Permanent magnet ring assembly for NMR imaging system and method for using such assembly
Patent
·
OSTI ID:5843152
In an NMR imaging system, an apparatus is described for producing a homogeneous transverse magnetic field in a predetermined volume comprising: (a) a ring assembly having an axial extent L defined by non-magnetic rings, each having an axis and positioned side-by-side so that axis of the rings are colinear and define the axis of the ring assembly; (b) discrete, permanent magnet segments angularly mounted within each ring for defining a central, coaxial aperture; (c) each segment in each ring having the same angular position and the same easy axis of magnetization whose orientation is functionally related to the angular position of the segment in the ring; (d) each segment having inner and outer free ends that are nominally located at distances r1 and r2, respectively, from the axis of the ring within which it is mounted, the inner free ends of the segments of all the rings defining a central aperture of length L within the ring assembly; and (e) means for mounting the segments in each ring such that the distances r1 and r2 of each segment are nonuniformly but functionally related to the axial extent L of the assembly so as to produce a homogeneous magnetic field transverse to the axis of the ring assembly.
- Assignee:
- Elscint Ltd., Haifa
- Patent Number(s):
- US 4703276
- OSTI ID:
- 5843152
- Country of Publication:
- United States
- Language:
- English
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