Hitachi, Ltd.

Hitachi Maxell, Limited

Toyoji Okuwaki

Noriaki Okamoto

Takeshi Miyazaki

Hiroyuki Suzuki

Hideaki Tanaka

Masaaki Futamoto

Shinichiro Saito

Hideo Fujiwara

Yukio Honda

Yoshinori Takeuchi

Masahiro Ojima

Kazuetsu Yoshida

Yoshiki Kato

Takeshi Nakao

Masaki Ohura

Yuzo Yamaguchi

Kunihiro Maeda

Yoshinori Miyamura

Yokuo Saitoh

Yosuke Seo

Shinsuke Higuchi

Hideo Daimon

Norikazu Tsumita

Kousaku Wakatsuki

Yoshihiko Miyake

Takashi Nishimura

Kazusuke Yamanaka

Takashi Tamura

Osamu Kitakami

Kenichi Gomi

Akihiro Gotoh

Youichi Kawakubo

Nobuo Nakagawa

Yoshiyuki Hirano

Hitoshi Iwata

Shoichi Sawahata

Kazushige Imagawa

Katsuhiko Kato

Katuo Uda

Maki Kondo

Hideo Kusada

A magnetic recording medium having an improved S/N is provided by using a ferromagnetic metal thin film having a mean value of a fluctuation field of magnetic viscosithy measured at 25.degree. C. in a region in which an applied magnetic field strength is 0.8 to 1.2 times as large as a remanence coercivity, of between 15 Oersteads and 30 Oersteads, and preferably a coercivity of between 700 Oersteads and 2000 Oersteads.

Magnetic recording medium

There is provided a magnetic disk apparatus including at least one magnetic disk having a magnetic layer and a surface protective layer on a substrate; a magnetic head which faces the magnetic disk in a rotating state with a micro gap and is supported by a slider; rotating means for rotating the magnetic disk; and magnetic head positioning means for moving and positioning the magnetic head to a predetermined position on the magnetic disk, wherein a plurality of protrusions each having a flat surface are formed in at least a region on the surface of the magnetic disk where a contact start/stop operation can be executed, an area ratio of the protrusions per 1 mm.sup.2 lies within a range from 0.1 to 80%, a height of the protrusion of the maximum height among the protrusions lies within a range from 5 to 40 nm, and the magnetic layer is formed on the whole surface on the base plate. According to the above magnetic disk apparatus, the frictional force between the disk and the head is small, and the floating height of the head can be reduced, and good floating stability is obtained, so that excellent recording and reproducing characteristics are obtained.

Magnetic disk with surface protective layer having convex portions and

The present invention provides; a magnetic disk recorder comprising (i) magnetic disks having magnetic recording media, (ii) thin-film magnetic heads for recording information in the recording media and reproducing information therefrom, and (iii) a carriage for moving the magnetic heads to intended positions, the recorder being wherein the thin-film magnetic heads are formed on sliders and these sliders comprise sintered bodies containing a non-magnetic metal oxide of spinel structure and harder ceramic particles than the metal oxide which are dispersed in the metal oxide; a sintered body useful particularly as a material for the magnetic head slider, a method for making the sintered body, and a magnetic head and a magnetic head slider, for recording and reproducing information, which are made by using the sintered body.

Magnetic recorder provided with a magnetic head slider having a

A magneto-optical memory apparatus has an optical head for applying a light to a substrate of a recording medium such as a magneto-optical disk having a magneto-optical recording film formed on the substrate and continuously applying a high power laser beam in a record mode, and a floating magnetic head arranged on the opposite side of the recording medium to the side of the optical head and adapted to be kept at a substantially constant distance from the recording medium by an air pressure created between the magnetic head and the recording medium by the movement of the recording medium, for applying, in the record mode, a magnetic field which is polarity-inverted or intensity-modulated according to information to be recorded, to the magneto-optical recording film.

Magneto-optical memory apparatus having a floating magnetic head

A magnetic recording medium which comprises a non-magnetic substrate, a magnetic film formed on the substrate and a protective film provided on the magnetic film, the protective film being composed of at least two groups of element, the element in one group being at least one of B and C having a smaller atomic size, and a concentration of the element increasing from the interface side of the protective film with the magnetic film toward the opposite face side throughout the protective film has an improved durability against a magnetic head.

A magnetic disk apparatus using at least one floating magnetic head which is floated above the surface of a rotating magnetic disk by utilizing dynamic pressure of air caused by the rotation of the magnetic disk, the magnetic disk apparatus comprising, a magnetic head assembly including a magnetic head and a supporting device for supporting the magnetic head to float above the surface of the rotating magnetic disk, the supporting device being provided with a space changing device for changing a space between the magnetic disk surface and the magnetic head, a driver coupled with the space changing device for driving the space changing device, and a controller coupled with the driver for controlling the driving of the space changing device by the driver to change the space between the magnetic head and the magnetic disk surface.

Magnetic disk apparatus

Growing community of inventors

Tokyo, Japan

Toyoji Okuwaki