04680577 is referenced by 170 patents and cites 20 patents.

A multipurpose keyswitch for controlling cursor movement on a CRT display and for character entry includes a key cap that moves laterally to provide cursor control and that moves vertically for character entry. Sensors are coupled to the key cap for sensing the lateral movement of the key cap. Forward and backward movement of the key cap selects upward and downward movement of the cursor on the CRT display. Left and right movement of the key cap selects left and right movement of the cursor. Vertical movement of the key cap selects the entry of a character. The multipurpose keyswitch is advantageously positioned as one of the home keys of the keyboard.

Title
Multipurpose cursor control keyswitch
Application Number
555792
Publication Number
4680577
Application Date
April 18, 1986
Publication Date
July 14, 1987
Inventor
Eugene F Lynch
Portland
OR, US
Patrick J Franz
Colton
OR, US
David H Straayer
Colton
OR, US
Agent
Robert S Hulse
Allston L Jones
Assignee
Tektronix
OR, US
IPC
H01H 25/00
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