Illumination optical apparatus, exposure apparatus, and device manufacturing method

摘要

An illumination optical apparatus has a beam splitting member which splits an incident beam into a first light beam and a second light beam to form a first illumination region and a second illumination region, a first light-guide optical system which guides the first light beam to the first illumination region, and a second light-guide optical system which guides the second light beam to the second illumination region locate apart from the first illumination region.