LIGHTING OPTICAL DEVICE, POLARIZATION STATUS DETECTOR,AND EXPOSURE SYSTEM AND EXPOSURE METHOD

摘要

A lighting optical device for lighting a surface (M) to be irradiated with a light from a light source (1), wherein a polarization status detecting means (50) for detecting the polarization status of a light flux advancing along a light path between the light source (1) and the surface (M) to be irradiated is provided, and the polarization status detecting means (50) comprises an optical element provided with an optical surface having a pyramid shape or a part-of-pyramid shape, and a light intensity detector for detecting the intensity of light traveling via the optical element.