an X-ray tube that generates X-rays;

an X-ray detector that detects an X-ray passing through an object;

a supporting member that rotatably supports the X-ray tube and the X-ray detector around a rotational axis;

a reconstructing unit configured to reconstruct an image on the basis of an output of the X-ray detector;

an information creating unit configured to create information concerning an arrangement of an asymmetrical field of view of the object when a field of view of a scanogram by the X-ray tube and the X-ray detector is asymmetric with respect to an imaging center line in a direction perpendicular to the rotational axis; and

a display unit that displays information concerning the arrangement,

wherein the information creating unit is configured to create information for displaying an asymmetric sectorial picture that corresponds to the asymmetrical field of view so as to correspond to a scanogram angle, and

wherein the information creating unit is configured to create information for displaying a plurality of icons that resemble the X-ray tube, and correspond to scanogram angles together with the asymmetrical sectorial picture.