| 摘要 |
PROBLEM TO BE SOLVED: To provide a reflection type photoelectric sensor of a small size having a wide range of directivity, precluded from being malfunctioned by a factor such as water, and capable of preventing a high-reflecting object located in a distant place from being detected erroneously. SOLUTION: This reflection type photoelectric sensor is provided with the first light projection means for projecting light toward a detecting object, the second light projection means for projecting light toward the detecting object while arranging the first photoreception means for receiving reflected light of the light from the first light projection means to overlap respectively a light projection area and a photoreception area in a prescribed detection area to constitute the first light projection and reception means, and the second light projection and reception means constituted of the second photoreception means for receiving reflected light thereof. The second light projection means and the second photoreception means are provided not to overlap the light projection area and the photoreception area of the second light projection and reception means in a portion of a near-distance side in the detection area and to overlap those in a portion of a long-distant side, and a determination means generates a detection output when a value provided by subtracting an output of the second photoreception means from an output of the first photoreception means reaches a prescribed threshold value. COPYRIGHT: (C)2005,JPO&NCIPI |
