Imaging optics and projection exposure installation for microlithography with an imaging optics

An imaging optics, comprising:

• a plurality of mirrors configured to image an object field in an object plane into an image field in an image plane along an imaging light path, the plurality of mirrors comprising a first mirror in the imaging beam path after the object field, a last mirror in the imaging beam path before the image field, and a fourth to last mirror in the imaging beam path before the image field,
• wherein:
• a chief ray belongs to a central object field point;
• in an unfolded imaging beam path between the object plane and the image plane, an impingement point of the chief ray on a used region of each of the plurality of mirrors has a mirror spacing from the image plane;
• the mirror spacing of the first mirror is greater than the mirror spacing of the last mirror;
• the mirror spacing of the fourth to last mirror is greater than the mirror spacing of the first mirror;
• and
• chief rays that emanate from points of the object field that are spaced apart from another have a mutually diverging beam course, giving a negative back focus of the entrance pupil.