PROBLEM TO BE SOLVED: To improve image quality of diagnostic images to be obtained while suppressing the total dose of a subject when irradiating the subject with X-rays and making a diagnosis.SOLUTION: Sections formed by partitioning a plane of a certain height on a top plate 2 where a subject P is mounted into a plurality of planes, is set and the subject P is irradiated with X-rays while monitoring integral dose of the X-rays with which the section is irradiated, so that the dose of the X-rays to be applied is increased to improve the image quality of diagnostic images to be obtained before the integral dose of the X-rays with which each section is irradiated reaches a threshold, whereas when the integral dose of the X-rays with which a certain section is irradiated reaches the threshold, the dose of the X-rays with which the certain section is irradiated is reduced to suppress the exposure to the subject P, and thus, the diagnostic images of high image quality are obtained while suppressing the total exposure of the subject P.COPYRIGHT: (C)2014,JPO&INPIT【課題】被検体にX線を照射して診断する場合に、被検体の総被ばく量を抑えつつ得られる診断画像の画質を高くする。【解決手段】被検体Pが載置される天板2上の或る高さの平面を複数に仕切った区画を設定し、その区画に対して照射されるX線の積算線量を監視しながら被検体Pに対するX線照射を行うことにより、各区画に対するX線の積算線量が閾値に達する前は照射されるX線の線量を多くして得られ診断画像の画質を高くし、或る区画に対するX線の積算線量が閾値に達した場合には、その区画に対して照射されるX線の線量を低減させることにより被検体Pに対する被ばく量を抑え、これにより、被検体Pの総被ばく量を抑えつつ、画質の高い診断画像を得る。【選択図】図1
