| 摘要 |
PROBLEM TO BE SOLVED: To provide a magnetic field detection device which detects a fine magnetic field variation with a magnetism detection element unsaturated, and also detects a magnetic field variation more efficiently by concentrating an eddy current into a fine part of an inspection object. SOLUTION: In this magnetic field detection device for detecting a magnetic field generated from the inspection object 13 of a non-magnetic conductor to which an excitation magnetic field 11 is applied by an eddy current detection system, a figure-eight-shaped coil 1 comprising a thin film pattern or a wire rod is used as an excitation coil for generating the excitation magnetic field 11, and the eddy current is concentrated into the fine part 12 of the inspection object 13, and the magnetic field variation at the fine part 12 is detected. A single-shaft magnetism detection element 2 is arranged so that the magnetism detection direction is orthogonal to the direction of the excitation magnetic field 11, relative to the direction of the excitation magnetic field 11 by the figure-eight-shaped coil 1, thereby to detect only a generated magnetic field in the direction orthogonal to the excitation magnetic field 11 from the fine part 12. COPYRIGHT: (C)2007,JPO&INPIT
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