| 摘要 |
PROBLEM TO BE SOLVED: To provide a photoelectronic sensor and a failure detection method for the photoelectronic sensor, by which a failed state of an optical element can be accurately detected at a low cost in a space-saving manner regardless of the presence or absence of a shielding object.SOLUTION: The photoelectronic sensor for detecting the presence or absence of a shielding object 10 by shielding light with the shielding object 10 comprises: a projector 1 which projects a light beam; a first optical receiver 21 which is disposed so as to face the projector 1 and receives the light beam from the projector 1 when the shielding object 10 is not present between the projector 1 and the first optical receiver 21; a second optical receiver 22 which is disposed at a position where the light beam from the projector 1 reflected by the shielding object 10 is received when the shielding object 10 is present between the projector 1 and the first optical receiver 21; and a failure detection circuit 6 which detects a failure state of the projector 1, the first optical receiver 21 or the second optical receiver 22 when a light reception result of the first optical receiver 21 and a light reception result of the second optical receiver 22 are not in a complementary relation. |
