06002389 is referenced by 375 patents and cites 26 patents.

The present invention provides a touch pad which can detect a simply stylus using a change capacitance. The touch pad is made flexible, so that the stylus pressure compresses an insulating layer between a conductive reference layer and matrix of conductive traces. The compression causes a change in capacitance due to either the two capacitive conductive surfaces being closer to each other, or a variation of the dielectric value of the insulating layer due to the replacement of air in air gaps by the material of the insulating layer.

Title
Touch and pressure sensing method and apparatus
Application Number
637099
Publication Number
6002389
Application Date
September 23, 1997
Publication Date
December 14, 1999
Inventor
Bernard Kasser
Redwood City
CA, US
Agent
Townsend and Townsend and Crew
Assignee
Logitech
CA, US
IPC
G06K 11/16
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