Patent ID: 9423279
Filing Date: 2016-08-23
CPC Classification: G01D,G05B

Claim Text:
1. An encoder comprising: tracks respectively having reflectors arranged along a measurement direction; a point light source configured to emit diffusion light to the tracks; one first light receiving array configured to receive light which is reflected at a track having an absolute pattern of said tracks and another first light receiving array configured to receive light which is reflected at a track having an absolute pattern of said tracks, wherein the one first light receiving array and the another first light receiving array are arranged across the point light source in a width direction substantially perpendicular to the measurement direction; a second light receiving array arranged in the width direction between the one first light receiving array and the point light source, and configured to receive light which is reflected at a track having a first incremental pattern of said tracks; and a third light receiving array arranged in the width direction between the another first light receiving array and the point light source, and configured to receive light which is reflected at a track having a second incremental pattern of said tracks, a pitch of which is longer than a pitch of the first incremental pattern.