System, apparatus and method for deflecting a particle beam

• US 8,378,312 B1
• Filed: 08/19/2011
• Issued: 02/19/2013
• Est. Priority Date: 08/19/2011
• Status: Active Grant

• Current Assignee: Pyramid Technical Consultants, Inc.
• Original Assignee: Pyramid Technical Consultants, Inc.
• Inventors: Gordon, John, Boisseau, Raymond Paul, Dart, Andrew
• Primary Examiner(s): Souw, Bernard E
• Application Number:
  US13/214,118
• Publication Number:
  US 20130043403A1
• Time in Patent Office: 550 Days
• Field of Search: 250/298, 250/306, 250/307, 250309-311, 250/396.ML, 250/396.R, 250/492.1, 250/492.2, 250/492.21, 250/492.22, 250/492.23, 250/492.3, 313/409, 313/413, 313/414, 313/416, 313/419, 313/421, 313/425, 313/427, 313/431, 313/435, 313/440, 313/44, 335/209, 335/210, 335/212, 335/213, 335/214, 335/230, 335/243, 335/246, 335/268, 335/289, 335/306, 315/5, 315/24, 315/5.26, 315/5.29, 315/5.35, 315/364, 31536825-36828, 315/397, 315/399, 315/403, 315/5.24, 315/403.4
• US Class Current: 250/396.R
• CPC Class Codes: A61N 2005/1087 Ions; Protons
• CPC Class Codes: A61N 5/1043 Scanning the radiation beam, e.g. spot scanning or raster scanning
• CPC Class Codes: G21K 1/093 by magnetic means
• CPC Class Codes: H05H 2007/046 for beam deflection

Abstract

A variety of systems, apparatus and methods for deflecting a particle beam are described. An apparatus comprises at least six electromagnetic portions disposed on a plane. Each of the at least six electromagnetic portions is aligned with a radius emanating from an axis normal to the plane and is distanced from the axis to form a volume about the axis. At least six coils are configured for affecting a dipole magnetic field in the volume in response to electrical currents applied to physically opposing coils where a particle beam entering the volume is deflected. Each of the at least six coils is disposed about a one of the at least six electromagnetic portions. A yoke structure is configured for returning a generated magnetic flux.

Claims

1. An apparatus comprising:

at least six electromagnetic portions disposed on a plane, each of said at least six electromagnetic portions being aligned with a radius emanating from an axis normal to said plane and being distanced from said axis to form a volume about said axis;

at least six coils being configured for generating a dipole magnetic field in said volume in response to electrical current patterns applied to physically opposing coils, said dipole magnetic field comprising vectors being generally equal in magnitude with a same direction of orientation on said plane traversing said axis, said orientation being rotatable about said axis in response to a change in said current patterns to deflect a particle beam entering said volume in a direction away from said axis, each of said at least six coils being disposed about a one of said at least six electromagnetic portions; and

a yoke structure being configured for returning a generated magnetic flux.

2. The apparatus as recited in claim 1, in which said at least six coils are further configured as at least three pairs of physically opposing coils, each of said at least three pairs being configured to be excited by a separate electrical current pattern.

3. The apparatus as recited in claim 2, in which said separate electrical current patterns comprise a sinusoidal component.

4. The apparatus as recited in claim 1, in which tips of said at least six electromagnetic portions that face said axis are shaped to affect the dipole magnetic field.

5. The apparatus as recited in claim 1, in which tips of said at least six electromagnetic portions that face said axis are shaped to vary the distance from said axis along a length of said tips to mitigate contact of said tips by said deflected particle beam.

6. The apparatus as recited in claim 1, in which said at least six electromagnetic portions are distanced from said axis to form a non-circular surface of said volume to correspond to a non-circular deflection pattern.

7. The apparatus as recited in claim 2, in which said separate electrical current patterns comprise a non-sinusoidal component to produce changes in a shape of the particle beam.

8. The apparatus as recited in claim 1, in which tips of said at least six electromagnetic portions that face said axis comprise devices for measuring said dipole magnetic field.

9. The apparatus as recited in claim 1, in which an amount of electromagnetic portions and an amount of coils is eight.

10. A system comprising:

at least six electromagnetic portions disposed on a plane, each of said at least six electromagnetic portions being aligned with a radius emanating from an axis normal to said plane and being distanced from said axis to form a volume about said axis;

at least six coils being configured for generating a dipole magnetic field in said volume in response to electrical current patterns applied to physically opposing coils, said dipole magnetic field comprising vectors being generally equal in magnitude with a same direction of orientation on said plane traversing said axis, said orientation being rotatable about said axis in response to a change in said current patterns to deflect a particle beam entering said volume in a direction away from said axis, each of said at least six coils being disposed about a one of said at least six electromagnetic portions;

a yoke structure being configured for returning a generated magnetic flux;

a plurality of power amplifiers for supplying said electrical current patterns;

a control system for monitoring and controlling operations of said power amplifiers; and

a power supply for powering at least said power amplifiers and said control system.

11. The system as recited in claim 10, in which said at least six coils are further configured as at least three pairs of physically opposing coils, each of said at least three pairs being configured to be excited by a separate one of said plurality of power amplifiers.

12. The system as recited in claim 11, in which said separate electrical current patterns comprise a sinusoidal component.

13. The system as recited in claim 10, in which tips of said at least six electromagnetic portions that face said axis are shaped to affect the dipole magnetic field.

14. The system as recited in claim 10, in which tips of said at least six electromagnetic portions that face said axis are shaped to vary the distance from said axis along a length of said tips to mitigate contact of said tips by said deflected particle beam.

15. The system as recited in claim 10, in which said at least six electromagnetic portions are distanced from said axis to form a non-circular surface of said volume to correspond to a non-circular deflection pattern.

16. The system as recited in claim 11, in which said separate electrical current patterns further comprise a non-sinusoidal component to produce changes in a shape of the particle beam.

17. The system as recited in claim 10, in which tips of said at least six electromagnetic portions that face said axis comprise devices for feedback to said control system.

18. The system as recited in claim 10, in which said at least six coils are further configured for generating said dipole magnetic field for use in particle therapy.

19. A method comprising steps of:

arranging at least six electromagnetic portions of a multi-pole electromagnet to be disposed on a plane where each of said at least six electromagnetic portions are aligned with a radius emanating from an axis normal to said plane and are distanced from said axis to form a volume about said axis;

configuring at least six coils for generating a dipole magnetic field in said volume in response to electrical current patterns comprising sinusoidal components being applied to physically opposing coils, said dipole magnetic field comprising vectors being generally equal in magnitude with a same direction of orientation on said plane traversing said axis, said orientation being rotatable about said axis in response to a change in said current patterns; and

exciting said at least six coils with said current patterns for rotating said dipole magnetic field to deflect a particle beam entering said volume to a desired position away from said axis.

20. The method as recited in claim 19, further comprising the step of applying a component to said electrical current patterns to shape the particle beam.