Abstract: A method of processing an optical element which has a substrate (110) and a layer system (120) applied to the substrate (110), wherein the layer system (120) in a starting condition has a plurality of volume defects (130), wherein the method includes at least partially filling at least one of the volume defects (130) with a filling material (140). Also disclosed is an associated method of manufacturing an optical element.

Abstract: The disclosure relates to an optical system of an illumination device of a microlithographic projection exposure apparatus, including at least one first light-conductance-increasing element having a plurality of diffractively or refractively beam-deflecting structures extending in a common first preferred direction the light-conductance-increasing element having an optically uniaxial crystal material in such a way that the optical crystal axis of the crystal material is substantially parallel or substantially perpendicular to the first preferred direction.

Abstract: An optical element unit is provided comprising an optical element group; a housing receiving said optical element group and having an inner housing part and an exit end; and a purge unit connected to said housing and providing a purge medium to said inner housing part. The optical element group comprises an ultimate optical element. The ultimate optical element is located at the exit end of housing and separates the inner housing part from an environment external to the housing. The ultimate optical element and the housing define a sealing gap. The purge unit provides purge medium to the sealing gap to prevent intrusion of contaminants into the inner housing part.

Abstract: A method of processing an optical element which has a substrate (110) and a layer system (120) applied to the substrate (110), wherein the layer system (120) in a starting condition has a plurality of volume defects (130), wherein the method includes at least partially filling at least one of the volume defects (130) with a filling material (140). Also disclosed is an associated method of manufacturing an optical element.

Abstract: An optical element unit is provided comprising an optical element group; a housing receiving said optical element group and having an inner housing part and an exit end; and a purge unit connected to said housing and providing a purge medium to said inner housing part. The optical element group comprises an ultimate optical element. The ultimate optical element is located at the exit end of housing and separates the inner housing part from an environment external to the housing. The ultimate optical element and the housing define a sealing gap. The purge unit provides purge medium to the sealing gap to prevent intrusion of contaminants into the inner housing part.

Abstract: The disclosure relates to an optical system of an illumination device of a microlithographic projection exposure apparatus, comprising at least one first light-conductance-increasing element having a plurality of diffractively or refractively beam-deflecting structures extending in a common first preferred direction the light-conductance-increasing element having an optically uniaxial crystal material in such a way that the optical crystal axis of the crystal material is substantially parallel or substantially perpendicular to the first preferred direction.

Abstract: The invention relates to a projection exposure system for microlithography, said system comprising an illumination device for generating a projection light, and a projection objective comprising a plurality of optical elements such as lenses (L5) and enabling a reticle that can be arranged in an object plane of the projection objective to be imaged onto a light-sensitive surface (26) that can be arranged in an image plane of the projection objective and is applied to a carrier (30). The inventive system is also provided with an immersion device between an image-side last optical element (L5) of the projection objective and the light-sensitive surface (26), for introducing an immersion liquid (34) into an immersion chamber (50). Said immersion device comprises means (44; 66) which can prevent the appearance of gas bubbles (48) in the immersion liquid (34), affecting the imaging quality, and/or can remove existing gas bubbles (48). Said means can be, for example, an ultrasound source (66) or a degasifier (44).

Abstract: A system for purifying purge gases for an optical system, in particular for a projection objective for microlithography for the fabrication of semiconductor components, wherein the optical system has at least one optical element in a housing with a purge gas passing through the housing. Contaminating substances which settle on surfaces of the at least one optical element in the projection objective are filtered out by photochemical means.

Abstract: In a system for flushing at least one internal space of an objective, in particular an exposure projection objective for semiconductor lithography, flushing is performed by mixing at least two inert gasses in such a way that the refractive index resulting therefrom corresponds at least approximately to the refractive index of air.

Abstract: In a system for flushing at least one internal space of an objective, in particular an exposure projection objective for semiconductor lithography, flushing is performed by mixing at least two inert gasses in such a way that the refractive index resulting therefrom corresponds at least approximately to the refractive index of air.