An X-ray optical transmission grating of a focus-detector arrangement of
an X-ray apparatus is disclosed, for generating projective or tomographic
phase contrast recordings of a subject. In at least one embodiment, the
grating includes a multiplicity of grating bars and grating gaps arranged
periodically on at least one surface of at least one wafer, wherein the
X-ray optical transmission grating includes at least two sub-gratings
arranged in direct succession in the beam direction.