The device has a C-shaped bracket or frame (1). An X-ray emitter (2) and image generating system (3) are arranged at the ends of the frame (1). The frame (1) is adjustable in the circumferential direction and can be rotated about a horizontal axis (11). The frame is also height adjustable. The adjustment of the frame (1) is such that the central beam (8) of the X-ray emitter (2) runs through an isocentre (15). A light source (13) is arranged on the C-shaped frame (1). The light source emits a light beam (14) which runs through the isocentre (15). The light source is preferably arranged in the middle of the frame (1).
