Energy degrader and charged particle irradiation system including the same

• US 8,618,519 B2
• Filed: 04/25/2012
• Issued: 12/31/2013
• Est. Priority Date: 12/27/2010
• Status: Active Grant

• Current Assignee: Sumitomo Heavy Industries Limited
• Original Assignee: Sumitomo Heavy Industries Limited
• Inventors: Ueda, Takamasa
• Primary Examiner(s): Berman, Jack
• Assistant Examiner(s): Chang, Hanway
• Application Number:
  US13/455,754
• Publication Number:
  US 20120267544A1
• Time in Patent Office: 615 Days
• Field of Search: 250/492.1, 250/492.2, 250/492.3, 250/396.R, 250/396.ML
• US Class Current: 250/492.3
• CPC Class Codes: A61N 2005/1087 Ions; Protons
• CPC Class Codes: A61N 2005/1095 Elements inserted into the radiation path within the system, e.g. filters or wedges
• CPC Class Codes: A61N 5/1043 Scanning the radiation beam, e.g. spot scanning or raster scanning
• CPC Class Codes: G21K 1/10 Scattering devices; Absorbing devices; Ionising radiation filters
• CPC Class Codes: H05H 2007/004 for modifying beam energy, e.g. spread out Bragg peak devices
• CPC Class Codes: H05H 7/12 Arrangements for varying final energy of beam

Abstract

An energy degrader includes: an attenuation member that attenuates energy of entering charged particles to a different amount of energy according to an incident position of the charged particles; an energy adjustment drive unit that drives the attenuation member in a first axial direction in order to change the incident position of the charged particles; and a beam diameter adjustment drive unit that drives the attenuation member in a second axial direction different from the first axial direction in order to adjust the beam diameter of the charged particles.

Claims

1. An energy degrader comprising:

an attenuation member that attenuates energy of entering charged particles to a different amount of energy according to an incident position of the charged particles;

an energy adjustment drive unit that drives the attenuation member in a first axial direction in order to change the incident position of the charged particles; and

a beam diameter adjustment drive unit that drives the attenuation member in a second axial direction different from the first axial direction in order to adjust the beam diameter of the charged particles.

2. The energy degrader according to claim 1, further comprising:

a second attenuation member that is disposed on the upstream or downstream side of the attenuation member in a traveling direction of the charged particles and attenuates energy to a different amount of energy according to incident position of the charged particles; and

a second energy adjustment drive unit that drives the second attenuation member in the first axial direction in order to change the incident position of the charged particles.

3. The energy degrader according to claim 2,

wherein the attenuation member is disposed on the upstream side of the second attenuation member in the traveling direction of the charged particles.

4. A charged particle irradiation system that includes the energy degrader according to claims 1 and performs the irradiation of the charged particles, the charged particle irradiation system comprising:

an accelerator that accelerates the charged particles to be introduced into the energy degrader; and

an irradiation device that performs the irradiation of the charged particles of which energy has been attenuated by the energy degrader.

5. An energy degrader comprising:

an attenuation member that attenuates energy of entering charged particles to a different amount of energy according to an incident position of the charged particles;

energy adjustment drive means for driving the attenuation member in a first axial direction in order to change the incident position of the charged particles; and

beam diameter adjustment drive means for driving the attenuation member in a second axial direction different from the first axial direction in order to adjust the beam diameter of the charged particles.