X-ray image acquisition system for differential phase contrast imaging of an examination object by way of phase stepping, and angiographic examination method
In an embodiment of an X-ray image acquisition system, an X-ray image detector includes a detector layer having a matrix composed of x total pixels structured in such a way that in a direction standing perpendicularly with respect to the grating lines of the diffraction or phase grating, the total pixels are subdivided into y subpixels which can be driven and/or read out in groups in a readout process such that, in a first phase step, n subpixels are effectively combined into groups, with m subpixels of a total pixel between the groups not being captured, and such that, in subsequent K−1 phase steps, n subpixels are in each case combined again into groups until all necessary combinations of subpixels have been captured, with the combined subpixels being shifted in the analysis direction by an increment of p subpixels in each case.