| 摘要 |
A first magnet (6) and a second magnet (7) arranged so that the opposite poles thereof face one another are provided in a wall surface of a hollow section (2) through which paper currency (5) is transported, and thereby form a gradient magnetic field including a zero point both in a magnetic field component in the direction in which the poles face one another between the magnets, and in a magnetic field component in the direction of transport of the paper currency (5) within the hollow section (2). An AMR element (10) is provided between the paper currency (5) and the first magnet (6). The AMR element (10) is enclosed in a multilayer substrate and is clad with a resin. The AMR element (10) is provided in a region of low magnetic field strength near where the magnetic field strength of the gradient magnetic field reaches the zero point in the transport direction. The paper currency (5) passes through a region of high magnetic field strength in the gradient magnetic field. |
