| 摘要 |
A magnetic field generation unit is disposed on one surface side of an object to be detected (4) that has a sheet shape and contains a magnetic component. The magnetic field generation unit is provided with a first magnetic pole part that constitutes a first magnetic pole, and a second magnetic pole part that constitutes a second magnetic pole opposite to the first magnetic pole. The magnetic field generation unit generates a cross magnetic field that crosses the object to be detected (4). An MR element (3) is disposed between the first magnetic pole part and the object to be detected (4). The resistance value of the MR element (3) changes according to the change of a component in a conveyance direction of the cross magnetic field. The position in the conveyance direction of the MR element (3) is a position shifted along the conveyance direction from the center position in the conveyance direction of the first magnetic pole part, and is located between both ends in the conveyance direction of the first magnetic pole part. |
