Cylindrical permanent magnet device generating a controlled magnetic field at a distance from the surface thereof

摘要

The cylindrical permanent magnet device includes at least one basic structure (10) having a longitudinal axis (z) and a set (20) of coaxial magnetized structures (21, 22, 23, 24) that are in the form of non-contiguous rings of axis that is the longitudinal axis (z) and that are disposed on the same side of the basic structure (10), defining an exterior surface perpendicular to the longitudinal axis (z) to produce a magnetic field (B0) outside the magnet device in an exterior area of interest (3) situated at a predetermined distance from the exterior surface along the longitudinal axis (z). At least one of the coaxial magnetized structures (21, 22, 23, 24) in the form of rings is divided into components in the form of non-contiguous identical sectors. The basic structure (10) and the set (20) of coaxial magnetized structures (21, 22, 23, 24) in the form of rings are magnetized in the same direction (M) to create in the exterior area of interest (3) an induced magnetic field (B0) that is homogeneous or that has a constant gradient and that is oriented at a predetermined angle (θ2) relative to the longitudinal axis (z).

主权项

1. A cylindrical permanent magnet device applied to a nuclear magnetic resonance device and including a single basic structure having a longitudinal axis and a set of coaxial magnetized structures that are in the form of non-contiguous rings of axis that is said longitudinal axis and that are disposed on the same side of the basic structure, defining an exterior surface perpendicular to said longitudinal axis to produce a magnetic field outside the magnet device in an exterior area of interest situated at a predetermined distance from said exterior surface along the longitudinal axis, the permanent magnet device being characterized in that at least one of the coaxial magnetized structures in the form of rings is divided into components in the form of non-contiguous identical sectors, and the basic structure and the set of coaxial magnetized structures in the form of rings are magnetized in the same direction to create in said exterior area of interest an induced magnetic field that is homogeneous or that has a constant gradient and that is oriented at a predetermined angle relative to said longitudinal axis.