Electric eye

Electric eye, or photoelectric cell, electronic device either producing current or allowing current to flow when light shines on it, used for controlling such devices as lights and burglar alarms, and for measuring light for photographic and video equipment. They react rapidly to light changes and respond to visible as well as invisible (infrared and ultraviolet) light waves. Phototubes, solar cells, and photoconductive cells are types of electric eyes.

See also: Electronics.