Patent ID: 8860539

Claim:
A magnetized structure applied to a nuclear magnetic resonance device that induces in a central area of interest a homogeneous magnetic field of predetermined orientation relative to a longitudinal axis of the structure, the structure comprising at least first and second magnetized rings disposed symmetrically relative to a plane that is perpendicular to said longitudinal axis and that contains said central area of interest, and at least one median annular magnetized structure disposed at least partly between the first and second magnetized rings and also disposed symmetrically relative to said plane, the first magnetized ring being magnetized radially relative to the longitudinal axis with divergent magnetization, the second magnetized ring being magnetized radially relative to the longitudinal axis with convergent magnetization, and the median annular magnetized structure being magnetized with an orientation different from that of the magnetization of the first and second magnetized rings, the magnetized structure being characterized in that the median annular magnetized structure comprises at least one magnetized ring having a magnetization distribution of orientation that varies as in Halbach dipoles, and in that the first and second magnetized rings and the median annular magnetized structure are each divided into individual components in the form of regularly distributed identical sectors.