Patent ID: 7247834

Claim:
A photoelectric sensor for detecting the presence/absence of an object in a plurality of detection areas where a plurality of light-emitting areas of a light-emitting device and a single light-receiving area of a light-receiving device are overlapped with each other, the photoelectric sensor comprising: a power supply unit for outputting a plurality of different values of driving current to the light-emitting device; and a control unit for outputting a plurality of different control signals to the power supply unit so as to make the power supply unit output said plurality of values of driving current, wherein during a period of outputting one of said plurality of control signals, the control unit determines whether or not an output level of said light-receiving device is equal to or larger than a reference value, and if the output level is determined to be equal to or larger than the reference value, the control unit determines that an object is present in one of the detection areas where one of the light-emitting areas and the light-receiving area are overlapped with each other and outputs a digital or analog detection signal.