| 摘要 |
A charged particle beam apparatus having a reduced loss of the charged particle beam, and a method for operation the same are provided. <??>In accordance with information such as a shape of affected part, and others, irradiation positions in a horizontal direction and a necessary irradiation dose are previously designated. An interval between the irradiation positions in the horizontal direction is desirably designated as smaller than a half of the charged particle beam size enlarged by a scatterer. A control unit controls a power source of electromagnets in order to change an irradiation position during stopping extraction of the charged particle beam. An affected part is irradiated with the charged particle beam per respective irradiation position. An irradiation target can be irradiated uniformly with the charged particle beam by overlapping the charged particle beam, because the irradiation dose of the charged particle beam enlarged by the scatterer has a Gaussian distribution in a radial direction centered at the irradiation position. In comparison with a case when the charged particle beam enlarged by a scatterer in order to cover all the region of the affected part, ununiformly irradiated region formed around the affected part can be minimized, and the loss of the charged particle beam can be reduced. In comparison with another case when the scatterer is not used, the number of changing the irradiation position is small because the size of the beam of the present invention is larger than the other case, and the controlling method can be simplified. <IMAGE> |
