公开(公告)号：US20200064424A1

公开(公告)日：2020-02-27

申请号：US16547769

申请日：2019-08-22

Applicant: Bruker BioSpin GmbH

Inventor： Volker NIEMANN ,  Rainer PIETIG

IPC: G01R33/383 ,  G01R33/38 ,  G01R33/3873 ,  H01F7/02

Abstract: A magnet arrangement (1) in a magnetic resonance apparatus having a permanent magnet system for generating a homogeneous magnetic field in a direction perpendicular to a z-axis in a measurement volume. The magnet system has at least two ring-shaped magnet elements (2) in a ring plane, which are arranged coaxially around the z-axis and are constructed from individual magnet segments (3) arranged next to one another in a Halbach configuration. The magnetization direction of at least two ring-shaped magnet elements deviates from the ring plane such that the component perpendicular to the ring plane varies cosinusoidally with the azimuthal angle of the respective ring-shaped magnet element. The magnetization of in each case two ring-shaped magnet elements is mirror-symmetrical with respect to one another, wherein the mirror plane is the central x-y-plane perpendicular to the z-axis. The disclosed arrangement provides a compact and lightweight permanent magnet arrangement for an MR apparatus.

公开(公告)号：US20200166591A1

公开(公告)日：2020-05-28

申请号：US16693832

申请日：2019-11-25

Applicant: Bruker BioSpin GmbH

Inventor： Rainer PIETIG ,  Volker NIEMANN ,  Lukas HAENICHEN

IPC: G01R33/383 ,  H01F7/02

Abstract: A magnet arrangement having a hollow-cylindrical magnet element that has an axial length Lz,M and an inner radius Rin, is constructed from magnet segments arranged concentrically around the z-axis, and has a Halbach magnetization. At least one ring-shaped magnet element has a notched, hollow-cylindrical cutout extending circumferentially around the z-axis symmetrically with respect to the plane z=0, the axial extent Lz,A of the cutout being less than the axial length Lz,M of the magnet element. The cutout has a radial depth TA and an axial length Lz,A