Mark detecting method and apparatus usable, for example, in a semiconductor exposure apparatus such as a stepper for printing a pattern of a reticle upon a semiconductor wafer, for detecting, by using an image sensor, an alignment mark provided on a reticle or wafer for alignment of the same. Plural...http://www.google.fr/patents/US4962423?utm_source=gb-gplus-shareBrevet US4962423 - Mark detecting method and apparatus
