PROBLEM TO BE SOLVED: To provide a technique of reducing the influence of scattering of an X-ray in projection image data acquired in multi-energy scan.SOLUTION: An X-ray generator 11 generating an X-ray cone beam BX1 and a secondary X-ray detector 21 detecting the X-ray cone beam BX1 are supported in the facing state by a support arm 30 and rotated in the state of holding a subject M1 therebetween. An energy conversion part 23 in which filters 231, 233 having mutually-different conversion characteristics of the energy distribution of the X-ray beam are arrayed is arranged between the secondary X-ray detector 21 and the subject M1. An energy conversion part movement mechanism 25 moves the energy conversion part 23 in a direction along a detection surface 21S of the secondary X-ray detector 21 so that the energy conversion part traverses the X-ray cone beam BX1 during rotation of the support arm 30 in X-ray imaging.SELECTED DRAWING: Figure 4
