An exposure method for use in an apparatus for projecting a pattern formed on a mask onto a photosensitive substrate through a projection optical system, comprises the steps of providing a mask bearing a pattern of which width gradually varies in a reference direction on the mask transferring the pattern...http://www.google.com/patents/US4908656?utm_source=gb-gplus-sharePatent US4908656 - Method of dimension measurement for a pattern formed by exposure apparatus, and method for setting exposure conditions and for inspecting exposure precision
