Patent ID: 6947120

Claim:
Illumination system, particularly for microlithography with wavelengths ≦ 193 nm, comprising: a primary light source; a first optical component; a second optical component; an image plane; and an exit pupil, wherein said first optical component transforms said primary light source into a plurality of secondary light sources that are imaged by said second optical component in said exit pupil, wherein said first optical component includes a first optical element having a plurality of first raster elements, that are imaged into said image plane producing a plurality of images being superimposed at least partially on a field in said image plane, wherein said second optical component, comprises a first optical system comprising at least a field mirror with positive optical power and a second optical system comprising at least a further field mirror with positive optical power, wherein said first optical system images said plurality of secondary light sources in a plane between said first optical system and said second optical system forming a plurality of tertiary light sources, and wherein said second optical system images said plurality of tertiary light sources in said exit pupil.