JP2018013487A5

JP2018013487A5 -

Info

Publication number: JP2018013487A5
Application number: JP2017160483A
Authority: JP
Filing date: 2017-08-23
Publication date: 2018-05-17
Anticipated expiration: 2031-07-20

Description

本発明は、第１の観点からすると、第１の偏光方向の直線偏光を、シート状の対象物の表面に、該表面の法線方向に対して傾斜した入射方向から照射する照射系と、前記対象物で第１の方向に拡散反射された光の光路上に配置された第１の光検出器と、前記対象物で第２の方向に拡散反射された光の光路上に配置された第２の光検出器と、を備え、前記対象物で正反射される方向を正反射方向として、前記入射方向と前記対象物で前記第２の光検出器へ向けて反射される光の反射方向との成す角は、前記入射方向と前記正反射方向との成す角よりも小さく、かつ前記入射方向と前記対象物で前記第１の光検出器へ向けて反射される光の反射方向との成す角よりも大きく、少なくとも前記第１の光検出器及び前記第２の光検出器のいずれかと前記対象物との間の光路上に、前記第１の偏光方向に直交する第２の偏光方向の直線偏光成分を分離させる光学素子が配置されている光学センサである。 From the first viewpoint, the present invention irradiates the surface of the sheet-like object with linearly polarized light in the first polarization direction from an incident direction inclined with respect to the normal direction of the surface; A first photodetector arranged on an optical path of light diffusely reflected in the first direction by the object; and an optical path of light diffusely reflected by the object in a second direction. A second photodetector, and a direction of regular reflection by the object as a regular reflection direction, and reflection of light reflected toward the second photodetector by the incident direction and the object. The angle formed by the direction is smaller than the angle formed by the incident direction and the regular reflection direction, and the incident direction and the reflection direction of light reflected by the object toward the first photodetector. greater than angle between the front and at least either said first photodetector and said second photodetector The optical path between the object, a first optical sensor in which the optical element is arranged to separate the linearly polarized light component in the second polarization direction perpendicular to the polarization direction of the.

Claims

An irradiation system for irradiating the surface of a sheet-like object with linearly polarized light in a first polarization direction from an incident direction inclined with respect to the normal direction of the surface;
A first photodetector arranged on an optical path of light diffusely reflected in the first direction by the object;
A second photodetector arranged on the optical path of the light diffusely reflected in the second direction by the object,
The angle formed between the incident direction and the reflection direction of the light reflected toward the second photodetector by the object is defined as the incident direction, where the direction regularly reflected by the object is a regular reflection direction. Smaller than an angle formed by the regular reflection direction and larger than an angle formed by the incident direction and a reflection direction of light reflected by the object toward the first photodetector,
A linearly polarized light component having a second polarization direction orthogonal to the first polarization direction is provided on an optical path between at least one of the first photodetector and the second photodetector and the object. An optical sensor in which an optical element to be separated is arranged.

The optical sensor of claim 1, prior Symbol optical element on the optical path, characterized in that the that are located between the first of said object and light detector.

The optical sensor according to claim 1 or 2, characterized in that it is arranged before Symbol optical element on an optical path between the object and the second photodetector.

The plurality of photodetectors further includes a third photodetector disposed on an optical path of light diffusely reflected in a third direction sandwiched between the first and second directions,
The optical sensor according to claim 1 or 3, wherein the optical element is not arranged on the optical path between the front Symbol the object and the third photodetector.

The first optical detector, an optical sensor according to claim 1 or 2, characterized in that disposed on the light path in the normal direction to diffuse reflected light on the surface of the object.

The processing unit for specifying the object based on the output of the first photodetector and the output of the second photodetector is provided. The optical sensor according to item.

The direction of regular reflection by the object is a regular reflection direction, and the angle formed by the incident direction and the reflection direction of light reflected by the object toward the second photodetector, and the incident direction and The angle formed by the reflection direction of the light reflected toward the third photodetector by the object is smaller than the angle formed by the incident direction and the regular reflection direction, and the incident direction and the object. 5. The optical sensor according to claim 4 , wherein the angle is greater than an angle formed by a reflection direction of light reflected toward the first photodetector.

The angle formed by the incident direction and the reflection direction of the light reflected by the object toward the third photodetector is defined as the incident direction, where the direction of regular reflection by the object is a regular reflection direction. It is smaller than an angle formed by the object with the regular reflection direction and larger than an angle formed by the incident direction and a reflection direction of light reflected by the object toward the first photodetector. The optical sensor according to claim 4.

The illumination system, an optical sensor according to any one of claims 1-8, characterized in that it comprises a light source and a light path changing element for bending the optical path of the light beam in the incident direction from the light source.

The optical sensor according to any one of claims 1 to 9, characterized in that it comprises an optical path changing element for bending the optical path of light reflected by the object in the direction toward the at least one of said photodetectors.

The illumination system, an optical sensor according to any one of claims 1 to 10, characterized in that it comprises a surface-emitting laser.

In an image forming apparatus for forming an image on a recording medium,
An image forming apparatus comprising the optical sensor according to any one of claims 1 to 11, the object of the recording medium.

The image forming apparatus according to claim 12 , further comprising an adjusting device that identifies a brand of the recording medium based on an output of the optical sensor and adjusts an image forming condition according to the identified brand.