Patent ID: 7193204
Filing Date: 2007-03-20
Classification: G01D

Abstract:
1. An optical encoder including: a sensor head including a substrate and beam divider, the beam divider including an optical wavefront dividing element, the substrate having a light source and first and second optical detectors disposed thereon; an encoder scale including first and second tracks, the encoder scale being disposed opposite the sensor head with the beam divider disposed therebetween such that a light beam emitted by the light source is incident on the wavefront dividing element, the wavefront dividing element being operative to divide the incident beam into first and second beams being substantially incident on the first and second tracks of the encoder scale respectively, light from the first beam being reflected and diffracted by the first track to the first optical detector, and light from the second beam being reflected and diffracted by the second track to the second optical detector; and a signal processor operative to interpret signals from the first and second detectors.