Patent ID: 6316776
Filing Date: 2001-11-13
Classification: A61N

Abstract:
A method of irradiation with a charged particle beam, which is supplied from an accelerator to an irradiation apparatus comprising an electromagnet, and extracted from the irradiation apparatus for scanning with the charged particle beam, comprising the steps of:stopping the extraction of the charged particle beam from the irradiation apparatus by stopping the supply of the charged particle beam from the accelerator to the irradiation apparatus;changing an irradiation region of the charged particle beam by controlling the electromagnet under a condition when the extraction is stopped; andresuming the extraction of the charged particle beam from the irradiation apparatus after changing the irradiation region by resuming the supply of the charged particle beam from the accelerator;wherein if the charged particle beam, which is circulating in the accelerator during the stopping of the extraction of the charged particle beam from the irradiation apparatus, is sufficient for irradiation at a new irradiation region after the changing of the irradiation region, a residual charged particle beam in the accelerator is supplied to the irradiation apparatus from the accelerator without supplying charged particles from a charged particle generator; andwherein if the residual charged particle beam in the accelerator is insufficient for irradiation at the new irradiation region after the changing of the irradiation region, supply of the residual charged particle beam in the accelerator to the irradiation apparatus from the accelerator is resumed after supplying of charged particles from the charged particle generator to the accelerator.