The magnetization direction in which the magnetic field becomes the strongest on one axis is derived by the spherical coordinate system. It was found that the magnetic field was strongest at the top and bottom on the axis, and was weakest at the 0 points on the axis. Therefore, it is indicated that there is an optimal division instead of equality when segmenting. Based on the direction of magnetization of the spherical coordinate system, the direction applied in the cylindrical coordinate system and the orthogonal coordinate system is shown. For Halbach sphere and Halbach cylinder, the magnetic field is shown. This magnetization direction is the guiding principle of the design of the magnetic field source, for example, magnetic drag targeting systems and MRI devices. This can be applied not only to the design of magnetic field sources of permanent magnets, but also to the design of electromagnets and superconducting electromagnets.
J-STAGEがリニューアルされました！ https://www.jstage.jst.go.jp/browse/-char/ja/
