Abstract: A magnet array (700) includes multiple magnet rings (711-720) and a frame. The multiple magnet rings are positioned along a longitudinal axis and coaxially with the longitudinal axis, wherein at least one (712, 713, 719) of the magnet rings possesses rotational symmetry and has both a finite component of magnetization along an azimuthal (?) coordinate, and a finite magnetization in a longitudinal-radial plane. The multiple magnet rings configured to jointly generate a magnetic field along a direction parallel to the longitudinal axis. The frame is configured to fixedly hold the multiple magnet rings in place.

Abstract: A magnet array includes multiple magnet elements made of a permanent magnet material and a frame. The multiple magnet elements are dispersed around a longitudinal axis. At least some of the magnet elements form a ring which is coaxial with the longitudinal axis. The ring comprises at least one magnet element which possesses a cylindrical symmetry around its own axis of symmetry, wherein the axis of symmetry has a component in a direction tangential to the peripheral shape of the ring. The magnet elements are configured to produce a uniform magnetic field inside an inner predefined volume. The frame is configured to fixedly hold the multiple magnet elements in place.

Abstract: A magnet array includes multiple magnet rings and a frame. The multiple magnet rings are positioned along a longitudinal axis and coaxially with the longitudinal axis, wherein at least two of the magnet rings include mixed-phase magnet rings that are phase-dissimilar. The multiple magnet rings are configured to jointly generate a magnetic field along a direction parallel to the longitudinal axis of at least a given level of uniformity inside a predefined inner volume. The frame is configured to fixedly hold the multiple magnet rings in place.

Abstract: A magnet array includes multiple magnet rings and a frame. The multiple magnet rings are positioned along a longitudinal axis and are coaxial with the longitudinal axis. At least one of the magnet rings encircles a predefined inner volume. A minimal inner radius of the magnet rings positioned on one side of a center of the inner volume along the longitudinal axis is different from the minimal radius of the magnet rings positioned on the other side of the center of inner volume. The magnet rings are configured to jointly generate a magnetic field of at least a given level of uniformity inside the inner volume. The frame is configured to fixedly hold the multiple magnet rings in place.

Abstract: A magnet array includes multiple magnet rings and a frame. The multiple magnet rings are positioned along a longitudinal axis and coaxially with the longitudinal axis, wherein at least one of the magnet rings possesses rotational symmetry and has both a finite component of magnetization along an azimuthal (?) coordinate, and a finite magnetization in a longitudinal-radial plane. The multiple magnet rings configured to jointly generate a magnetic field along a direction parallel to the longitudinal axis. The frame is configured to fixedly hold the multiple magnet rings in place.