Surface position detecting system and device manufacturing method using the same

摘要

A detecting system for detecting positional information related to a surface of an object. The detecting system includes a variable pattern generator for projecting an arbitrary pattern image on the surface of the object, a light projecting optical system for projecting a pattern, defined by the variable pattern generator, to the surface of the object along an oblique direction, a light receiving optical system for directing light from an image of the pattern and a light receiving element for detecting the light directed by the light receiving optical system. Surface position information about the surface of the object is detected on the basis of the detection by the light receiving element.