Patent · US Expired

High visibility lightpipe in close proximity to function key

US5581251A · kind A · utility

15Cited by
5References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 13, 1995
Grant dateDec 3, 1996
Priority date
Expiry dateApr 13, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01H2221/03
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A lighted keyboard system which transmits light to the viewer via a clear rectangular column that uses the function key's guiding mechanism for support. The lightpipe emits light in a uniformly brilliant rectangle of light from a height above the surface of the keyboard. The lightpipe gathers light from an external light source which emits light at a wide viewing angle, and directs the emitted light along the center of the lightpipe to the emitting section. The beam of light is then diffused by the emitting section located at the top of the lightpipe, becoming a uniformly brilliant rectangle. The function key has a wide base which is used to guide the function key as it travels. This wide base never extends above the surface of the keyboard thereby maintaining all contacting surfaces between the guiding features and the function key below the surface of the keyboard. The function key has a key push center which is offset from the base of the function key. The associated guiding mechanism works in conjunction with the wide base to eliminate the moments produced when the function key is pressed at a point which is not over the base of the function key. The function key then moves smo…

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