Abstract: A method for swapping an optical system, such as a DUV mirror, of a projection exposure apparatus, comprises: a) raising the optical system along a centre axis of the optical system so that mount struts of the optical system pass out of contact with frame struts of a frame carrying the optical system; b) rotating the optical system about the centre axis so that the mount struts are arranged between the frame struts; c) lowering the optical system along the centre axis; and d) shifting the optical system perpendicularly to the centre axis so that the optical system is moved out of a housing.

Abstract: A protective apparatus for lines between two components of a projection exposure apparatus for semiconductor lithography is firmly connected to the two components. the protective apparatus includes first and second partial regions which are configured to protect against mechanical damage to the lines. The first partial region is at least temporarily configured to mechanically decouple the first component from the second component.