An illumination optics for EUV microlithography guides an illumination light bundle from a radiation source to an object field with an extension ratio between a longer field dimension and a shorter field dimension, where the ratio is considerably greater than 1. A field facet mirror has a plurality of field facets that set defined illumination conditions in the object field. A following optics downstream of the field facet mirror transmits the illumination light into the object field. The following optics includes a pupil facet mirror with a plurality of pupil facets. The field facets are in each case individually allocated to the pupil facets so that portions of the illumination light bundle impinging upon in each case one of the field facets are guided on to the object field via the associated pupil facet. The field facet mirror not only includes a plurality of basic illumination field facets which provide a basic illumination of the object field via associated basic illumination pupil facets, but also includes a plurality of correction illumination field facets which provide for a correction of the illumination of the object field via associated correction illumination pupil facets. The result is an illumination optics which allows unwanted variations of illumination parameters, for instance an illumination intensity distribution or an illumination angle distribution, to be corrected across the object field.