Device for generating a magnetic field for computer-controlled tomography by means of a nuclear magnetic resonance imaging.

摘要

A magnetic field generating device for the NMR-CT comprises a pair of opposing permanent magnet segments (36) magnetically coupled by a yoke (33) which define therebetween an air gap (37) where a magnetic field is created. Each segment has a pole piece (34) attached to its gap-facing surface. Each segment is composed of a ferrite magnet (38) and a rare earth magnet (39), one of the two magnets being disposed in the central portion of the segment and the other disposed around the one magnet. The thickness of the ferrite magnet in the direction of attaching it to the yoke is larger than that of the rare earth magnet.