MRI MAGNETIC FIELD GENERATOR

摘要

An object of the present invention is to provide an MRI magnetic field generator with which the magnetic field uniformity within the imaging field of view of the air gap can be adjusted easily and safely, without having to detach the gradient coils, after the MRI magnetic field generator has been installed with gradient coils already mounted on a pair of magnetic pole pieces. After the holder disk 13 has been placed on and fastened to the base disk 11, the magnetic material pellets or permanent magnet pellets for adjusting the magnetic field uniformity are inserted into the required pits disposed in a specific pattern, and if needed, spacers are placed in the gaps between Äthe pelletsÜ and the cover disk 14 to position everything, after which the cover disk 14 is screwed onto hold everything together. The resulting shim holder 10 is aligned with and fastened to the gradient coil 6 or its support member.