Abstract: A method and apparatus for magnetic recording which permits two information signals to be recorded so that they overlay one another. The first and second tracks cross each other without generating crosstalk during reproduction of the two information signals.

Abstract: A magnetically recorded signal on a magnetic recording medium is reproduced in response to a magnetic field produced thereby by applying a DC biasing magnetic field along the magnetic path of the core of a coil-supporting magnetic head, and adding a high-frequency magnetic field of a small amplitude to the DC biasing magnetic field. The DC biasing magnetic field is produced by passing a DC biasing current through a DC biasing coil on the core, and the high-frequency magnetic field is produced by passing a high-frequency current through another coil on the core.

Abstract: In a system for reproducing magnetically recorded information, a magnetic recording medium is moved in contact with a gap of a magnetic circuit. A light beam is linearly polarized and is made to impinge upon a magnetic layer of an inductive type magnetic thin film head for detecting the recorded information on the basis of a change in internal magnetization so that the light beam is incident obliquely with respect to the magnetic layer in a plane approximately parallel to the direction of internal magnetization of the magnetic layer and approximately normal to a substrate of the magnetic thin film head. The light beam reflected by the magnetic layer is detected, and the direction of the internal magnetization is detected on the basis of the rotation angle of the plane of polarization of the reflected light beam.

Abstract: A light beam is made to impinge upon a light reflecting section of a magnetic head provided with a magnetic layer having the light reflecting section on the surface. A change in characteristics of the light beam reflected by the light reflecting section, which is caused by the Kerr effect in accordance with a change in internal magnetization of the magnetic layer, is detected photoelectrically. Magnetic characteristics of the magnetic head are measured on the basis of the detected change in characteristics of the reflected light beam.

Abstract: A magnetic device comprised of a soft magnetic thin film having uniaxial magnetic anastropy is achieved by depositing a first permalloy material on a substrate in a pattern having a plurality of small rectangular elements each of which will function as a small bar magnet due to shape anisotropy and depositing a second permalloy film over the remainder of the substrate which will have uniaxial anisotropy due to the magnetic field of each small bar magnet.