Patent ID: 8384387
Filing Date: 2013-02-26
Classification: G01R,H01F

Abstract:
1. A magnetic resonance imaging device comprising: a primary magnet, said primary magnet generating a primary field through a patient-receiving portion therethrough, said primary field containing inhomogeneities within the patient-receiving portion and fringe fields outside thereof; a secondary magnet, said secondary magnet generating a secondary field, said secondary field substantially countering said fringe fields produced by said primary magnet outside of the patient-receiving portion; and at least one correction magnet, said at least one correction magnet substantially correcting said inhomogeneities and substantially straightening field lines associated with said primary field within said patient-receiving portion, thereby improving field uniformity, wherein said primary magnet comprises a first upper coil and a second lower coil, and wherein said at least one correction magnet comprises respective at least one upper corrective coil and at least one lower corrective coil, wherein the distance between said first upper coil and said second lower coil is greater than the distance between said at least one upper corrective coil and said at least one lower corrective coil.