Patent Number: 
Section: claims

1. An X-ray optical transmission grating of a focus-detector arrangement of an X-ray apparatus for generating at least one of projective and tomographic phase contrast recordings of a subject, comprising:at least one wafer including a multiplicity of grating bars and grating gaps, the grating bars and grating gaps being arranged periodically on at least one surface of the at least one wafer, wherein the X-ray optical transmission grating includes at least two sub-gratings arranged in direct succession in a beam direction, wherein a beam profile of a transmitted X-radiation is designed to be at least one of fan-shaped and conical, and the sub-gratings arranged successively in the beam direction comprise different grating periods, and wherein a grating period increases from at least one sub-grating to at least one subsequent sub-grating and the sub-gratings are arranged to be mutually aligned, so that the rays of the beam pass through only one of either of the grating gaps or the grating bars. 2. An X-ray optical transmission grating of a focus-detector arrangement of an X-ray apparatus for generating at least one of protective and tomographic phase contrast recordings of a subject, comprising:at least one wafer including a multiplicity of grating bars and grating gaps, the grating bars and grating gaps being arranged periodically on at least one surface of the at least one wafer, wherein the X-ray optical transmission grating includes at least two sub-gratings arranged in direct succession in a beam direction, wherein a filler material with a relatively higher linear attenuation coefficient than the wafer material in the relevant energy range is arranged in the grating gaps of at least one sub-grating, wherein the transmission grating is a phase grating and, for the sum of the sub-gratings, the height of the filler material in the gaps is dimensioned so that the X-radiation with the energy used for measuring the phase shift generates a phase shift of λ/2 in the X-radiation and after the entire grating, at least in relation to the energy used for measuring the phase shift, the attenuation of the X-radiation is the same after passing through the bars and when passing through the filler material. 3. An X-ray optical transmission grating of a focus-detector arrangement of an X-ray apparatus for generating at least one of projective and tomographic phase contrast recordings of a subject, comprising:at least one wafer including a multiplicity of grating bars and grating gaps, the grating bars and grating gaps being arranged periodically on at least one surface of the 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, wherein a filler material with a relatively higher linear attenuation coefficient than the wafer material in the relevant energy range is arranged in the grating gaps of at least one sub-grating, wherein the transmission grating is a phase grating and, for each of the sub-gratings individually, the height of the filler material in the gaps is dimensioned so that the X- radiation with the energy used for measuring the phase shift generates a phase shift in the X-radiation of λ/2 and after each sub-grating, at least in relation to the energy used for measuring the phase shift, the attenuation of the X-radiation is the same when passing through the bars and after passing through the filler material. 4. The transmission grating as claimed in claim 1, wherein at least two sub-gratings arranged on a separate wafers comprise markings by which mutual alignment is made possible. 5. A focus-detector arrangement of an X-ray apparatus for generating at least one of projective and tomographic phase contrast recordings of a subject, wherein at least one of X-ray optical gratings used is designed as the transmission grating of claim 1. 6. The transmission grating as claimed in claim 2, wherein at least two sub-gratings arranged on a separate wafers comprise markings by which mutual alignment is made possible. 7. The transmission grating as claimed in claim 3, wherein at least two sub-gratings arranged on a separate wafers comprise markings by which mutual alignment is made possible. 8. A focus-detector arrangement of an X-ray apparatus for generating at least one of projective and tomographic phase contrast recordings of a subject, wherein at least one of X-ray optical gratings used is designed as the transmission grating of claim 2. 9. A focus-detector arrangement of an X-ray apparatus for generating at least one of projective and tomographic phase contrast recordings of a subject, wherein at least one of X-ray optical gratings used is designed as the transmission grating of claim 3. 10. An X-ray system for generating projective phase contrast recordings, comprising the X-ray optical transmission grating of the focus-detector arrangement of claim 1. 11. An X-ray system for generating projective phase contrast recordings, comprising the X-ray optical transmission grating of the focus-detector arrangement of claim 2. 12. An X-ray system for generating projective phase contrast recordings, comprising the X-ray optical transmission grating of the focus-detector arrangement of claim 3. 13. An X-ray C-arc system for generating projective or tomographic phase contrast recordings, comprising the X-ray optical transmission grating of the focus-detector arrangement of claim 1. 14. An X-ray C-arc system for generating projective or tomographic phase contrast recordings, comprising the X-ray optical transmission grating of the focus-detector arrangement of claim 2. 15. An X-ray C-arc system for generating projective or tomographic phase contrast recordings, comprising the X-ray optical transmission grating of the focus-detector arrangement of claim 3. 16. An X-ray computer tomography system for generating tomographic phase contrast recordings, comprising the X-ray optical transmission grating of the focus-detector arrangement of claim 1. 17. An X-ray computer tomography system for generating tomographic phase contrast recordings, comprising the X-ray optical transmission grating of the focus-detector arrangement of claim 2. 18. An X-ray computer tomography system for generating tomographic phase contrast recordings, comprising the X-ray optical transmission grating of the focus-detector arrangement of claim 3.