| 摘要 |
PURPOSE: To compare output data of magnetic field detective means of plural living bodies with the magnetic field distribution data calculated from a current source located in a postulated position, to change position, direction and size of the current and to calculate them until function values evaluating their adaptabilities are in predetermined ranges to accurately detect the positions. CONSTITUTION: In order to detect a brain magnetic field, output of a primary differential gradiometer is received (a2), at the same time, output of each combination of magnetic noise detective means is received (a3), and based on these outputs, output of an assumed differential gradiometer is calculated (a4). The detective coils, for example, are 64 channels, and reference coils are 3 in all. When setting the output of channel coil as Sk, output of reference coil as Sj, weight of substraction as ξ, the output Skp of the detective coil, which is so revised as the assumed differential gradiometer is constituted by calculation, equals to SK-Σξkj.Sj, namely, Skp=SK-Σξkj.Sj a suitable weight of substraction ξkj is determined and the substraction of the detective coil is calculated. |
