PROBLEM TO BE SOLVED: To provide an X-ray CT system which divides scan, sets an irradiation field, and carries out photography using the irradiation field so as to irradiate a designated region in a region of interest with X rays in a desired X-ray dose.SOLUTION: The X-ray CT system includes an X-ray tube 001, a collimator 002, and a detector 004 having a plurality of rows of detecting elements in the body axis direction. The X-ray CT system further includes an imaging region data acquisition part 014 that divides a whole imaging region of a subject P in the body axis direction into a first imaging region imaged with a first X-ray dose and a second imaging region imaged with a second X-ray dose and acquires designated imaging region data, an irradiation field regulating part 017 that acquires a first irradiation field of the first imaging region and a second irradiation field of the second imaging region and controls the collimator 002 during scan imaging of the each region so that the acquired irradiation field is achieved, and an X-ray control section 016 that controls the X-ray tube 001 to irradiate the first imaging region with the first X-ray dose and the second imaging region with the second X-ray dose.COPYRIGHT: (C)2011,JPO&INPIT【課題】関心領域の中の指定した領域に対して所望のX線照射量でX線の照射が行われるようにスキャンを分割し、その照射野を求め、その照射野を用いて撮像を行うX線CT装置を提供する。【解決手段】X線管001と、コリメータ002と、検出素子列を前記体軸方向に複数有する検出器004と、を備えたX線CT装置であって、被検体Pの全体の撮影領域を体軸方向に第1X線量で撮影する第1撮影領域、及び第2X線量で撮影する第2撮影領域に区分して指定された撮影領域データを取得する撮影領域データ取得部014と、第1撮影領域の第1照射野及び第2撮影領域の第2照射野を求め、各領域のスキャン撮影時に求めた照射野になるようにコリメータ002を制御する照射野制御部017と、前記第1撮影領域に対して前記第1X線量を照射し、前記第2撮影領域に対して前記第2X線量を照射するように、X線管001を制御するX線制御部016とを備える。【選択図】図1
