Patent ID: 9217666
Filing Date: 2015-12-22
Classification: G01B,G01C,G01J,G01S,G08B

Abstract:
1. A photoelectric sensor comprising: a light projecting device configured to project a pulse of light from a light projecting element driven by a driving circuit; a light receiving element configured to receive the light projected from the light projecting device and to generate a light receiving signal according to an amount of the light received; a light receiving circuit configured to amplify the light receiving signal and to superimpose the light receiving signal on a reference level; an adjusting device having a variable resistor connected to a rotatable adjusting element and embedded in at least one of the driving circuit and the light receiving circuit, and configured to change a resistance value of the variable resistor according to a rotational position of the rotatable adjusting element so as to change the light receiving signal superimposed on a reference level by changing a characteristic of the at least one of the driving circuit and the light receiving circuit; an evaluator configured to generate a determination signal based on a comparison result between the light receiving signal superimposed on the reference level and a threshold value; a margin ratio calculator configured to calculate a ratio of an amount of the light receiving signal in the light receiving signal superimposed on the reference level and a difference between the threshold value and the reference level as a margin ratio; and a display device configured to display the margin ratio.