| 摘要 |
A magnetic field sensor for gradient field detection (gradient type magnetic field sensor) cancels relatively uniform disturbance magnetic fields (background magnetic fields) such as the terrestrial field through the use of two magneto-impedance elements, thereby making it possible to detect only a signal magnetic field (gradient field) which is considerably localized spatially. The magnetic field sensor includes a pair of sensor heads (A) made of an amorphous wire (1), and a self-oscillation type electronic circuit (B) for detecting a spatially uniform magnetic field or a differential value of a spatially gradient magnetic field by switching the direction of a bias magnetic field applied to the pair of sensor heads (A). <IMAGE> |
