Focus/detector system of an X-ray apparatus for generating phase contrast recordings

A method for generating tomographic recordings of a subject, the method comprising:

• scanning the subject at least one of circularly and spirally with at least one modularly constructed focus/detector system a phase shift of rays passing through the subject being determined by at least three intensity measurements with analysis gratings respectively arranged offset;
• interpolating the phase shift using neighboring values for rays which cannot be measured or cannot be measured accurately due to the modular construction of the detector;
• and
• reconstructing tomographic phase contrast recordings using the rays' phase shifts measured and determined by interpolation;
• wherein the focus/detector system includes,
• a beam source, including a focus and a focus-side source grating, arranged in the beam path to generate a field of ray-wise coherent X-rays;
• and
• a detector arrangement including a multiplicity of grating/detector modules arranged next to one another, which respectively comprise arranged successively in the beam direction:
• at least one phase grating to generate a first interference pattern,
• an analysis grating to generate a further interference pattern, and
• detector elements arranged flat, the individual grating lines of all gratings being aligned mutually parallel.

An X-ray system for generating projective phase contrast recordings, comprising:

• at least one focus/detector system for generating at least one of projective and tomographic phase contrast recordings, the system including,
• a beam source including a focus and a focus-side source grating, arranged in the beam path to generate a field of ray-wise coherent X-rays, and
• a detector arrangement including a multiplicity of grating/detector modules arranged next to one another, which respectively comprise arranged successively in the beam direction:
• at least one phase grating to generate a first interference pattern,
• an analysis grating to generate a further interference pattern, and
• detector elements arranged flat, the individual grating lines of all gratings being aligned mutually parallel;
• and
• a computation and control unit, containing program code that, when executed on the computation and control unit, the computation and control unit is configured to,
• scan the subject at least one of circularly and spirally with the at least one modularly constructed focus/detector system, the phase shift of the rays when passing through the subject being determined by at least three intensity measurements with analysis gratings respectively arranged offset,
• interpolate, the phase shift using neighboring values for rays which cannot be measured or cannot be measured accurately owing to the modular construction of the detector, and
• reconstruct tomographic phase contrast recordings using the rays' phase shifts measured and determined by interpolation.