Microlithographic projection exposure apparatus

Abstract

The disclosure relates to a microlithographic projection exposure apparatus, such as are used for the production of large-scale integrated electrical circuits and other microstructured components. The disclosure relates in particular to coatings of optical elements in order to increase or reduce the reflectivity.

What is claimed is: 
     
         1 . An optical system, comprising:
 a first optical element,   a second optical element,   a first antireflection coating supported by the first optical element,   a second antireflection coating supported either by the first optical element or by the second optical element;   wherein:
 within a first incidence angle range, the first antireflection coating has a polarisation-dependent reflectivity which is greater for s-polarised light than for p-polarised light; 
 within a second incidence angle range, the second antireflection coating has a polarisation-dependent reflectivity which is less for s-polarised light than for p-polarised light; 
 the first and second antireflection coatings are arranged in a beam path of projection light so that their polarisation-dependent differences in reflectivity at least partially compensate each other; 
   
       and
 the optical system is a microlithographic optical system.