04542375 is referenced by 148 patents and cites 14 patents.

A touch sensitive device is arranged with substantially parallel surfaces inside which light from a synchronized source, such as a CRT, can become trapped by total internal reflection. The screen is fitted with photodetectors which respond to the entrapment of light within the surfaces. The device is compliant so that a touch of the device at a particular point will cause an inward deflection of the surface at that point. The deflection causes light to become entrapped within the surface by total internal reflection thus making it possible, by comparing the photodetector output with the CRT raster position, to determine the exact surface position of the touch.

Title
Deformable touch sensitive surface
Application Number
6/347877
Publication Number
4542375
Application Date
February 11, 1982
Publication Date
September 17, 1985
Inventor
Peter S Kubik
South Plainfield
NJ, US
Harold G Alles
Bridgewater
NJ, US
Agent
David H Tannenbaum
Assignee
AT&T Bell Laboratories
NJ, US
IPC
G09G 1/00
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