The invention relates to an X-ray detector arrangement (10) for X-ray phase contrast tomo-synthesis imaging, a line detector (1) for X-ray phase contrast tomo-synthesis imaging, an imaging system (24) for X-ray phase contrast tomo-synthesis imaging, a method for X-ray phase contrast tomo-synthesis imaging, and a computer program element for controlling such arrangement and a computer readable medium having stored such computer program element. The X-ray detector arrangement (10) comprises several line detectors (1). Each line detector (1) is configured to detect a Moiré pattern in at least a portion of an X-ray beam (2) impacting such line detector (1). Each line detector (1) comprises several detector lines (11), wherein a width W of each line detector (1) equals one period or an integer multiple of the period of the Moiré pattern.
