This invention relates to tomographic imaging, and particularly to producing complex motion or spiral tomography images in medical X-ray imaging. According to the invention, a curved path is arranged for the radiation source of the imaging apparatus in the vertical direction with respect to the object to be imaged, and a counter-movement with respect to the curved movement of the radiation source in the vertical is implemented by moving the radiation detector substantially linearly with respect to the radiation source on the opposite side of the object to be imaged. It is also preferable to keep the detector constantly parallel with a cross-sectional plan through the object to be imaged.