Illumination device for use in micro-lithographic projection lighting system for illuminating reticule, has depolarizer arranged around rotational axis and partially causing effective depolarization of linearly polarized light

摘要

The device has a depolarizer that partially causes an effective depolarization of linearly polarized light impinged on the depolarizer while connecting with a light mixing system in a light propagation direction (L). Optically effective light emission surfaces (312, 321) of the depolarizer are formed as the non-planar surface. The depolarizer is rotatably arranged around a rotational axis. The rotational axis runs perpendicular to an optical axis. The depolarizer is formed from two partial elements (310, 320) with a complementary thickness profile. An independent claim is also included for a micro-lithographic projection lighting method.