about the size of a baseball at the point where the bullet will hit.
The sight is accurate up to its full range on large calibre arms, as the point blank range, for which no allowance need be made for gravity, is usually about this distance. On smaller arms it would be necessary to aim the light a few inches above the point for which the bullet is intended.
I was not able to locate the patent for this device. I believe this sight was one of the many snake-oil gun-related inventions published by Modern Mechanix. Even today, with our lithium batteries, high-performance LED lamps and relatively cheap high-quality optics, a device as small as the one pictured in the illustration above would be hard to construct.
[ Many thanks to Sven (Defence and Freedom) for emailing me the the info. ]