Apparatus and method of detecting positional relationship using a weighted coefficient

摘要

A device for detecting a relative positional relationship between first and second objects is disclosed. The device includes light source for projecting light to the first and second objects; photodetecting system for detecting light from one of the first and second objects illuminated by the light source system, the photodetecting system having a light receiving surface and producing a signal corresponding to the light intensity at each point on the light receiving surface; and position detecting system for detecting the relative position of the first and second objects, on the basis of signals from the photodetecting system, wherein the position detecting system is arranged to adjust signals corresponding to different points on the light receiving surface of the photodetecting system, by using different weight coefficients and to detect the relative position of the first and second objects on the basis of the adjusted signals.