Method for designing open magnets and open magnetic apparatus for use in MRI/MRT probes

摘要

An open yoked magnetic apparatus for producing a substantially homogenous magnetic field. The apparatus includes an open ferromagnetic yoke, and two complementary permanent magnetic assemblies attached to opposing sides of the yoke. Each magnet assembly includes a ferromagnetic pole-piece and a first magnetic structure disposed between the pole-piece and the yoke, at least one annular ferromagnetic collimator concentric with said pole-piece and radially separated therefrom by a gap, and at least a second magnetic structure radially separated from the first magnetic structure by a gap and disposed between the at least one collimator and the yoke. The magnetic structures may be solid structures made from magnetic material or may be segmented or may include a plurality of magnetic blocks. A method for designing such an open yoked magnetic apparatus with improved properties is also disclosed.