05982304 is referenced by 143 patents and cites 9 patents.

A piezoelectric keyswitch for providing tactile response comprises a bimorphic piezoelectric element anchored at its edge, and a keypad mounted on the bimorphic piezoelectric element spaced from the anchored edge so that depression of the keypad flexes the element to generate an electrical signal. A drive circuit responds to the electrical signal to provide a drive signal to bend the piezoelectric element to provide upward tactile feedback to the keypad.

Title
Piezoelectric switch with tactile response
Application Number
8/823472
Publication Number
5982304
Application Date
March 24, 1997
Publication Date
November 9, 1999
Inventor
Jonathan Noble Betts
San Francisco
CA, US
Edwin Joseph Selker
Palo Alto
CA, US
Agent
John H Holcombe
James C Pintner
Assignee
International Business Machines Corporation
NY, US
IPC
H03M 11/00
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