PROBLEM TO BE SOLVED: To provide a particle ray irradiation apparatus which prevents a radiation dose-deficient region from being generated to allow formation of a precise distribution of radiation dose.SOLUTION: The particle ray irradiation apparatus, which irradiates an irradiated object P1 with particle ray b1 sent from an accelerator 6, includes an irradiation dose monitor 3, a primary counter C1, and a secondary counter C2, wherein the irradiation dose monitor 3 determines the exposure dose of the particle ray b1 with which the irradiated object P1 is irradiated the primary counter C1 bases on the signals of the exposure doses transmitted from the irradiation dose monitor 3 to integrate the doses of particle ray b1 to which the object P1 is exposed when the apparatus is set to irradiate the object P1 with particle ray b1 and the secondary counter C2 bases on the signals of the exposure doses to integrate the leaked doses of particle ray b1 to which the object P1 is unintentionally exposed when the apparatus is set to exempt the object P1 from being irradiated with particle ray b1.COPYRIGHT: (C)2011,JPO&INPIT【課題】本発明の課題は、線量不足の領域が発生してしまうことを防ぎつつ、精細な線量分布形成を可能とする粒子線照射装置を提供することにある。【解決手段】本発明に関わる粒子線照射装置は、加速器6から送られる粒子線b1を照射対象P1に照射する粒子線照射装置1であって、照射対象P1に照射される粒子線b1の照射量を測定する線量モニタ3と、粒子線b1を照射対象P1に照射中の粒子線b1の線量を、線量モニタ3から送信される照射量の信号に基づいて、積算する第1のカウンタC1と、粒子線b1を照射対象P1に照射しないように設定される非照射時の意図せず照射対象P1に照射される粒子線b1の漏れ線量を、照射量の信号に基づいて、積算する第2のカウンタC2とを備える。【選択図】図1
