Kabushiki Kaisha Toshiba

Katsutaro Ichihara

Keiichiro Yusu

Akira Kikitsu

Sumio Ashida

Toshihiko Nagase

Naomasa Nakamura

Akiko Hirao

Hideyuki Nishizawa

Takayuki Tsukamoto

Junichi Akiyama

Kazuki Matsumoto

Kenji Todori

Noritake Oomachi

Noritake Ohmachi

Michiko Okubo

Tsukasa Nakai

Kohichi Tateyama

Nobuaki Yasuda

Hideo Ogiwara

Hitoshi Iwasaki

Hiroaki Yoda

Yoshiaki Saito

Tomoyuki Maeda

Tadashi Kai

Tsutomu Tanaka

Ryo Sakai

Hisashi Yamada

Takashi Kawakubo

Takashi Ishigami

Naoki Morishita

Koichiro Inomata

Genichi Hatakoshi

Keiji Horioka

Katsumi Suzuki

Naoko Kihara

Naoyuki Inoue

Yoichiro Tanaka

Takashi Hikosaka

Atsuhito Sawabe

Ryoichi Ohara

Kenya Sano

Futoshi Nakamura

Nobuhisa Yoshida

Kuniyoshi Tanaka

Yumi Mizusawa

Hideo Sugai

A phase-change optical recording medium has a recording film that brings about reversible phase-change between a crystalline phase and an amorphous phase upon irradiation with light and an interface film formed in contact with at least one surface of the recording film and comprising hafnium (Hf), silicon (Si), oxygen (O) and carbon (C).

Phase-change optical recording medium

The optical information recording medium according to the present invention includes a transparent substrate having a first surface and a second surface, a recording layer that is arranged on the first surface of the transparent substrate, and a reflection layer arranged on the second surface of the transparent substrate. A hologram is recorded in the recording layer when a signal light and a reference light are incident from an incident side opposite to the transparent substrate. An optical density of the recording layer corresponding to the signal light decreases from the incident side toward the transparent substrate.

Optical information recording medium for holographic recording and method of holographic recording in optical information recording medium

A phase change recording medium comprising an as-deposited first recording layer configured to undergo a reversible phase change between an amorphous state and a crystalline state due to light irradiation and thereby change an optical characteristic. The as-deposited first recording layer includes a plurality of fine nuclei having an average size of 0.5 nm to 4 nm in the amorphous state.

Information recording medium and its manufacturing method

Provided is a holographic recording medium including a recording layer in which information is to be holographically recorded, and a light-shielding layer which faces a main surface of the recording layer. The transmittance of the light-shielding layer for a recording light is increased on increasing intensity of the recording light. Alternatively, the light-shielding layer selectively transmits the recording light.

Holographic recording medium

A phase-change optical recording medium includes a phase-change optical recording film that permits reversible phase change between a crystalline phase and an amorphous phase upon irradiation with light, and an interface film formed of hafnium oxide, or a mixture of hafnium oxide and at least one oxide selected from the group consisting of cerium oxide, titanium oxide and zirconium oxide, and formed in contact with at least one surface of the phase-change optical recording film.

A phase-change optical recording medium has a phase-change recording film to which recording and erasure can be reversibly performed by irradiation with light, and at least one dielectric film formed of a SiOC film containing Si, O and C, and having a carbon concentration within a range of between 0.1 and 30 atomic %.

A tool attachable to a spindle of a machine tool in the same way as an ordinary tool, capable of being driven without connecting with an external power supply etc., giving a higher rotational speed than that of the spindle of the machine tool without supplying electric power from the outside, and able to be changed automatically, provided with a machining tool for machining a workpiece, a motor for driving the machining tool, a generator for generating electric power to drive the motor by the rotation of the spindle, and a breaker for breaking a supply line of electric current from the generator to the motor when electric current over a predetermined value flows in the supply line.

Optical recording medium having super resolution layer

An optical recording medium includes an optical recording layer, a separating layer formed on a reproducing light incident side of the optical recording layer, and a phase-change reproducing layer formed on the reproducing light incident side of the separating layer, absorbance of which phase-change reproducing layer is changed depending on whether a state of the optical recording layer is a recording mark or a space. A transfer portion to which a state of the optical recording layer is transferred is formed in a portion having high absorbance of the phase-change reproducing layer by irradiation with reproducing light, while a portion of the phase-change reproducing layer other than the transfer portion is kept in a state optically differing from the transfer portion.

Optical recording medium and optical recording-reproducing method

An optical information recording medium of this invention includes a substrate, a light incident surface, a first reflecting layer formed between the substrate and the light incident surface, a second reflecting layer formed between the first reflecting layer and the light incident surface and stacked on the first reflecting layer, the second reflecting layer being made of the same material as that of the first reflecting layer, and a phase change optical recording layer formed between the second reflecting layer and the light incident surface, the phase change optical recording layer transiting between a crystal state and an amorphous state when irradiated with a light beam.

Optical information recording medium

A holographic recording medium includes a transparent layer having a servo surface and a light incidence surface which face each other; a reflecting layer formed on the servo surface-side transparent layer; and a holographic recording layer formed on the light illuminating-side transparent layer. The transparent layer includes resin films laminated so that adjacent resin films differ in stretching direction by 90 degrees.

Holographic recording medium and holographic recording medium manufacturing method

An optical disk from which recorded data are read out by means of light irradiation has a substrate having recording pits as data on a surface thereof, and stacked films formed on the substrate. The stacked films contain a super-resolution film of a polymer matrix and semiconductor particles having an organic group covalently bonded thereto, and a reflective film reflecting light. The super-resolution film and the reflective film are provided in this order from a light incident side.

Optical disk having super-resolution film

A thermally-assisted magnetic recording head and a magnetic recording apparatus having the magnetic recording head built in are disclosed. The magnetic recording head is capable of recording magnetic information by heating a recording unit of a recording medium and raising its temperature to reduce magnetic coercive force and then applying recording magnetic field to the recording unit having the reduced coercive force. The magnetic recording head has a light absorbing film having an aperture, a laser device emitting and directing light through the aperture to the recording medium to head the recording unit and raise its temperature, and a recording magnetic pole for applying the recording magnetic field to the recording unit. In the aperture, an aperture width W1 is along a polarizing direction of the light emitted from the laser device while an aperture width W2 is approximately perpendicular to the polarizing direction of the aperture width W1, and the aperture width W1 is shorter than the aperture width W2. The heating source such as a laser device recedes from the medium to provide a unique configuration where a tip of the recording magnetic pole protrudes ahead of the heating source, and hence, heating beam and the recording magnetic pole can be located close to each other without losing sufficient energy density to heat the medium.

Thermally-assisted magnetic recording head, method of manufacturing the same, and thermally-assisted magnetic recording apparatus

There is provided an optical recording medium capable of preventing cross erase and increasing its recording density. The optical recording medium includes: a reflecting film; a first transparent film provided on the reflecting film; a first semitransparent film provided on the first transparent film; a second transparent film provided on the first semitransparent film; a recording film provided on the second transparent film, the recording film being capable of reversibly changing an atomic arrangement; and a third transparent film provided on the recording film. The first semitransparent film has a complex refractive index of n&#x2212;ik satisfying relationships of 0&#x3c;n&#x3c;1 and 1&#x3c;k, and a product of a thickness d (nm) of the first semitransparent film and an extinction coefficient k of the complex refractive index is d&#xd7;k&#x2266;44.

Optical recording medium

Growing community of inventors

Yokohama, Japan

Katsutaro Ichihara