Light pen

<hardware> An early pointing device which the user pointed at a raster-scanned display screen.

A photocell in the pen detected the flying spot of the raster scan.

The position of the spot at that instant, obtained from the scanning electronics, was made available to software as (x, y) co-ordinates.

< Previous Terms	Terms Containing light pen	Next Terms >
lifted domain LIGHT light client light-emitting diode light-emitting resistor	An Evolutionary System for On-line Programming DG/L Sketchpad Symbolic Mathematical Laboratory	light pipe light-weight Lightweight Directory Access Protocol light-weight process like kicking dead whales down the beach