Nippon Telegraph and Telephone Corporation

Yasuhiro Koshimoto

Osamu Ishii

Masakatsu Senda

Tomoyuki Toshima

Toshinori Mori

Electromagnetic noise absorbing material and filter, which are small, light, and effective even with respect to unwanted electromagnetic waves of a few hundred MHz or more, are provided. A small and flexible electromagnetic noise filter cable and tape-shaped electromagnetic noise filter, as well as a manufacturing method and manufacturing apparatus therefor, are also provided. The electromagnetic noise absorbing material has a thickness or particle diameter of the alloy magnetic substance which is within a range of from 1/10 to 10 times the skin depth thereof, and thereby, a large eddy current loss can be generated, so that it is possible to manufacture electromagnetic noise filters having various shapes, which are small, light, and which realize a large electromagnetic noise suppression effect as a result of eddy current loss, and these possess a large relative magnetic permeability even at levels of a few hundred MHz or more. According to the thin film manufacturing method and apparatus, it is possible to easily manufacture an electromagnetic noise absorbing material having small hysteresis, possessing a hard axis of uni-axial magnetic anisotropy, which is superior in high-frequency response, and has a large electromagnetic noise suppression effect.

Electromagnetic noise absorbing material and electromagnetic noise filter

In a magnetic field sensing method in accordance with the invention of the present application, a magnetic sensor comprising a conductor and at least one magnetic material provided on any of the surfaces of this conductor, is employed. This magnetic sensor is disposed in the vicinity of an external magnetic field which is to be sensed, and by means of supplying a high frequency current to this conductor, the impedance of the conductor changes in accordance with the external magnetic field, and based on this, the external magnetic field is sensed.

Magnetic sensor and magnetic field sensing method using said magnetic

Magnetic head, magnetic recording method using the magnetic head, and

Magnetic sensor and magnetic field sensing method of using same based on

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Higashiyamato, Japan

Yasuhiro Koshimoto