Patent ID: 8786436

Claim:
A multiple optical axis photoelectric sensor comprising: a projector, an optical receiver, a plurality of optical axes between the projector and the optical receiver, at least one selecting circuit configured to sequentially validate the optical axes, a processor coupled to the at least one selecting circuit for conducting optical axis scan processing of the optical axes, an output for outputting a light state of the photoelectric sensor, and a variable update unit configured to update a first variable and a second variable according to every determination result of the optical axis scan processing, wherein the light state comprises a light entrance state and a light obstruction state, wherein the light state comprises the determination result of a detection area being in the light entrance state or the light obstruction state based on a result of the optical axis scan processing, wherein the first variable is updated while the determination result that the detection area is in the light entrance state is continuously made, and the second variable is updated according to the determination result that the detection area is in the light obstruction state.