OPTICAL SENSOR DEVICE

PROBLEM TO BE SOLVED: To provide an optical sensor device allowing miniaturization while maintaining reception performance.SOLUTION: The optical sensor device comprises: a light-emitting element 11 emitting a measuring beam by current from a pulse current source circuit 12; a photodiode 13 receiving the measuring beam from the light-emitting element 11; an AD converter 14 outputting a first signal according to a signal strength of the received measuring beam; a storage circuit 15 storing the first signal as a second signal; and a subtraction circuit 16 subtracting the second signal from the first signal to output the result as a third signal. In initial measurement, the AD converter 14 measures light other than from a reflection object at a second reception sensitivity obtained by lowering a first reception sensitivity, and causes the storage circuit 15 to store the measurement as crosstalk. In the measurement by which the measuring beam including reflection light from the reflection object is measured, the subtraction circuit 16 subtracts the second signal from the first signal outputted from the AD converter 14, and a multiplication circuit 17 performs multiplication by a multiplication value according to lowering degree of the second reception sensitivity, performs signal amplification and outputs the result as a received optical output signal.