PROBLEM TO BE SOLVED: To provide means for analyzing an error between a radiation irradiation field and a light irradiation field in a radiotherapy apparatus.SOLUTION: An error analyzer 10 includes: (1) a light receiving box 1 which is a housing formed of a front plate part 2 and a rear plate part 3 and includes a storage chamber for radiation photosensitive paper 4 between the front plate part and the rear plate part and (2) support means 5 for supporting the light receiving box so that it can be rotated and locked at an arbitrary angle. The front plate part includes an irradiation wall part 23 made of a radiation permeable material. A light irradiation field confirmation pattern 25 is provided on the surface of the irradiation wall part, and position confirmation marker means 27 for the radiation photosensitive paper in the storage chamber is provided in the irradiation wall part.COPYRIGHT: (C)2015,JPO&INPIT【課題】放射線治療装置における放射線照射野と光照射野との誤差を分析する手段を提供する。【解決手段】誤差分析器10は、(1)表板部2と裏板部3とから形成される筐体であって、前記表板部と前記裏板部との間に放射線感光紙4の収納室を含む受光箱1、及び(2)前記受光箱を回転可能及び任意の角度で係止可能に支持する支持手段5を含み、前記表板部は、放射線透過性材料からなる照射壁部23を有し、前記照射壁部の表面に光照射野確認用パターン25を備え、照射壁部に収納室内の放射線感光紙の位置確認用マーカー手段27を備えることを特徴とする。【選択図】図1
