05488204 is referenced by 1203 patents and cites 4 patents.

A proximity sensor system includes a touch-sensor pad with a sensor matrix array having a characteristic capacitance on 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 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. Noise reduction and background level setting techniques inherently available in the architecture are employed. A conductive paintbrush-type stylus is used to produce paint-like strokes on a display associated with the touch-sensor pad.

Title
Paintbrush stylus for capacitive touch sensor pad
Application Number
895934
Publication Number
5488204
Application Date
October 17, 1994
Publication Date
January 30, 1996
Inventor
Timothy P Allen
Los Gatos
CA, US
Ralph Wolf
Palo Alto
CA, US
Carver A Mead
Pasadena
CA, US
Agent
D Alessandro & Ritchie
Assignee
Synaptics Incorporated
CA, US
IPC
G08C 21/00
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