Mitsubishi Denki Kabushiki Kaisha

Kazuo Hashima

Kazuhiko Tsutsumi

Takashi Tokunaga

Yuji Kawano

Tatsuya Fukami

Yoshiyuki Nakaki

Yoshio Fujii

Motohisa Taguchi

Hiroshi Kobayashi

Shinji Tanabe

Hiroshi Shibata

Yukari Toide

Hiroshi Sugahara

Yuzou Ohdoi

A magneto-optical recording medium wherein an initializing layer is covered with a resin layer for dissipating heat from the initializing layer thereby to prevent signal degradation at high recording power and thus excellent in record/reproduce repetition times, and the initializing layer is compositionally modulated thereby to broaden allowable ranges for the recording/reproducing light intensity and for the external magnetic field, besides the composition of a first or a second magnetic layer is controlled thereby to enhance recording sensitivity, and the exchange-coupling force between the first and second magnetic layers or the magnetic field strengthe to reverse the magnetization of the first magnetic layer is controlled thereby to enhance the recording/reproducing characteristics.

Magneto-optical recording medium and method of manufacturing the same

A magneto-optical recording medium wherein an initializing layer is covered with a resin layer for dissipating heat from the initializing layer thereby to prevent signal degradation at high recording power and thus excellent in-record/reproduce repetition times, and the initializing layer is compositionally modulated thereby to broaden allowable ranges for the recording/reproducing light intensity and for the external magnetic field, besides the composition of a first or a second magnetic layer is controlled thereby to enhance recording sensitivity, and the exchange-coupling force between the first and second magnetic layers or the magnetic field strengthe to reverse the magnetization of the first magnetic layer is controlled thereby to enhance the recording/reproducing characteristics.

A magnetic thin film memory wherein the memory is composed of magnetic thin films with a layer of a higher coercive force and a layer of a lower coercive force via a nonmagnetic layer laminated repetitively, or magnetic thin films having the easy magnetization axis which lies between the perpendicular and the horizontal directions of the magnetic thin film, and information is recorded on the layer of a lower coercive force, or information is recorded by changing the direction of the magnetization by means of a magnetic field applied by two recording lines which cross the magnetic thin film, thereby to obtain a sufficient amplitude of reproduction signal even when the size of the memory is reduced.

Magnetic thin film memory

An information storage system for recording and reproducing information by use of irradiating light on a medium capable of overwriting information is provided. The information storage system is capable of recording information even if the light intensity is varied so as to enhance reliability. The intensity of the light at the time of overwriting is modulated, the more intense light intensity being P.sub.H and the less intense light intensity being P.sub.L. The system includes a mechanism to keep relationship of P.sub.H +.alpha.P.sub.L equal to a constant (.alpha. being a constant depending on the recording conditions). The laser drive circuit is so adjusted that P.sub.H and P.sub.L always provide an optimal condition even if P.sub.H and/or P.sub.L vary. Thus recording can always be performed under optimal conditions to enhance the reliability of the information storage system to expand the power margin of a recording medium and to increase the percentage yield of information medium.

Information storage system

A magneto-optical recording medium comprises a dielectric film disposed on a substrate and formed, for example, of silicon nitride, of for example, 65 nm thickness, a magnetic film disposed on the dielectric film, and formed, for example, of, rare earth-transistion metal alloy thin film, of, for example, 35 thickness, and a reflective film disposed on the magnetic film, and formed of titanium nitride, by, for example, sputtering.

Growing community of inventors

Amagasaki, Japan

Kazuo Hashima