Patent ID: 7582888

Claim:
A reflection type optical sensor, comprising: a light emitting unit having an optical axis; two light receiving units each having an optical axis and configured to sense light received from the light emitting unit; and a 1 ight receiving guide located adjacent each of the light receiving units, each of the light receiving guides having an optical light emitting axis, wherein the optical light emitting axes of the light receiving guides are spaced apart from each other along their length by a first distance, and the optical axes of the light receiving units are spaced apart from each other along their length by a second distance, wherein the first distance is less than the second distance such that the optical light emitting axes of the light receiving guides are closer together than are the optical axes of the light receiving units, wherein the light emitting unit and the two light receiving units are configured such that each of the optical axes of the light receiving units intersects the optical axis of the light emitting unit at a substantially identical predetermined angle, thereby detecting reflected light.