The disclosure concerns a projection objective, which can include an object plane in which an object field is formed, an entry pupil, a mirrored entry pupil (RE) in a mirrored entry pupil plane obtained by mirroring the entry pupil (VE) at the object plane, an image plane, an optical axis, at least a first mirror and a second mirror. The projection objective can have a negative back focus of the entry pupil, and a principal ray originating from a central point of the object field and traversing the objective from the object plane to the image plane can intersect the optical axis in at least one point of intersection, wherein the geometric locations of all points of intersection lie between the image plane and the mirrored entry pupil plane.