Cathy N Cavanaugh

US Patent:

61406368, Oct 31, 2000

Filed:

Mar 23, 1998

Appl. No.:

9/046942

Inventors:

Kirkpatrick William Norton - San Diego CA
Cathy Cavanaugh - San Diego CA

Assignee:

Hewlett-Packard Company - Palo Alto CA

International Classification:

G01D 534

US Classification:

25023118

Abstract:

An optical encoder provides absolute position information by inducing a position error in its output signal. The position error can be induced in the signal by shifting a slot in an encoder wheel or encoder strip relative to other slots in the encoder wheel. The position error is detected to identify an absolute position of the encoder wheel or the encoder strip.