Michael R Duff

US Patent:

7417624, Aug 26, 2008

Filed:

Feb 13, 2004

Appl. No.:

10/779359

Inventors:

Michael J. Duff - Fremont CA, US

International Classification:

G01D 11/28

US Classification:

345168, 345156, 345169, 345170, 345205, 341 22, 362 24, 362 26

Abstract:

Described is a zero-force key activation keyboard with individual key illumination. The keyboard includes a non-moving key for causing generation of an input signal when activated. The key has a depressed surface defining an approximately concave well with sides forming an open region sized to receive a tip of a finger. A light emitter positioned on one side of the well emits a beam of light across the open region to an opposite side of the well. A light detector is positioned on the opposite side of the well to receive the light beam and to signal activation of the key when the light beam is obstructed from being received by the light detector. Each key is illuminated from within the well. When the key is activated, its illumination color can change. Upon release, the illumination color returns immediately or gradually back to a previous color or unlighted state.