Patent ID: 8305558

Claim:
An illumination system, comprising: an illumination subunit, comprising: an EUV light source configured to generate an emission beam of linearly polarized EUV illumination light; and a polarization setting device configured to set a defined polarization of the EUV emission beam of the illumination subunit by at least one movement selected from the group consisting of a rotational movement of the illumination subunit and a translational movement of the illumination subunit; an illumination optics configured to guide the emission beam along an optical axis to illuminate an illumination field in a plane with the emission beam; a nearest deflecting EUV bundle-guiding component; and a scattering component configured to increase divergence of the emission beam, wherein: the illumination subunit can be rotated about a portion of the optical axis that is arranged downstream of the illumination subunit and extends up to the nearest deflecting EUV bundle-guiding component; the EUV light source and the scattering component are arranged to be rotated about a portion of the optical axis that is downstream of the scattering component and extends up to the nearest deflecting EUV bundle-guiding component; and the illumination system is configured to be used in a microlithographic projection exposure apparatus.