OPTICAL SENSOR DEVICE

PROBLEM TO BE SOLVED: To minimize the influence of distance fluctuation and detect the presence of an object or the surface state by providing a light shielding member arranged so that the light quantity to shield is reduced as the object to be detected becomes more distant in front of the light receiving surface of a light receiving part. SOLUTION: A light emitting element 11 is driven by a light emitting circuit 12, and incident to the detecting range of an object by a condenser lens 13. The reflected light from the detecting range of distances LS-LL is received by a light receiving element 14. The output of the light receiving element 14 is converted into electric signal by a light receiving circuit 15, and when a light receiving signal exceeding a prescribed level is present, an object detection signal is outputted. A light shielding member 16 is provided in front of the light receiving surface of the light receiving element 14, and it is arranged so that the light quantity to shield is large when the object to be detected is near, and the light quantity to shield is reduced as the object to be detected becomes more distant. Namely, the light shielding member 16 is arranged so as to shield the reflected light incident from the nearest distance Ls side of the detecting range and not to shield the light between the distance LM-LL. Thus, the fluctuation of light quantity can be reduced.