| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a marker coil generating a magnetic field distribution with a small estimated position error. <P>SOLUTION: The marker coil is used for measuring a magnetic field generated by a subject and comprises a magnetism sensor array for measuring magnetism and coils attached to the subject and generate magnetism measured by the magnetism sensor array. The marker coil has at least two or more coils that are arranged on a plane and generate magnetic fields with opposite directions. The marker coil carries out measurement of magnetic fields by means of the magnetism sensor array using a point where a change rate of magnetic fields generated by the coils is large. <P>COPYRIGHT: (C)2009,JPO&INPIT |
