An X-ray generator 11 generating an X-ray cone beam BX11 and a two-dimensional X-ray detector 21 detecting the X-ray cone beam BX1 are supported by a support arm 30 while facing each other, and the X-ray generator 11 and the two-dimensional X-ray detector 21 are turned with an object M1 interposed therebetween. An energy conversion unit 23 is disposed between the two-dimensional X-ray detector 21 and the object M1. Filters 231 and 233 having X-ray beam energy distribution conversion characteristics different from each other are arrayed in the energy conversion unit 23. In X-ray photography, an energy conversion unit moving mechanism 25 is moved in a direction along a detection surface 21S of the two-dimensional X-ray detector 21 such that the energy conversion unit 23 traverses the X-ray cone beam BX11 in turning the support arm 30.
