Patent · US Expired

Multi-function key input device

US4885580A · kind A · utility

81Cited by
22References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 15, 1988
Grant dateDec 5, 1989
Priority date
Expiry dateMar 15, 2008

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S379/916
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A multi-function key input device having a touch panel serving as a key input means, which is operated separately according to different operational modes to display different symbols or matters with the aid of a central processing section, a memory section, a digital shift register and LCD drivers operating a liquid crystal device.

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