Projection optical system, manufacturing method thereof, and projection exposure apparatus

摘要

A projection optical system forms an image of an object in a first plane onto a second plane. The projection optical system has an optical element group including at least one refractive member and plural reflective members, and a plurality of lens-barrel units holding the optical element group divided into a plurality of respective groupings. The reflective members are all held by a single lens-barrel unit of the plurality of lens-barrels units.