PROBLEM TO BE SOLVED: To accurately measure particle beam characteristics executed prior to a particle beam therapy in a same state as particle beam characteristics during the particle beam therapy.SOLUTION: The particle beam therapy apparatus irradiates a particle beam 3 via an irradiation port 14. The irradiation port 14 has a transmission part 33 through which the particle beam 3 transmits, and a cover 30. The cover 30 is divided into a first cover part 27 for covering the transmission part 33, and a second cover part 28 for covering an area other than the transmission part 33 in the irradiation port 14. The second cover part is configured to be attachable/detachable independently.SELECTED DRAWING: Figure 2COPYRIGHT: (C)2017,JPO&INPIT【課題】粒子線治療に先立って行なう粒子線特性の計測を、粒子線治療中の粒子線特性と同一の状態で正確に計測できること。【解決手段】照射ポート14を通じて粒子線3を照射する粒子線治療装置において、照射ポート14は、粒子線3が透過する透過部33を有すると共に、カバー30を備え、このカバー30は、透過部33を覆う第1カバー部27と、照射ポート14における透過部33を除く領域を覆う第2カバー部28とに分割され、この第2カバー部が独立して着脱可能に構成されたものである。【選択図】 図2
