PHOTO-ELECTRIC POSITIONING DEVICE

摘要

Photo-electric positioning device for adjustment to a very accurate position in the manufacture of micro-circuits in which the enlarged images of the three first reflecting references drawn on the object to the positioned are centered on second opaque reference marks engraved on a translucent plate, a modulator disk having two concentric tracks rotating on each side of the said opaque references transmitting an identification signal to photo-electric cells which automatically control the lateral displacement of the object to center correctly each image on the corresponding reference mark.