| 摘要 |
PROBLEM TO BE SOLVED: To reduce magnetic field leakage from gaps between frames and attain both permeability of air and light and excellent magnetic shielding performance, in a transmission magnetic shield structure including a plurality of frames each made of a platelike magnetic plate at intervals in the direction of the platelike magnetic plates. SOLUTION: In the magnetic shield structure; a ratio of the interval d of the frames to a magnetic material width W satisfies 1≤d/W≤20, and a copper wire is wound like a coil around the frame. In a method for the magnetic shield; AC current flows to the coil while a magnetic field to be shielded is applied, thereafter the current is gradually reduced, and finally no current flows. COPYRIGHT: (C)2008,JPO&INPIT
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