PROBLEM TO BE SOLVED: To provide a magnetic field adjustment method capable of highly accurately determining positions to arrange magnetic body pieces and an amount thereof.SOLUTION: In a magnetic field adjustment method for a magnetic field generator having a superconducting coil for generating a static magnetic field and a shim tray in which magnetic body pieces for adjusting magnetic homogeneity of a static magnetic field in a predetermined space are arranged in a plurality of positions, intensity of magnetization of the magnetic body pieces assumed to be positioned in respective predetermined positions is obtained for each predetermined position (S13), and the amount of the magnetic body pieces arranged in respective predetermined positions is calculated by using the magnetization intensity obtained for each predetermined position (S3). To obtain the intensity of magnetization (S13), the intensity of a static magnetic field is calculated for each predetermined position (S11), and the intensity of magnetization is obtained for each predetermined position based on the magnetic field intensity by using database D1 of magnetization characteristics by which the intensity of magnetization relative to a magnetizing force can be determined (S13). Furthermore, the intensity of an additional magnetic field created by magnetic substances arranged to surround the magnetic field generator may also be calculated for each predetermined position and added to calculate the intensity of a static magnetic field for each predetermined position.COPYRIGHT: (C)2014,JPO&INPIT【課題】高精度に磁性体片を配置するべき位置及び量を決定できる磁場調整方法を提供する。【解決手段】静磁場を発生させる超電導コイルと、所定空間における静磁場の磁場均一度を調整するための磁性体片を複数の所定箇所に配置するシムトレイとを有する磁場発生装置の磁場調整方法において、所定箇所毎にそこに配置したと仮定した磁性体片の磁化強度を求め(S13)、所定箇所毎の前記磁化強度を用いて、所定箇所毎に配置する磁性体片の量を計算する(S3)。磁化強度を求める際(S13)には、所定箇所毎に静磁場の磁場強度を計算し(S11)、磁化力に対して磁化強度を決定できる磁化特性のデータベースD1を用い、磁場強度に基づいて、所定箇所毎の磁化強度を取得する(S13)。さらに、磁場発生装置の周囲に設置される磁性体が作る磁場の、所定箇所毎における追加磁場強度を計算し、所定箇所毎に追加磁場強度を静磁場の磁場強度に加算してもよい。【選択図】図6
