摘要 |
<P>PROBLEM TO BE SOLVED: To measure a magnetic field vector without contacting which is generated in the cases that an electric current field exists inside a sample previously, that electric current flows directly and that eddy current is induced by applying a magnetic field, to determine a distribution of current density vectors in an interested space or an interested region, and thereby to determine a distribution of the conductivity in the interested space or the interested region. <P>SOLUTION: The distribution of current density vectors is determined by solving an integral equation (i.e., Biot-savart law) in the interested space or the interested region being described by data of the magnetic field around the sample which is measured by a non-contact detector such as a device for detecting the magnetic field vector or the like employing detecting elements and array-type elements for detecting magnetism, static magnetic field or electromagnetic wave. Then the relative distribution of conductivity in relation to a referential conductivity being set in the interested space or the interested region is estimated by solving a first spatial partial differential equation being described by current data. <P>COPYRIGHT: (C)2003,JPO |