ILLUMINATING OPTICAL APPARATUS, EXPOSURE APPARATUS AND DEVICE MANUFACTURING METHOD

摘要

Provided is an illuminating optical apparatus which can rapidly switch polarization statuses of illuminating light for a first region and a second region. The illuminating optical device for illuminating a surface (M) to be illuminated based on light from a light source (1) is arranged in an optical path between the light source and the surface to be illuminated. The illuminating optical apparatus is provided with a wavefront splitting optical integrator (9) having a plurality of wavefront splitting regions, and a polarization changing member (8) for changing the polarization status of at least a luminous flux which enters the first region of the wavefront splitting region of the optical integrator or a luminous flux which enters the second region of the wavefront splitting region of the optical integrator.