| 摘要 |
<p>A photoelectric sensor includes: a phototransmitter (1) that outputs light toward a detection target region of an object (5): an optical receiver (2) that receives the light outputted from the phototransmitter (1); a signal processing unit (3) that outputs a signal indicating that the object (5) is detected in response to a decrease of an amount of light received by the optical receiver (2); and two optical filters (10R, 10B, 20R, 20B) that are provided between the phototransmitter (1) and the optical receiver (2) to transmit only pieces of light having specific characteristics, In the phototransmitter (1), two kinds of light having different characteristics and that do not interfere with each other are outputted from output regions in the light transmitting surface, one of the two optical filters (10R, 108. 20R, 20B) has a characteristic of transmitting only one of the two kinds of light and the other of the optical filters (10R, 10B, 20R, 20B) has a characteristic of transmitting only the other of the two kinds of light; the optical filters (10R, 10B, 20R, 20B) are disposed opposite to output regions of the pieces of light different from the pieces of light of a selecting target while located across a detection target region; and output directions of the two kinds of light are fixed such that whole surfaces of the optical filters (10R, 10B, 20R, 20B) corresponding to the characteristics are irradiated with the two kinds of light from the phototransmitter (1) when the optical filters (10R, 10B, 20R, 20B) are disposed in a light transmitting surface while located away from each other by a predetermined distance or more.</p> |
