Kabushiki Kaisha Toshiba

Kose Corporation

Nissan Motor Company Limited

Other

Kanto Seiki Co., Ltd.

Yoichiro Tanaka

Takashi Hikosaka

Junichi Akiyama

Tsutomu Tanaka

Akira Kikitsu

Masayuki Sagoi

Masakazu Kobayashi

Tomomi Funayama

Kazushi Tanimoto

Hiroaki Yoda

Masayuki Takagishi

Shinji Kobayashi

Tomoko Taguchi

Kazuo Suzuki

Yuji Kubota

Norio Fujiki

Norio Nakamura

Yoshiyuki Kamata

Akihiko Takeo

Tadahiko Kobayashi

Hiroyuki Tsuji

Soichi Oikawa

Katsutaro Ichihara

Makoto Asakura

Hiroki Nakamura

Keiichiro Yusu

Takeshi Okino

Yoshiaki Sonobe

Kohichi Tateyama

Futoshi Nakamura

Shigeru Takekado

Hiroshi Ohashi

Masahiro Ishikawa

Hiromi Sakata

Yasuo Ohtsubo

Kazunori Moriya

Shigeru Hoshina

Makoto Imamura

Katsuyoshi Kitagawa

Yukio Hiramoto

Kunio Sekine

Noritsugu Kawashima

Takatoshi Hayashi

Yuriko Tomita

Akihiro Enomoto

Junichiro Egawa

Takashi Nishimoto

A patterned disk medium includes a disk-shaped flat substrate including a first surface and a second surface located an opposite side of the first surface. First servo pattern areas including portions provided with magnetic members and portions provided with no magnetic members are provided on the first surface. Second servo pattern areas including portions provided with magnetic members and portions provided with no magnetic members are provided on the second surface. The magnetic members of the first and second servo pattern areas are magnetized in a direction perpendicular to the first and second surfaces. The magnetic polarity of the surfaces of the magnetic members of the second pattern areas differs from that of the surfaces of the magnetic members of the first pattern areas.

Patterned disk medium for vertical magnetic recording, and magnetic disk drive with the medium

A magnetic recording media has a magnetic layer formed on a substrate and includes data regions including a magnetic pattern constituting a recoding track and servo regions including magnetic patterns used as address bits, the data regions and the servo regions being contained in a plane of the magnetic layer. In a case where two magnetic patterns used as address bits on the servo regions corresponding to two adjacent recording tracks are arranged in such a manner that one corner of one of the magnetic patterns is closest to one corner of the other, the corners of the two magnetic patterns are substantially joined together.

Magnetic recording media, magnetic recording apparatus, and stamper

A magnetic recording/reproducing apparatus has a magnetoresistive head having a magnetoresistive film through which a current is flowed in a direction substantially perpendicular to a film plane and a pair of magnetic shields disposed to sandwich the magnetoresistive film, and a preamplifier which supplies a sense current to the magnetoresistive head in constant-current driving.

CPP magnetoresistive head including a pair of shields and a sense current preamplifier

This invention provides a perpendicular magnetic recording type disk drive comprised of a double-layered disk medium and a magnetic head containing a read head element containing a GMR element. The GMR element has a linear response dynamic range characteristic larger than an average value of a reproduction magnetic field from a disk 101 and a characteristic capable of avoiding or suppressing saturation phenomenon even if it is affected by a strong reproduction magnetic field from the disk medium.

Magnetic head including magnetoresistive element for perpendicular magnetic recording type disk drive

Disclosed is a perpendicular magnetic recording medium, comprising a nonmagnetic substrate, a longitudinal hard magnetic multi-layered film arranged on the nonmagnetic substrate, including a nonmagnetic intermediate layer and a pair of hard magnetic layers laminated one upon the other with the nonmagnetic intermediate layer interposed therebetween, and having at least two hard magnetic layers, a longitudinal soft magnetic layer formed on the longitudinal hard magnetic multi-layered film, and a perpendicular magnetic recording layer formed on the longitudinal soft magnetic layer. The perpendicular magnetic recording medium of the particular construction is capable of suppressing noise and achieves a high recording magnetic field intensity and a high recording resolution.

Perpendicular magnetic recording medium and magnetic recording-reproducing apparatus using the same

There is disclosed a disk drive having a magnetic device for applying a direct current magnetic field to the disk by using a disk with a double-layered structure in which a soft magnetic layer is provided on a lower layer of the recording magnetic layer. The magnetic device generates a direct current magnetic field to uniform a magnetic domain state of the soft magnetic layer of the disk. The intensity of the direct current is larger than the anisotropic magnetic field of the soft magnetic layer and is smaller than the coercive force of the recording magnetic layer. As a consequence, the stabilization of the magnetic domain state of the soft magnetic layer of the disk can be realized to make an attempt of decreasing the magnetic noise and establishing stabilization with respect to the disturbance magnetic field.

Device for suppressing magnetic noise of dual-layered disk in a disk drive

A magnetic recording/reproducing device comprises a recording head for magnetically recording a signal on a magnetic recording medium along a predetermined track, and a reproducing head member including a spin valve typed magnetoresistive element and bias magnetic applying means, associated with the spin valve typed magnetoresistive element, for applying a bias magnetic field to the spin valve typed magnetoresistive element, the reproducing head member for changing a sensitivity distribution in a track width direction based on a distance between the reproducing head and the recording head, and an angle difference between the direction of the reproducing head and the extending direction of the track.

Magnetic recording/reproducing device using composite head

A vehicle meter self-diagnosis apparatus includes cross coil movements,, and,, drivers,, and,, a driver control circuit,, a ROM,into which indication adjustment information of the cross coil movements,, and,is written, a CPU,, and a self-diagnosis control circuit section,being started by a reset switch,for driving the drivers,, and,and diagnosing the cross coil movements,, and

Self-diagnosis apparatus for vehicle meters and method starting a self-diagnosis mode for vehicle meters

According to this invention, there is provided a magnetic recording/reproducing system having a recording head for recording a signal in a magnetic recording medium along recording tracks having a predetermined track pitch and a reproducing head for reproducing the recorded signal. A relationship between a recording track width Tw of the recording head and a reproduction width Tr of the reproducing head is defined as Tr&gt;Tw. When conditions g&lt;(1500/Hc-Hc/4000.pi.+0.3)/(Hc/400.pi.-1/2) and g.gtoreq.(1500/Hc-Hc/4000.pi.+0.3-Tp+Tw)/(Hc/400.pi.-1/2) are satisfied, an erase region is formed between the recording tracks. In this case, the gap length of the recording head is represented by g [.mu.m], the recording track width is represented by Tw [.mu.m], the track pitch is represented by Tp [.mu.m], and the coercive force of the recording medium is represented by Hc [Oe].

Magnetic head for increasing track density of a magnetic disk

A whitening powder comprises the following ingredients:

Whitening powder

A magnetic disk drive has a magnetic head for recording or reproducing information on or from a magnetic recording medium. The magnetic recording medium includes a magnetic recording layer for information recording which has magnetic anisotropy in a direction perpendicular to a surface of the recording medium, a soft magnetic under layer under the magnetic recording layer and having soft magnetic properties, and a non-magnetic substrate. The magnetic disk drive records a signal with a skew angle on at least some tracks. A main pole has a size satisfying pL&lt;(tP-tW cos .theta.)/sin .theta., where pL is a width of an end face of the main pole in a traveling direction, tW is a track width of the end face of the main pole, tP is a track pitch, and .theta. is a skew angle of a trailing edge of the main pole.

Magnetic disk drive recording a signal with a skew angle

A magnetic recording medium comprising a substrate and a magnetic film formed on the substrate, the magnetic film including magnetic crystal grains in a non-magnetic matrix and satisfying the condition given below:

Magnetic recording medium and method for manufacturing the same

A magnetic recording and reproducing apparatus, including a probe made of a ferromagnetic film movable relative to a magnetic recording medium while having a distal end facing the magnetic recording medium; a head section having a recording element for recording a signal on the magnetic recording medium and a reproducing element including at least a probe for reproducing a signal recording on the magnetic recording medium; and a head slider for mounting the head section. The head slider includes a slider section having a slider surface facing the magnetic recording medium and configured to receive a hydrodynamic force generated by a dynamic effect of a gaseous flow caused by rotation of the magnetic recording medium, and a head support, coupled to the slider section, for supporting the head section such that the reproducing element contacts the magnetic recording medium, the head support having a mass smaller than that of the slider section, an area of a surface of the head support facing the magnetic recording medium being smaller than an area of the slider surface. The apparatus also includes a DC voltage application device for applying a DC voltage between the probe and a recording layer; and a device for detecting a tunnel current flowing between the distal end of the probe and the recording layer through a non-magnetic layer by application of the DC voltage, thereby reproducing a signal recorded on the magnetic recording medium.

Signal reproduction method and magnetic recording and reproducing

A magnetic recording apparatus comprising a perpendicular recording medium, a recording head for perpendicular magnetization the perpendicular magnetization film of the recording medium, to thereby recording signals on the recording medium, and a reproducing head of magnetoresistance type for reading signals from the recording medium. The medium comprises a substrate, an underlayer formed on the substrate, and a perpendicular magnetization film formed on the substrate and having a crystal phase of a CoPt-based alloy and a compound phase of material selected from the group consisting of Co oxide, Co nitride and Co carbide.

Perpendicular recording medium and magnetic recording apparatus

Growing community of inventors

Kawasaki, Japan

Yoichiro Tanaka