Patent ID: 8487235
Filing Date: 2013-07-16
Classification: G01V

Abstract:
1. A photoelectric sensor for sensing a target at a predetermined location within first and second ranges that partly overlap, the sensor comprising: a light source that emits light; an output circuit including first and second photodetectors; a first receive lens positioned adjacent to the first photodetector; a second receive lens positioned adjacent to the second photodetector; a support structure for supporting each of the light source, the photodetectors, and the receive lenses in relation to one another, and that additionally includes at least one aperture; wherein the sensor is configured so that, if the target is at the predetermined location, then a first portion of light emitted by the light source is received by the first photodetector after being reflected off of the target and passing through the first receive lens, and a second portion of light emitted by the light source is received by the second photodetector after being reflected off of the target and passing through the second receive lens, and the output circuit produces a first output signal indicative of a sensed characteristic of the target based on signals generated by the first and the second photodetectors in response to the portions of light received by the photodetector; and wherein the sensor is additionally configured so that, if the target is at another location that is one of within the first range but not within the second range or within the second range but not within the first range, then the at least one aperture performs blocking of light so that the output circuit produces a second output signal that is only indicative of an additional portion light emitted by the light source that is received by one of the first and second photodetectors after being reflected off of the target and passing through one of the first and second receive lenses but not indicative of any further portion of light emitted by the light source that is received by the other of the photodetectors after being reflected off of the target.