| 摘要 |
<p>PROBLEM TO BE SOLVED: To make it possible to design a compact self-shielding coil that is excellent in approximate accuracy, simple in construction and large in inside diameter. SOLUTION: This method of design comprises a step of optimizing the position of an internal coil by setting or resetting the number and the number of turns of the internal coil of close coiling so that the coil may fall within a tolerable range of intended magnetic-field gradient intensity under the shielding condition, a step of calculating Fourier components of current distribution needed for an external coil, a step of approximating the Fourier components of current distribution by optimizing the position of the external coil, a step of calculating the leakage magnetic field of the internal and external coils and calculating a distortion of magnetic field due to eddy currents occurring therefrom, and a step of resetting the number of the external coil and the number of turns of the internal and external coils when the leakage magnetic field does not fall within a tolerable range.</p> |
