To prepare a tomography synthesized photographic image without any other reference object by preparing the tomography synthesized photographic image from a signal derived from a beam detector by irradiating a reference object formed from an examination object and a signal derived by irradiating the examination object in the different direction.
An examination object 2 is arranged on the beam path of beam flux radiated from a beam transmitter 1 and an area 3 of the examination object 2 formed as a ball, for example, is defined as a reference object 4. The ball 3 is reversibly fixed on the examination object 2 by an adhesive agent, for example, the shadow of the examination object 2 and the ball 3 formed by beams is caught by a beam detector 5 and the output signal of the beam detector 5 is supplied to an image forming device 6 for forming the tomography synthesized image of the examination object 2. The reference object 4 is let exist in contact with the examination object 2, inside the examination object 2 or near the examination object 2 at least.