Abstract: An interferometric measurement device for determining the birefringence in a transparent object comprises an interferometer with an input for an input light beam. At an output of the interferometer an object light beam passing through the object interferometrically superposes with a reference light beam not passing through the object. A positionally resolving measuring instrument determines at the interferometer output a distribution of phase differences between the object light beam and the reference light beam over the beam cross section of the beams. The measurement device further includes an instrument for modifying the polarization state of the input light beam.

Abstract: A projection exposure system for microlithography includes an illuminating system (2), a reflective reticle (5) and reduction objectives (71, 72). In the reduction objective (71, 72), a first beam splitter cube (3) is provided which superposes the illuminating beam path (100) and the imaging beam path (200). In order to obtain an almost telecentric entry at the reticle, optical elements (71) are provided between beam splitter cube (3) and the reflective reticle (5). Advantageously, the reduction objective is a catadioptric objective having a beam splitter cube (3) whose fourth unused side can be used for coupling in light. The illuminating beam path (100) can also be coupled in with a non-parallel beam splitter plate. The illuminating beam path is refractively corrected in passthrough to compensate for aberrations via the special configuration of the rear side of the beam splitter plate.

Abstract: A projection exposure system for microlithography includes an illuminating system (2), a reflective reticle (5) and reduction objectives (71, 72). In the reduction objective (71, 72), a first beam splitter cube (3) is provided which superposes the illuminating beam path (100) and the imaging beam path (200). In order to obtain an almost telecentric entry at the reticle, optical elements (71) are provided between beam splitter cube (3) and the reflective reticle (5). Advantageously, the reduction objective is a catadioptric objective having a beam splitter cube (3) whose fourth unused side can be used for coupling in light. The illuminating beam path (100) can also be coupled in with a non-parallel beam splitter plate. The illuminating beam path is refractively corrected in passthrough to compensate for aberrations via the special configuration of the rear side of the beam splitter plate.