Patent attributes
Light emitted from light-projecting elements constituted by LEDs (light-emitting diodes) or the like is transmitted to a light-projecting optical system of a sensor head portion through an optical fiber cable and projected from the light-projecting optical system onto an object. The light projected onto the object is reflected on the object. The reflected light is made incident on a light-receiving optical system. The light incident on the light-receiving optical system is led to a light-receiving element. The light-receiving element detects the incident light and generates a light-receiving signal based on the quantity of the detected light. The light-receiving signal generated by the light-receiving element is transmitted to a signal processing control portion of a main body portion through a light-receiving circuit and an electric wire cable.
