磁気シールド材料の内部磁界を考慮したボックスシールドの性能推定法とその精度検証

抄録

Magnetoencephalographs (MEGs) are highly sensitive to micromagnetic noises, and thus, a high performance magnetically shielded room (MSR) is essential. The shielding effect of a novel MSR should be predicted to verify if it satisfies the required specifications of the MEG at the design stage. Therefore, an accurate prediction method based on the properties of shielding materials and shape of the MSR is necessary. We examined four types of method to estimate µ and to predict the shielding effect. To verify the prediction accuracy, we estimated µ of a permalloy at very small magnetic field strength and predicted the shielding effect of a box-shaped shield, as simple examples, and compared the obtained result with the experimental result. The result of this study shows that some of the prediction methods have an error of less than 70% comparing with the experimental result.