Illumination optical element for projection lithography

An illumination optical unit configured to illuminate an object field along an illumination light beam path, the illumination optical unit comprising:

• an optical rod, comprising:
• an end-side entrance area for illumination light;
• and
• an end-side exit area for the illumination light, the end-side exit area opposing the end-side entrance area;
• and
• a first element upstream of the optical rod in the illumination light beam path,
• wherein:
• the optical rod is configured so that, during use, the illumination light is mixed and homogenized at lateral walls of the optical rod by multiple instances of total internal reflection;
• and
• the first element is configured to specify an illumination over the end-side entrance area, of:
• i) a non-homogeneous illumination intensity;
• and ii) simultaneously, an illumination angle distribution.

An illumination optical unit configured to illuminate an object field along an illumination light beam path, the illumination optical unit comprising:

• an optical rod, comprising:
• an entrance area for illumination light;
• and
• an exit area for the illumination light, the end-side exit area opposing the entrance area;
• and
• a first element upstream of the optical rod in the illumination light beam path,
• wherein:
• the optical rod is configured so that, during use, the illumination light is mixed and homogenized at lateral walls of the optical rod by multiple instances of total internal reflection;
• and
• the first element is configured to specify an illumination over the entrance area, of i) a non-homogeneous illumination intensity;
• and ii) simultaneously, an illumination angle distribution.