OPTICAL SYSTEM OF A MICROLITHOGRAPHIC PROJECTION EXPOSURE APPARATUS

摘要

The invention concerns an optical system of a microlithographic projection exposure apparatus. To permit comparatively flexible and fast influencing of intensity distribution and/or the polarization state, an optical system according to the invention comprises at least one layer system (120, 200) which is at least one-side bounded by a lens or a mirror, wherein said layer system (120, 200) is an interference layer system of several layers and has at least one liquid or gaseous layer portion (123, 220) whose maximum thickness is at a maximum 1 micrometer (µm), and a manipulator (105) for manipulation of the thickness profile of said layer portion (123, 220).