Patent ID: 6947516

Claim:
An X-ray CT apparatus, comprising: an X-ray source configured to generate X-rays towards a subject; a rotation mechanism configured to rotate the X-ray source around a rotational axis; an X-ray detector having a plurality of detection elements arranged in a first direction roughly parallel to the rotational axis and in a second direction which is different from the first direction and configured to detect X-rays emitted from the X-ray source; a blocking member located between the X-ray source and the X-ray detector and configured to block X-rays; a reconstruction unit configured to reconstruct an image of the subject in accordance with the data detected by the X-ray detector; and the blocking member comprising an aperture including a first section and a second section, the second section located in the first direction in relation to the first section and staggered in relation to the first section in the second direction; wherein a plurality of apertures is located at prescribed intervals in the second direction; wherein the rotational axis is arranged such that a line projecting the rotational axis from the X-ray source on to the X-ray detector is staggered in the second direction in relation to an alignment-centered axis of the X-ray detector; wherein the line projecting the rotational axis is staggered by roughly ¼ the width of the detection element in the second direction, the first section of the aperture is staggered by roughly ¼ the width of the detection element in the second direction in relation to the second section of the aperture, the center of the second section of the aperture is staggered by roughly ⅜ the width of the detection element in the second direction in relation to the alignment-centered axis, and the widths of the first section and the second section are roughly ½ detection element, respectively, in the second direction.