| 摘要 |
PROBLEM TO BE SOLVED: To provide a method and a system for shimming an MRI magnetic field generating assembly. SOLUTION: A plurality of shims 18, at least, partially compensating non-uniformity of a magnetic field generated by the magnetic field generating assembly 12 are disposed along a plurality of concentric geometric shapes 52 each having at least five sides. In another mode, the shims are disposed in a plurality of lateral lines and vertical rows with the lateral lines orthogonally crossing with the vertical rows. In another mode, at least, one of the shims is a magnetic flat plate including an upper surface edge 80, a bottom surface edge 82, side surface edges 84 and 86, and face surfaces 88 and 90. The bottom surface edge is positioned in a proximal part of the flat plate relatively to the magnetic field generating assembly, the upper surface edge is a distal part of the flat plate from the magnetic field generating assembly, and the face surfaces are aligned in the direction of the magnetic field to be generated by the magnetic field generating assembly. COPYRIGHT: (C)2004,JPO
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