| 摘要 |
PROBLEM TO BE SOLVED: To provide a sensor device that enables an object to be finely discriminated more than before without inducing increase in costs and size.SOLUTION: An optical sensor includes a light source 11, a collimator lens 12, three light receivers (13, 13t and 15), a polarization filter 14, and a black box 16 that has the light source, the collimator lens, the three light receivers and the polarization filter housed. The light receiver 15 is configured to mainly receive surface regular reflection light, the light receiver 13 is configured to receive a P polarization component included in internal reflection light, and the light receiver 13t is configured to be arranged so as to receive light passing through the inside of a recording sheet. In this case, by detecting the amount of light of the P polarization component included in the internal reflection light, reflection light from the inside of the recording sheet can be highly accurately separated although conventionally the reflection light has been difficult to be separated due to a quite weak. Further, the amount of light passing through the inside of the recording sheet is configured to be detected. The reflection light from the inside of the recording sheet and the light passing through the inside of the recording sheet are configured to include information about an internal state of the recording sheet and a discrimination level of a sheet category can be enhanced up to a level of a brand, in which the enhancement up to the level of the brand has been conventionally difficult. |
