06188391 is referenced by 1260 patents and cites 8 patents.

By suitable use of screen-printed carbon ink patterning, combined with patterning of the solder-mask layer on the top (finger) surface, a compact capacitive touchpad pointing device has been realized using only a two-layer board as a substrate. The first layer, on the topside of the printed circuit board, combines both the horizontal and vertical sensor electrode traces. The second layer, located on the underside of the printed circuit board, is formed in the conventional manner by attaching the controller chip and/or related circuitry.

Title
Two-layer capacitive touchpad and method of making same
Application Number
9/112097
Publication Number
6188391 (B1)
Application Date
July 9, 1998
Publication Date
February 13, 2001
Inventor
William Andrew Cesarotti
San Francisco
CA, US
Richard Robert Schediwy
Union City
CA, US
Timothy Peter Allen
Santa Cruz
CA, US
Robert Leonard Malak
San Jose
CA, US
Joel Seely
Milpitas
CA, US
Agent
Malcolm B Wittenberg
US
Assignee
Synaptics
CA, US
IPC
G09G 5/00
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