METHOD FOR DETERMINING WOUND WIRE SHAPE OF GRADIENT MAGNETIC FIELD GENERATING COIL

摘要

PROBLEM TO BE SOLVED: To make it possible to appropriately determine the wound wire shape of a flat surface type gradient magnetic field generating coil, to be applied to an open type MRI magnet, which generates a high linear gradient magnet field, by a method wherein a plurality of magnetic field setting points are set in the vicinity of the surface of a specified spherical region, and undetermined constants are calculated by using the coordinates of the magnetic field setting points. SOLUTION: When the radius of a photographing region where a gradient magnetic field is planned to be generated is taken to be R1, and distances from the center O of the photographing region to arrangement planned locations of a main coil 2a and a shield coil 2b are taken to be a1, a2, 0R1a1a2 is satisfied. The, in the vicinity of the surface of the photographing region, (n) points of magnetic field setting points are set with approx. equal intervals facing the vertical symmetrical axis R. Then, undetermined constants are calculated by using the coordinates of the magnetic field setting points, and by using the undetermined constants, continuous current density distributions of the main coil 2a and the shield coil 2b are calculated. Then, the continuous current density distributions of the main coil 2a and the shield coil 2b are respectively digitized, and the shapes of the main coil 2a and the shield coil 2b are determined.