Patent Number: 
Section: claims

1. A radiotherapy apparatus incorporating multi-source focusing therapy and conformal and intensity-modulated therapy, comprising a base, a movable couch, a gantry, at least one therapeutic head, and a counterweight, the movable couch and the gantry are disposed on the base, the therapeutic head and the counterweight are oppositely positioned on the gantry, wherein, the therapeutic head comprises:a shielding part configured for shielding radiation beams from at least one radioactive source;a source carrier received in the shielding part, provided with a focusing radioactive source for focused therapy and a conformal radioactive source for conformal and intensity-modulated radiotherapy;a switch part positioned on an emitting side of the focusing radioactive source and the conformal radioactive source, and wherein the switch part comprises at least one through hole to be aligned with the focusing radioactive source or the conformal radioactive source for passing through the radiation beams while the switch part is rotated to at least one predetermined position;a shielding door positioned on one side of the switch part away from the source carrier, configured for controllably shielding the radiation beams of the radioactive sources; anda collimator assembly comprising a collimator carrier, a plurality of focusing collimators and a multi-leaf collimator, wherein the focusing collimators and multi-leaf collimator are disposed on the collimator carrier. 2. The radiotherapy apparatus of claim 1, wherein at least two rows of focusing radioactive sources are arranged on opposite sides of the source carrier, and a conformal radioactive source is disposed in middle of the source carrier. 3. The radiotherapy apparatus of claim 2, wherein each said row comprises nine focusing radioactive source for focused therapy and is equidistantly distributed in an arc sector with a central angle arranged between 26° to 60°, along an axial cross section of the gantry. 4. The radiotherapy apparatus of claim 3, wherein the at least two rows of focusing radioactive sources are distributed on two sides of the conformal radioactive source with an included angle arranged between 26° to 60°, along an radial cross section of the gantry. 5. The radiotherapy apparatus of claim 4, wherein the at least one through hole comprises two rows of first through holes provided on two lateral lines of the switch part and corresponding to the focusing radioactive source for focused therapy, and a second through hole arranged in middle of the switch part corresponding to the conformal radioactive source for conformal therapy, and the second through hole is offset from a symmetry line of the two rows of first through holes. 6. The radiotherapy apparatus of claim 3, wherein the at least one through hole comprises two rows of first through holes provided on two lateral lines of the switch part and corresponding to the focusing radioactive source for focused therapy, and a second through hole arranged in middle of the switch part corresponding to the conformal radioactive source for conformal therapy, and the second through hole is offset from a symmetry line of the two rows of first through holes. 7. The radiotherapy apparatus of claim 1, wherein all of the focusing collimators are mounted on the collimator carrier and capable of moving together with the collimator carrier, and comprises three groups of collimating holes corresponding to the source carrier for directing the focusing radiation from the focusing radioactive sources, each said group of collimating holes comprises two rows of collimating holes with same aperture diameter, and distance between the two rows of collimating holes in each said group is equal, and the apertures size of the collimating holes in different group are different. 8. The radiotherapy apparatus of claim 7, wherein a square hole is disposed in middle of the said groups of collimating holes, and the multi-leaf collimator is received in the square hole. 9. The radiotherapy apparatus of claim 1, wherein the at least one through hole comprises two rows of first through holes provided on two lateral lines of the switch part and corresponding to the focusing radioactive source for focused therapy, and a second through hole arranged in middle of the switch part corresponding to the conformal radioactive source for conformal therapy, and the second through hole is offset from a symmetry line of the two rows of first through holes. 10. The radiotherapy apparatus of claim 1, wherein the shielding door comprises two layers which are respectively movable in perpendicular directions to mutually be opened or closed. 11. The radiotherapy apparatus of claim 1, wherein the at least one through hole comprises two rows of first through holes provided on two lateral lines of the switch part and corresponding to the focusing radioactive source for focused therapy, and a second through hole arranged in middle of the switch part corresponding to the conformal radioactive source for conformal therapy, and the second through hole is offset from a symmetry line of the two rows of first through holes. 12. A collimator assembly comprising: a collimator carrier, and a plurality of focusing collimators and at least one multi-leaf collimator disposed on the collimator carrier, wherein the focusing collimator is provided with a square hole and groups of collimating holes configured for directing the radiation emitted by corresponding radioactive sources, each said group of collimating holes comprises two rows of collimating holes in same aperture diameter, and the apertures size of the collimating holes in different group are different, distance between a center of the square hole to each of the two rows of collimating holes is the same. 13. The collimator assembly of claim 12, wherein the plurality of focusing collimators comprise three groups of collimating holes.