Patent ID: 8970951
Filing Date: 2015-03-03
Classification: G02B,G03F

Abstract:
1. A mask inspection microscope for generating an image of the structure of a reticle, arranged in an object plane, in a field plane of the mask inspection microscope, comprising a light source that emits projection light along at least one illumination beam path, and a diaphragm, arranged in a pupil plane of the mask inspection microscope, for generating a resultant intensity distribution of the projection light in a pupil plane of the illumination beam path, wherein the diaphragm is embodied in such a way that the resultant intensity distribution of the projection light has at least one further intensity value between a minimum and a maximum intensity value, wherein the diaphragm has at least one region which is composed of light-transmissive and light-opaque pixels, such that the at least one further intensity value is formed by said at least one region, and wherein the distance between the pixels is embodied in such a way that only the zeroth diffraction order of the projection light diffracted at the diaphragm contributes to the at least one further intensity value.