To provide wavefront information without detaching a projection lens system from a tool by arranging the lens system in such a way as to receive electromagnetic radiation that has passed through a reticle having a plurality of lattices of different periods and orientations while the reticle is placed on a reticle stage.

A reticle 14 having lattices 16 is arranged at a focal distance fF from a field lens 12 while a reticle lens 20 is arranged at a focal distance f from the reticle 14. The reticle lens 20, an aperture 22, and a wafer lens 24 constitute a projection lens system 18. The projection lens system 18 is used to form an image of the lattices 16 on the reticle 14 on a nominal focal plane 28 positioned at a distance (f) from the wafer lens 24. A first plane 26 is positioned at a given distance from the nominal focal plane 28, while a second plane 30 is positioned at another given distance from the nominal focal plane 28. As a result, wavefront information can be mapped, based on the intensity information for a variety of lattices obtained from a plurality of detection planes.