Electronics: Battles by Starlight

The sentry nervously stares at the ink-dark night. Among the rustlings of leaves and insects he hears a harder, hostile sound. He raises his rifle and presses an eye to a rubber cup at the end of a tubular scope. Now blackness turns into an eerie green glow; the sentry can see trees, bushes, rocks. If an enemy patrol is creeping toward him, he can spot the moving figures with surprising ease.

So far, such scenes have been acted out only in practice, but the Army’s new night-seeing scope is proving so practical that it soon will be made in quantity for troops in the field. And once on active duty, the new sighting devices should prove to be a marked advance over the famed snooperscopes that were so useful in World War II. The trouble with the snooperscopes was that they needed their own light source —a searchlight that illuminated targets with an infra-red beam. That was invisible to the naked eye but could easily be seen by an enemy equipped with relatively simple detection devices. The snooperscope sniper often found himself a sitting duck, his, own infra-red searchlight pinpointing his position.

The Army’s new night peeper leaves no such signature. It needs only the faint light that comes from the moon, stars or sky glow, which is never entirely absent. This light, bouncing off targets, is focused on a semitransparent screen at the front end of an extremely sensitive electron tube. The screen is photoemissive—it gives off electrons when struck by the faintest light. These photoelectrons are then speeded up by high electrical charges so that when they hit a phosphor (luminescent) screen in the tube, they make a much brighter image. The process is repeated three times, until it produces a picture thousands of times brighter than the starlit target viewed by an unaided eye.

The night-light scopes have $18 million of development behind them, and they come in three sizes. The smallest, which fits on a rifle or can be used as a hand telescope” weighs only 51 lbs., including its 6-volt batteries. Larger, 20-lb. scopes with a wider field of view are meant for use with recoilless rifles or other crew-handled weapons. The biggest scopes weigh 40 lbs. and sit fatly on tripods. Through their wide-angle lenses, a commander can keep track of the stumbling confusion of a night battle. He can see his own forces along with the enemy’s, and hopefully send enlightened orders that will result in a starlit victory.