| 摘要 |
PROBLEM TO BE SOLVED: To reduce a level of a magnetic field gradient in a radial direction as well as in an axial direction in a magnetic shield device in which a magnetic field generating coil is installed in the axial direction only of a magnetic shield.SOLUTION: A magnetic shield device includes: a cylindrical shield portion constituted of a magnetic body; and a first coil provided on the same plane as one opening surface of the shield portion or at a position opposite to the opening surface. In an excited state, the first coil reduces a level of a magnetic field gradient in a radial direction inside the shield portion while also reducing a level of a magnetic field gradient in an axial direction inside the shield portion. |
