| 摘要 |
<p>PURPOSE:To save the amount of magnet employed and generate a magnetic field excellent in uniformity by a method wherein the widths of end part side small bipole rings are made larger than those of the central parts of the small bipole rings likewise the gaps between the small bipole rings on the end part side are made wider than those on the central part side. CONSTITUTION:A dipole ring 40 is composed of multiple (eight each) small dipole rings 20, 22, 24, 26, 30, 32, 34, 36 divided in the direction perpendicular to the central axis (Z-axis). The right side small dipole rings 20, 22, 24, 26 are arranged symmetrically to the left side small dipole rings 30, 32, 34, 36 centering on the middle point 42 (on the Z-axis) of the dipole ring 40. At this time, the width of end part side small bipole rings are made larger than those of the small bipole rings on the central part side likewise the gaps between the small bipole rings on the end part side are made wider than those on the central part side. Through these procedures, the continuous density changes of the magnetic moment can be excellently approximated so that the magnetic field may be equalized while effectively cutting down the applicable magnet consumption.</p> |
