PROBLEM TO BE SOLVED: To provide a radiation detection assembly capable of switching spacial resolution in a simple constitution for a radiation tomography.SOLUTION: A radiation detection assembly 28 comprises a plurality of radiation detection elements 56i which are disposed opposite to a radiation source for emitting a radiation 81 to an object to be imaged a plurality of collimator plates 55 which divide a plurality of radiation detection elements 56i along a channel direction (CH direction) and are erected with their plate surfaces along the direction of the radiation from the radiation source and opening width changing means 57a, 57b, and 60 which change each opening width formed by a plurality of the collimator plates 55 by moving a plurality of radiation absorption members 57 extended along an end side direction of end parts of a plurality of collimator plates 55 close to the radiation source between a first arrangement where the radiation absorption members 57 are substantially overlapped with the end parts of the collimator plates and a second arrangement where the absorption members 57 are deviated in the channel direction from the end parts in the range where no gap is formed between the absorption members 57 and the end parts of the collimator plates 55.COPYRIGHT: (C)2013,JPO&INPIT【課題】放射線断層撮影において、シンプルな構成で空間分解能の切換えを可能にする。【解決手段】撮影対象に放射線81を照射する放射線源に対向して配置される複数の放射線検出素子56iと、複数の放射線現出素子56iをチャネル方向(CH方向)に区分する複数のコリメータ板55であって、それぞれの板面が放射線源からの放射方向に沿うように立設された複数のコリメータ板55とを備えた放射線検出装置28において、複数のコリメータ板55における放射線源寄りの各端部の端辺方向に沿って延びる複数の放射線吸収部材57を、その端部と実質的に重なる第1の配置と、その端部からチャネル方向に、その端部との間に間隙が形成されない範囲においてずれた第2の配置とに移動させることにより、複数のコリメータ板56iによって形成される各開口の幅を変更する開口幅変更手段57a,57b,60とを備える構成とする。【選択図】図5
