| 摘要 |
PROBLEM TO BE SOLVED: To provide a superconducting magnet device especially suitable as the magnetic field generation source of a magnetic resonance imaging device. SOLUTION: A magnetic pole 12 for generating a disk-like magnetic field is arranged on the inner peripheral side of a main coil 10 forming the magnetic field space 16 of a static magnetic field, the central part of the magnetic pole 12 is connected to the small diameter part 18 of a yoke 14, and the small diameter part 18 is formed in a diameter smaller than that of the magnetic pole 12 by using a ferromagnetic material which is easily saturated magnetically. Thus, in the process that the line of magnetic force generated from the main coil 10 moves from the magnetic pole 12 to the yoke 14 with the yoke 14 as a return circuit, the line of magnetic force is concentrated on the small diameter part 18, the magnetic field inside the magnetic pole 12 is made axially symmetrical without receiving the influence of the magnetic field due to the axis shift of the main coil 10 even when the axis of the main coil 10 is shifted, and as a result the magnetic field inside an imaging area is made axially symmetrical. COPYRIGHT: (C)2005,JPO&NCIPI |
