Matsushita Electric Industrial Co., Ltd.

Matsushita Electrical Industrial Co., Ltd.

Nobuyuki Kaminaka

Kenji Kanai

Noboru Nomura

Norimoto Nouchi

Mitsuo Satomi

Yuji Omata

Ken Takahashi

Hiroshi Yohda

Satoru Mitani

Seishi Sasaki

Yuuji Omata

Kazuo Nakamura

Hiroshi Youda

Shinzaburo Ishikawa

Tetuo Adachi

Yasuo Yoshida

A magnetic head having head core constituted by a magnetic material sandwiched on both sides thereof by a substrate material and the magnetic material and the substrate materials are bonded by crystallized glass containing crystals such as gahnite, willemite or the like.

Crystallized glass-bonded amorphous metal magnetic film-non-magnetic

A magnetic head having head core constituted by a sandwiched magnetic material on both side thereof by a substrate materials such as, and the magnetic material and the substrate materials are bonded by crystallized glass containing crystals such as gahnite, willemite or the like.

Method of making a crystallized glass-bonded amorphous metal magnetic

A magnetic head for the video tape recorder of azimuth recording type, which features an improved S/N ratio in the overwrite region and assures a high picture quality has a magnetic core for defining a magnetic gap in this head which is made of a plurality of magnetic materials differing in saturation flux density in the direction of track width, with the material having a higher saturation flux density being disposed on the overwriting side of the head. This arrangement permits recording to a greater depth than the depth of magnetization by previous recording to assure an improved picture quality with a higher S/N ratio.

Magnetic head for azimuth recording in a high density magnetic recording

A perpendicular magnetic head of high recording and reproducing efficiency which integrally incorporates a step-up transformer. A main pole for picking up a reproduce magnetic flux from a recording medium and applying recording magnetic field thereto is formed of a magnetic thin film. A signal winding formed of a thin film is disposed in the immediate vicinity of the forward end of the main pole so as to have a high conversion sensitivity per turn with respect to the reproduce magnetic flux from the recording medium. The signal winding which itself constitutes a closed circuit interlinks a magnetic path of the step-up transformer, thereby forming a primary winding of the transformer. A secondary winding from which head output is taken out is wound in the magnetic path of the transformer.

Magnetic head for perpendicular magnetic recording and reproduction

A thin film magnetic head comprising a magnetic core of accumulation layers forming a magnetic circuit and including at least two layers of magnetic film with a particular magnetic characteristic. The constitution of completely covering a magnetic film with a small pattern by a magnetic film with a large pattern makes the edge part smooth because the end of the underlying magnetic film is covered with the upper magnetic film. This edge-smoothing effect appears most pronounced in a manufacturing method in which electrodeposition is used for the formation of magnetic films. By sequentially forming the magnetic films from that of a smaller pattern towards that of a larger pattern, the film formation proceeds at step parts such as end parts of the underlying magnetic films due to the levelling action which is inherent in the electrodeposition method. Such a film formation realizes extremely smooth shielding and yet the pattern formation can be carried out by a single step of photoresist coating to shorten the production process.

Magnetic head comprising a core formed of small and large thin film

A thin magnetic film is deposited over a nonmagnetic or piezoelectric substrate. When a shock wave is propagated through this substrate from its one end to the other end, the permeability of the thin magnetic film is locally increased and a portion or region having a high permeability also travels from one end to the other end of the thin magnetic film in unison with the shock wave. A magnetic core with a signal winding is disposed and magnetically coupled with the thin magnetic film. The signal can be recorded or reproduced while the recording medium is scanned.

Magnetic head having electromechanical transducer disposed at one end

Magnetoresistive thin film head

In a magnetoresistive (MR) effect head, electrodes for supplying a current to an MR element and a bias current conductor are not exposed at a contact surface of the MR head which is brought into sliding contact with a magnetic recording medium, thus preventing surface roughening of the contact surface.

Thin film magnetic head

In a thin film magnetic head in which a lower magnetic layer is formed on a non-magnetic substrate through a non-magnetic layer, and a conductive layer constituting a signal winding and an upper magnetic layer are formed on the lower magnetic layer, the lower magnetic layer is formed within a recess formed in the non-magnetic layer. The recess may pass through the magnetic layer. The lower magnetic layer formed within the recess in the non-magnetic layer can considerably reduce raised portions associated with respective upper layers so that the thin film magnetic head can be improved in magnetic efficienty and yield rate during manufacture.

The invention provides a thin film element which includes a thin film of an organic material, which has a multilayered structure of thin films, and which has a protective film of multilayered structure having films of at least two nonmagnetic materials, or of a thin film of a mixture of at least two nonmagnetic insulating materials. The protective film has a low internal stress, and the step coverage and adhesion strength thereof at edges of the high step portion is excellent.

Thin film element

A thin-film magnetic head having a magnetic substrate made from ferrite, iron-aluminum-silicon alloy or like material, and an upper magnetic layer formed on the magnetic substrate with a lower magnetic layer and a conductive layer interposed therebetween. A portion of the upper magnetic layer is jointed to the magnetic substrate while another portion of the upper magnetic layer is jointed to the lower magnetic layer through a non-magnetic layer of SiO.sub.2 or like material constituting a magnetic gap. The lower magnetic layer, magnetic substrate, upper magnetic layer and the non-magnetic layer in combination form a closed magnetic circuit. A groove is defined between the lower magnetic layer and the magnetic substrate, and formed in the side surface of the magnetic substrate adapted to face a magnetic recording medium. The recess is filled with a non-magnetic material such as glass. Accordingly, it is possible to realize a definite pole piece length to permit an improvement in short-wavelength reproduction characteristics.

Thin-film magnetic head

The invention provides a magnetoresistive element which magnetostatically has magnetic anisotropy to control a domain structure and which eliminates Barkhousen noise that will cause abrupt movement of domain walls and irregular magnetization due to a change in the signal magnetic field, wherein a grating pattern is formed on at least one surface of a magnetoresistive film by a process in which a grating pattern is unidirectionally formed on the surface of a substrate and the magnetoresistive film of a ferromagnetic body is deposited thereon. Further, various magnetoresistive elements to which a novel bias method is applied are provided.

Magnetoresistive element

A thin film magnetic head has a substrate with thin film layers deposited thereon and a protector layer bonded by a bonding layer to the substrate, with the thin film layers interposed therebetween. The thin film layers includes components of an electromagnetic transducing means. The bonding layer is a glass having a working temperature at which a magnetic layer included in the thin film layers does not have the magnetic characteristics deteriorated to any substantial degree. The fusing of the glass for making the bonding layer is performed at a temperature below 450.degree. C.

Thin film magnetic head and method of making it

A magnetic head arrangement includes a spiral coil made of a thin layer and having a central opening. The spiral coil is deposited on a first layer of magnetic material in an electrically insulated manner. The arrangement further includes a second layer of magnetic material having a width wider than that of the central opening of the spiral coil and deposited on the spiral coil in an electrically insulated manner. A portion of the second layer located in the central opening of the spiral coil is magnetically connected with the first layer and another portion of the second layer located outside the spiral coil is held above the first layer to form a predetermined gap.

Growing community of inventors

Moriguchi, Japan

Nobuyuki Kaminaka