| 摘要 |
A catadioptric projection objective (100) for imaging an object field (OF) arranged in an object surface (OS) of the projection objective onto an image field (IF) arranged in an image surface (IS) of the projection objective has a plurality of optical elements aligned along a straight optical axis (OA) common to all optical elements of the projection objective. The optical elements include a mirror group (MG) having an object-side mirror group entry for receiving radiation coming from the object surface (OS) and an image-side mirror group exit for exiting radiation emerging from the mirror group exit towards the image surface (IS), where the mirror group includes at least one pupil mirror (M1) having a reflective pupil mirror surface positioned close to or at a pupil surface of the projection objective. A pupil mirror manipulator operatively connected to the pupil mirror and configured to vary the shape of the reflective surface of the pupil mirror allows for dynamically correcting imaging aberrations originating from lens heating, compaction and other radiation induced imaging aberrations occuring during operation of the projection objective. |
