Patent ID: 6919561
Filing Date: 2005-07-19
Classification: G01D

Abstract:
1. A diffraction laser encoder apparatus for positional and movement information measurement of a target having a diffraction grating made thereon, said apparatus comprising: a laser light source for generating a source beam; a polarization beam splitter assembly comprising a polarization beam splitter for receiving said source beam for splitting a P-polarization component and an S-polarization component of said source beam into parallel and offset beams; a focusing lens assembly comprising a focusing lens for focusing said P-polarization component and said S-polarization component beams onto said target diffraction grating and returning diffracted P-polarization and diffracted S-polarization beams back into said polarization beam splitter for generating a detector beam coaxially containing said diffracted P-polarization and said diffracted S-polarization beams; and a detector assembly for receiving said detector beam for electrical processing and analysis for resolving into said positional and movement information.