PROBLEM TO BE SOLVED: To enhance detection efficiency of a detector by suppressing a sensitivity change of each detection element by heat transfer of an X-ray focus and crosstalk between the detection elements, in an X-ray CT apparatus and the X-ray detector disposed with a scattered radiation prevention grid.SOLUTION: The X-ray CT apparatus includes: an X-ray source generating X-rays from an X-ray focus position an X-ray detection element array wherein the X-ray detection elements for detecting X-rays are two-dimensionally arranged in first and second directions with separators therebetween the scattered radiation prevention grid, wherein X-ray transmission members and X-ray shielding members disposed between the X-ray detection element array and the X-ray focus are alternately arranged in the first and second directions, and wherein the X-ray shielding members each have a slant angle oriented to the X-ray focus and at least one X-ray detector module with the X-ray detection element array as a unit. The separators are inclined against an X-ray focus direction within a range wherein the separators are stored in areas of the shadow of the X-rays generated by the X-ray shielding members of the scattered radiation prevention grid.COPYRIGHT: (C)2012,JPO&INPIT【課題】散乱線防止グリッドが配置されるX線検出器およびX線CT装置において、検出素子間のクロストーク及びX線焦点の熱移動による検出素子の感度変化を抑制し、検出器の検出効率を向上させることを目的とする。【解決手段】X線焦点位置からX線を発生するX線源と、X線を検出するためのX線検出素子がセパレータを隔てて第1及び第2の方向へ二次元配列されているX線検出素子アレイと、前記X線検出素子アレイと前記X線焦点の間に配置されX線透過部材とX線遮蔽部材が交互に前記第1及び第2の方向に配列され前記X線遮蔽部材が前記X線焦点へ指向する傾斜角を有する散乱線防止グリッドと、前記X線検出素子アレイを単位として、一つ以上のX線検出器モジュールと、を備えたX線CT装置であって、前記セパレータが、前記散乱線防止グリッドのX線遮蔽部材によって生じるX線の影の領域に収まる範囲内で、前記X線焦点方向に対して傾斜している。【選択図】図5A
