07391861 is referenced by 64 patents and cites 58 patents.

A keypad in which output keystrokes are determined both from individual switch activation and from the combined activation of adjacent switches. The keypad has a substrate carrying an array of sense elements arranged to change state in response to keypad operation, a flexible cover disposed above the substrate and having an exposed surface defining an array of independent key regions, with combination key regions defined in interstices between adjacent independent key regions. Snap elements provide tactile feedback. Some versions have a touch-sensitive grid rather than a switch matrix. A method of dialing a telephone includes generating a corresponding sequence of numerals by transposing alpha character input into one of the numerals 2 through 9 according to standard telephone keypad letter-number correspondence

Title
Input devices and their use
Application Number
9/862948
Publication Number
7391861 (B2)
Application Date
May 22, 2001
Publication Date
June 24, 2008
Inventor
David H Levy
Cambridge
MA, US
Agent
Fish & Richardson P C
Assignee
Digit Wireless
MA, US
IPC
H04M 9/00
H04M 1/00
H04M 3/00
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