Photosensor employing optical guide posts to detect an object in the path

摘要

A plurality of optical guide paths are built in a guide path plate. A plurality of optical guide posts are erected on the guide path plate so that each may oppose to one end of the corresponding optical guide path. The other end of at least one of the optical guide paths is optically connected to a light projecting portion, and the other end of at least another of the optical guide paths is optically connected to a light receiving portion. A part to-be-sensed which is movable is located between the distal ends of the optical guide posts whose base ends are connected to the corresponding optical guide paths. The presence of the part to-be-sensed is detected in such a way that the part to-be-sensed interrupts or transmits light which passes between the distal ends of the optical guide posts.