Patent ID: 8942583
Filing Date: 2015-01-27
Classification: G03G

Abstract:
1. An optical sensor, comprising: an irradiating system which irradiates, toward a surface of a subject, a linearly polarized light in a first polarization direction from an incident direction which is slanted relative to a normal direction of the surface; a first photodetecting system including a first photodetector which is arranged on an optical path of a light which is specularly reflected from the subject; a second photodetecting system including an optical element which is arranged on an optical path of a light which is diffuse reflected from the subject within an incident face in the subject and which separates a linearly polarized component in a second polarizing direction which is orthogonal to the first polarization direction and a second photodetector which receives a light separated by the optical element; and a restricting member which is arranged on an optical path of an incident light with respect to at least one photodetector amongst the first photodetector and the second photodetector and which restricts a light receiving range in the at least one photodetector, wherein the restricting member includes a restricting part which is arranged on an optical path of a light which is incident onto the second photodetector, the restricting part has an opening with a shape which restricts a light receiving range in the second photodetector with resect to a direction (y) which is orthogonal to an incident face in the second photodetector, and in the opening of the restricting part, a length along the direction (y) which is orthogonal to the incident face in the second photodetector is shorter than that alone a direction (x) which is parallel to the incident face.