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

Abstract

The cylindrical permanent magnet device includes at least one basic structure () having a longitudinal axis (z) and a set () of coaxial magnetized structures () 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 (), defining an exterior surface perpendicular to the longitudinal axis (z) to produce a magnetic field (B) outside the magnet device in an exterior area of interest () situated at a predetermined distance from the exterior surface along the longitudinal axis (z). 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. The basic structure () and the set () of coaxial magnetized structures () in the form of rings are magnetized in the same direction (M) to create in the exterior area of interest () an induced magnetic field (B) that is homogeneous or that has a constant gradient and that is oriented at a predetermined angle (θ) relative to the longitudinal axis (z).