US Patent 7769129 X-ray computed tomography apparatus

An X-ray computed tomography apparatus includes an X-ray tube (101) which generates X-rays, a multi-channel X-ray detector (103) which detects X-rays transmitted through an object to be examined, a rotating frame (102) which is equipped with the X-ray tube and the X-ray detector, a reconstruction unit (114) which reconstructs an image on the basis of an output from the X-ray detector, and a control unit (121) which alternately shifts the X-ray focal spot of the X-ray tube along the rotating direction on the anode by a distance +σ and a distance −σ for each view. The distance σ is set to