| 摘要 |
The magnetic structure has a pair of spaced apart magnetized elements having surfaces in a common plane that defines a wall of a cavity. The space between the first and second magnetized elements (S1, S2) is formed with at least one slit extending perpendicularly to the common plane. In order to compensate for field distortion in the cavity, a magnetized element is provided in at least one of the slits, the material in the slit having a remanence that is different from the remanences of the spaced apart magnetized elements that define the structure. The field distortion may be compensated by including at least one component in the cavity that has a high magnetic permeability. This component, has a variable thickness. It may be formed of a single component, or of a plurality of plates. In a method for compensating for field distortion in a magnetic structure that defines a cavity, the magnetic field on a surface is measured to produce a map of the field on the surface. A plurality of points on the surface are projected to corresponding points on a second surface. A dipole is applied at each such point on the second surface that cancels perturbations of the magnetic field of the magnetic structure at the respective first point. <IMAGE> |
