Patent · US Expired

Method and apparatus for operating a capacitive tactile keyboard

US5525980A · kind A · utility

32Cited by
4References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 21, 1993
Grant dateJun 11, 1996
Priority date
Expiry dateApr 21, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F3/044
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method and apparatus for determining a valid selection of a capacitance tactile keyboard as a function of a selection state and validation state of the keyboard. The selection state is determined from measured capacitive values of each key by during a first phase of a cycle. The validation state is determined from measured pressure on the keyboard, for certain key selection states only, during a second phase of the cycle.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.