05648642 is referenced by 331 patents and cites 120 patents.

A proximity sensor system includes a sensor matrix array having a characteristic capacitance between horizontal and vertical conductors connected to sensor pads. The capacitance changes as a function of the proximity of an object or objects to the sensor matrix. The change in capacitance of each node in both the X and Y directions of the matrix due to the approach of an object is converted to a set of voltages in the X and Y directions. These voltages are processed by analog circuitry to develop electrical signals representative of the centroid of the profile of the object, i.e, its position in the X and Y dimensions. The profile of position may also be integrated to provide Z-axis (pressure) information.

Title
Object position detector
Application Number
895934
Publication Number
5648642
Application Date
October 25, 1994
Publication Date
July 15, 1997
Inventor
Stephen J Bisset
Los Altos
CA, US
Robert J Miller
San Jose
CA, US
Agent
D Alessandro & Ritchie
Assignee
Synaptics Incorporated
CA, US
IPC
G06F 3/033
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