| 摘要 |
The objective of the present invention is to provide a reflective photoelectric sensor for a confined area, which can precisely detect an object having a variable distance to a surface to be measured by widening a detection range and which has a simple configuration. The reflective photoelectric sensor for a confined area (1A) comprises a transmitting part (10) having a laser diode (11), and a receiving part (20) having a photo diode (21). In the transmitting part (10) and the receiving part (20), a cross angle between the optical axis of a transmitting beam and the optical axis of a receiving beam is set so that the transmitting part (10) radiates the transmitting beam toward an object detection confined area (S1 to S3) and the receiving part (20) receives the receiving beam by reflection light from an object (M) existing in the object detection confined area (S1 to S3). Also, the reflective photoelectric sensor determines whether there is the object (M) according to a light receiving level in the photo diode (21). A diffraction grid (13) for dividing the transmitting beam into multiple directional beams is arranged on the light path of the transmitting beam from the laser diode (11). |
