| 摘要 |
PURPOSE:To enable the determination of the position of current dipole by determining a differentiated value of a discrete magnetic distribution to obtain the position of the current dipole based on the position of an intersection from which the magnetic distribution extending in directions different from each other. CONSTITUTION:The bottom surface 30a of a Dewar 30 is pressed onto a chest wall 39 near the heart to measure a magnetic distribution in a plane along the chest wall 39. Here, when the magnetic distribution is differentiated along direction (x), edge lines 44 and 45 are determined so as to make the differentiated value zero. By differentiating the magnetic distribution along the direction (y), the edge line 46 is determined so as to make the differentiated value zero. The intersection 42 of the edge lines 44 and 46 and the intersection 43 of the edge lines 45 and 46 are determined to obtain the position of a current dipole as midpoint of the two intersections 42 and 43. The depth at which the current dipole exists can be determined depending on a distance (d) between the two intersections 42 and 43. Thus, the position of the current dipole can be determined simply and quickly. |
