A deflection mirror (1, 501, etc.) for a microlithography projection exposure apparatus for illuminating an object field in an object plane of the projection exposure apparatus (1067) using the deflection mirror with grazing incidence. This deflection mirror has a substrate (3, 503, etc.) and at least one layer system (5, 505, etc.), and during operation light impinges on said mirror at a multiplicity of angles of incidence, wherein the layer system is designed such that, for light having a wavelength of less than 30 nm, for an angle of incidence of between 55° and 70°, the variation of the reflectivity is less than 20%, in particular less than 12%.