Magnetic field control method and apparatus used in conjunction with a charged particle cancer therapy system
View Patent ↗The invention comprises a charged particle beam acceleration, extraction, and/or targeting method and apparatus used in conjunction with charged particle beam radiation therapy of cancerous tumors. Novel design features of a synchrotron are described. Particularly, turning magnets, edge focusing magnets, concentrating magnetic field magnets, winding and control coils, flat surface incident magnetic field surfaces, and extraction elements are described that minimize the overall size of the synchrotron, provide a tightly controlled proton beam, directly reduce the size of required magnetic fields, directly reduces required operating power, and allow continual acceleration of protons in a synchrotron even during a process of extracting protons from the synchrotron.
1. An apparatus for acceleration of charged particles in a charged particle beam path, comprising:
a pair of magnets;
a first foil magnetic penetration layer, said foil magnetic penetration layer less than about one-tenth of a millimeter thickness, said penetration layer comprising a first side and a second side, said second side of said foil comprising a surface roughness of less than about three microns; and
said charged particle beam path running through a gap between said pair of magnets,
wherein a first magnet of said pair of magnets comprises a gap surface, said gap surface coplanar with said first side of said foil, said second side of said foil proximate said gap.
2. The apparatus of claim 1 , further comprising a non-magnetic isolating layer, said isolating layer comprising a thickness of at least about 0.05 mm and less than about 0.5 mm, said isolating layer comprising a first side and a second side; said isolating layer separating said gap surface from said first side of said foil.
3. The apparatus of claim 1 , further comprising a synchrotron using said pair of magnets in acceleration of the charged particles, said synchrotron further comprising:
an extraction material;
at least a one kilovolt direct current field applied across a pair of extraction blades; and
a deflector,
wherein the charged particles pass through said extraction material resulting in a reduced energy charged particle beam,
wherein the reduced energy charged particle beam passes between said pair of extraction blades, and
wherein the direct current field redirects the reduced energy charged particle beam through said deflector,
wherein said deflector yields an extracted charged particle beam.
4. The apparatus of claim 1 , further comprising a synchrotron using said pair of magnets in acceleration of the charged particles, said synchrotron further comprising: multi-axis control, said multi-axis control comprising control of:
an energy; and
an intensity; and
a rotatable platform,
wherein said control of said energy and said control of said intensity occurs during extraction,
wherein said rotatable platform rotates through at least one hundred eighty degrees during an irradiation period,
wherein said multi-axis control operates during at least ten rotation positions of said rotatable platform.
5. The apparatus of claim 4 , wherein said multi-axis control further comprises independent control of all of:
a horizontal position of the charged particles;
a vertical position of the charged particles;
said energy; and
said intensity, wherein said multi-axis control comprises delivery of the charged particles during said at least ten rotation positions of said rotatable platform.