Fig. 2: Magnetization modes and magnetic field characteristics.

a Magnetic field of an axial dipole magnet. b Magnetic field of a radial dipole magnet. c Magnetic field of a multipole magnet. d Relationship between magnetic field and thickness at the center of the axial magnet. e Relationship between magnetic field and thickness at the center of the radial magnet. f Magnetic field distribution along a cutline of a multipole magnet. g Categories of magnetization modes. h Method for measuring magnetic field signals. i Magnetic field signal data.