An EUV projection lithography illumination optical unit guides illumination light toward an object field, the illumination optical unit comprising. The unit includes: a first facet mirror comprising a plurality of first monolithic facets; and a second facet mirror downstream of the first facet mirror in a beam path of the illumination light, the second facet mirror comprising a plurality of second facets, each second facet being configured to contribute to imaging a corresponding first monolithic facet of the first facet mirror into the object field via an illumination channel. Individual parts of the first monolithic facets are configured so that illumination light is guided from the individual parts of the first monolithic facets toward different target locations on the corresponding second facet of the second facet mirror.