Tomosynthesis system with a rotating anode X-ray tube enabling a circular scan trajectory, wherein the X-ray tube 1 may be equipped with a large number of cathodes (21, 22) distributed around an anode. This allows to generate X-rays (41, 42) at focal spot positions (11, 12), for example evenly distributed on a for example circular line (14) on the surface (15) of an anode (10). The object (61) may be located on the (10) axis of rotation (6) of the anode at some distance to the source. For an examination, the object (61) may be exposed to X-ray beams (41, 42) generated successively on all focal spot positions (11, 12), wherein no movement of the X-ray tube 1 is necessary. The transmitted X-ray intensities may be measured by a flat panel detector (50) to achieve a reconstructed three-dimensional image data.