| 摘要 |
PURPOSE:To easily manufacture a magnetic sensor with large S/N ratio and good stability, by forming the 1st magnetic thin film with less coercive force and the 2nd magnetic thin film with large coercive force on the surface of rod shape nonmagnetic substance with a vacuum thin film technology for both the magnetic films. CONSTITUTION:On the surface of a nonmagnetic substance such as a glass rod, the 1st magnetic substance thin film consisting of 42wt% of Ni, 28wt% of Fe and 30wt% of Co for example, is evaporated under vacuum with the resistive heating evaporation method while rotating the nonmagnetic substance in a magnetic field, and the 2nd magnetic thin film consisting of 17.5wt% of Ni, 52.5% of Fe, and 30% of Co is formed under the identical vacuum. Thus, it is more preferable to constitute the films with the 1st thin film with low coercive force and the 2nd thin film with high coercive force through changing ratio of the contents than to constitute magnetic thin films having different contents. A pickup coil is wound on the outer circumference of the magnetic thin film, allowing to obtain a magnetic sensor generating a large and steep pulse voltage stably with a simple method. |
