OPTICAL GAUGING APPARATUS

摘要

This invention relates to an optical gauging apparatus utilizing a light projected toward an object to be gauged and reflected on the object to gauge a distance to the object or an amount of change occurring in the object. The gauging apparatus comprises light projecting means adapted to project two light beams from first and second light sources or split from the light of a single light source toward the object so that these two light beams provide the object with respective different luminance characteristics thereon, light receiving means adapted to receive the light reflected on the object, and a signal processor adapted to calculate a ratio of different luminances for said two light beams from output of said light receiving means and thereby to output an information on the gauged result.