| 摘要 |
A particle beam irradiation chamber (1) is provided with a passage (3) having a first opening (7) on an inner wall side, and a second opening (8) on an outer wall side, an isocenter (6) being disposed inside the chamber, and is configured such that: a first line segment (9) connecting the center of the first opening (7) and the center of the second opening (8) passes through the interior of the passage (3); the angle formed between a second line segment (10) connecting the center of the first opening (7) and the isocenter (6), and the first line segment (9), is no greater than 180°; and the width of the passage (3) is smaller than the opening width of the first opening (7). |
