Patent ID: 7372936

Claim:
A radiation computed tomography apparatus comprising: a radiation source; a radiation detector having a plurality of radiation detector elements arranged in a two-dimensional manner which is placed opposite to said radiation source so as to detect radiation exposed from said radiation source and passing through a subject positioned between said radiation source and said radiation detector; and a reconstructing device for reconstructing a tomographic image of said subject based on projection data for said subject from each of said plurality of radiation detector elements, said projection data obtained from values detected by said plurality of radiation detector elements, wherein said reconstructing device includes a correcting device configured to correct said projection data for each of said radiation detector elements by using a corrective value to reduce projection information by an effect of a plurality of scatter rays which should not be detected, wherein the corrective value is correlated with a path length of said radiation through said subject and with a width of an opening of a collimator configured to restrict the radiation.