| abstract |
[Object] To enable reliable detection of a minute magnetic body and enable omission-free detection with respect to detection of foreign substances of a minute magnetic body mixed at a state where positions and orientations in an inspected object are unspecific. n [Solution Means] n A minute magnetic body detecting sensor includes a magnetic impedance element 1, with two magneto-sensitive bodies 11 and 12 disposed in substantially two-dimensional directions such that an angle formed by respective sensitive axes s is substantially 90 degrees, and a signal processing device 2, including a signal processing circuit 20, processing and amplifying damped oscillating voltages output by the two magneto-sensitive bodies 11 and 12 that detected a local magnetic field due to a minute magnetic body that is a foreign substance, two square operating elements 21, squaring output signals m1 and m2, an adder 22, adding the squared signals m1 2 and m2 2 , and a square root operating element 23, performing square root computation on the addition output and outputting a square root output ms, and enables high-precision detection of the existence or non-existence of a minute magnetic body without detection overlooking. |