MAGNETIC FIELD IN MRI YOKELESS DEVICES: ANALYTICAL APPROACH

This paper presents a three-dimensional analytical expressions for studying the static magnetic fleld produced by Magnetic Resonance Imaging structures. This medical imaging technique uses a very high and uniform magnetic fleld produced by ring permanent magnets with rotating polarizations. However, the manufacturing of such ring permanent magnets is di-cult to realize. Consequently, such ring permanent magnets are replaced by assemblies of tile permanent magnets uniformly magnetized. Unfortunately, the magnetic fleld produced by these tile permanent magnets uniformly magnetized is both less important and less uniform than the one produced by an idealized ring permanent magnet. We propose in this paper to study the in∞uence of the number of tile permanent magnets used on the magnetic fleld properties.