Patent ID: 8841638

Claim:
A particle beam therapy system comprising an irradiation unit having a scanning electromagnet for irradiating an irradiation object by scanning a particle beam which travels in a vacuum duct and a beam outlet window from which a particle beam comes out from the vacuum duct to the atmosphere, wherein the irradiation unit has the configuration such that a vacuum duct is provided which can be divided by a flange surface at an irradiation object side of the scanning electromagnet, in a case where a vacuum duct for a scanning irradiation method is provided at an irradiation object side of the flange surface, a ridge filter for a scanning irradiation method is provided at the irradiation object side of the vacuum duct for a scanning irradiation method, in a case where the vacuum duct for a scanning irradiation method is moved so as not to overlap with a beam line of the particle beam, the ridge filter for a scanning irradiation method is removed and a ridge filter for a broad beam irradiation method can be provided in space which is on a beam line of a particle beam and where the vacuum duct for a scanning irradiation method was provided before it was moved.