Patent ID: 7960710
Filing Date: 2011-06-14
Classification: A61B,A61N,G01R

Abstract:
1. Particle radiation therapy equipment arranged to apply a charged particle beam, in a predetermined direction, to a region of application, said radiation therapy equipment comprising: a charged particle beam source arranged to direct a charged particle beam in the predetermined direction; and magnetic field generation means for generating a magnetic field in an imaging volume which includes the region of application, at the same time that the charged particle beam is applied; wherein, the magnetic field generation means is arranged to provide access to the region of application, and to provide a homogeneous magnetic field in the region of application, said magnetic field being directed substantially in the predetermined direction; the magnetic field generation means comprises magnetic coils, each comprising windings of electrically conductive material; the magnetic coils are arranged symmetrically about a midplane (XY) and about a plane of reflection (YZ) that is perpendicular to the midplane (XY), such that the magnetic coils have a further plane of symmetry (XZ), which is perpendicular to both the midplane (XY) and the plane of reflection (YZ); each of the coils is wound around an axis that is perpendicular to the midplane (XY); and the windings are configured such that, in operation, current flow is symmetrical about the plane of reflection (YZ) and anti-symmetrical about the midplane (XY), to produce a resultant field at the center of the magnetic field generation means which is perpendicular to the plane of reflection (YZ), parallel to the midplane (XY), and directed substantially in the predetermined direction.