A phase contrast X-ray imaging system of an object includes an X-ray source, an X-ray detector arrangement, and a grating arrangement with a phase-grating structure and an analyzer-grating structure. The X-ray detector arrangement includes at least eight line-detector units parallel to each other in a first direction, the line-detector units extending linearly in a direction perpendicular to the first direction. The phase-grating structure has a number of linear phase-gratings having a first part with first phase-gratings with slits in the first direction, and a second part with second phase-gratings with slits in a second direction different than the first direction. The analyzer-grating structure has a number of linear analyzer-gratings having a first part with first analyzer-gratings with slits in the first direction, and a second part with second analyzer-gratings with slits in the second direction.
