Patent ID: 8344895

Claim:
A photoelectric sensor that is provided with a light projecting unit projecting light toward a detection area and a light receiving unit receiving light from the detection area and generating a received light signal, the sensor being capable of obtaining a received light quantity based on the received light signal generated by the light receiving unit and comparing the received light quantity with a previously set threshold value, thereby detecting the presence of a workpiece in the detection area, the sensor comprising: a display unit that displays the received light quantity; an operation unit for instructing to execute a scaling function of assigning the received light quantity displayed in the display unit to a previously set target value; and a control unit that assigns a received light quantity when the instruction to execute the scaling function is accepted to the previously set target value, calculates a scaling adjustment ratio that is either a scale-up ratio or a scale-down ratio for assigning the received light quantity to the target value, and causes the display unit to display a received light quantity after the scaling obtained by scaling a subsequently obtained received light quantity up or down based on the scaling adjustment ratio, wherein the control unit assigns the received light quantity to a target value that is set to be greater than a display upper limit while executing the scaling function, and causes the display unit to display the display upper limit as the received light quantity after the scaling if the received light quantity after the scaling becomes greater than the display upper limit.