| 摘要 |
PURPOSE:To obtain a uniform high frequency magnetic field by a method wherein a heterogenous metal of symmetrical structure having high resistance is provided at the symmetrical position in the vicinity of the intermediate point of a high frequency coil, thereby enabling to almost equalize the current of each coil. CONSTITUTION:A heterogenous metal (stainless steel for copper, for example) of symmetrical structure is inserted in the crossing point 3 located in the vicinity of the intermediate point of an oval coil 1, the RF current which forms an RF magnetic field by the resistance value of the heterogenous metal is controlled, and the symmetrical property of the device is maintained. Instead of the heterogenous metal, the resistance value of the coil 1 may be increased by reducing the cross-sectional area of the coil 1. The insertion of the coils 1 and 2 into the part in the vicinity of terminals 4, 5, 6 and 7 is inappropriate due to having adverse effect of the irregularity, asymmetrical structure and floating capacitance of the part located in the vicinity of the terminals. According to this constitution, the current of each coil can be equalized, thereby enabling to obtain the uniform high frequency magnetic field. |
