04264903 is referenced by 193 patents and cites 8 patents.

A control for use upon a solid panel, devoid of control shaft apertures, allows data entry by rotational positioning of a human member, such as one's finger, about a pattern of a plurality of interdigitated electrodes formed upon an interior surface of the panel. The position of the member varies the capacitance between adjacent ones of the electrodes, with position-decoding electronics energizing successive ones of the plurality of electrodes with successive phases of a master signal and recovering information relating the phase of the signal returned from the control to the position of the member. A light-emitting display may be positioned behind the panel to indicate the index of the control knob by a variable-length circular bar of light, a digitized display and the like.

Title
Capacitive touch control and display
Application Number
879368
Publication Number
4264903
Application Date
May 7, 1979
Publication Date
April 28, 1981
Inventor
John E Bigelow
Saratoga
NY, US
Agent
James C Davis
Marvin Snyder
Geoffrey H Krauss
Assignee
General Electric Company
NY, US
IPC
G06F 3/03
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