04851616 is referenced by 105 patents and cites 10 patents.

A touch screen input system for use with a display screen having a photo-active display surface including a controllable sweeping beam. The system includes at least one photo-detector in combination with detection circuitry for continuously registering the position of the beam in the display surface. A pointer is adapted to reflect light from the beam to the photo-detector to provide a latch signal which is used to hold a signal identifying display screen location corresponding to pointer means location.

Title
Touch screen input system
Application Number
6/816065
Publication Number
4851616
Application Date
January 3, 1966
Publication Date
July 25, 1989
Inventor
H W Crowley
310 Parker, Newton, 02159
MA, US
R Langdon Wales
Moccasin Hill, Lincoln, 01773
MA, US
Agent
Wolf Greenfield & Sacks
IPC
G08C 21/00
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