Hitachi, Ltd.

Hitachi Global Storage Technologies Netherlands B.v.

Other

Hitachi Metals, Ltd.

Hitachi Maxell, Limited

Hitachi-lg Data Storage, Inc.

Hitachi Maxwell, Ltd.

Htiachi Ltd.

Hitachi, Ltd. and Hitachi Maxell, Ltd.

Hideki Saga

Hirofumi Sukeda

Junko Ushiyama

Keikichi Andoo

Motoyasu Terao

Akemi Hirotsune

Tsuyoshi Toda

Makoto Miyamoto

Tetsuya Nishida

Yumiko Anzai

Masatoshi Ohtake

Harukazu Miyamoto

Hiroaki Nemoto

Takehiko Yorozu

Takuya Matsumoto

Seiji Yonezawa

Takeshi Maeda

Takeshi Shimano

Hisataka Sugiyama

Atsushi Saito

Yohji Maruyama

Masukazu Igarashi

Takehiko Hamaguchi

Kazuetsu Yoshida

Hiroshi Ide

Hiroyuki Awano

Masahiko Takahashi

Tetsuya Uemura

Kouichirou Wakabayashi

Kimio Nakamura

Fumiko Akagi

Osamu Komoda

Kenchi Ito

Terumi Takashi

Koichi Watanabe

Motoyasu Tsunoda

Tomohiro Okada

Tatsuya Hirai

Hiroyuki Tsuchinaga

Hiroshi Toyama

Tadao Ino

Yukie Hiratsuka

Tsuyoshi Miyai

Masaki Nagashima

Kei Ishikawa

An information recording and reproducing apparatushaving a high efficiency of information transfer includes one or more recording media forming a plurality of recording surfaces, a plurality of heads respectively disposed on the recording surfaces, a first actuator for supporting the heads and moving the heads uniformly, a plurality of second actuators provided one for an associated one of the heads, the second actuators moving the heads independently relative to the first actuator, recording processing circuits for simultaneously outputting recording signals, and reproducing processing circuits simultaneously supplied with reproduced signals read out by the heads to reproduce information from the reproduced signals.

Information recording and reproducing apparatus, information recording and reproducing system, information processing apparatus and information reproducing apparatus

A disk drive. The disk drive includes a non-volatile memory that is incapable of being overwritten more than a limited number of times, a disk and a controller. The controller includes a memory management table used to manage a correlation between a logical block address (LBA) and a physical address of the non-volatile memory. In the absence of a replaceable region in the non-volatile memory and in response to an occurrence of a failure to write data in a region, defined as a failure region, in the non-volatile memory at a first physical address correlated with a first LBA, the controller is configured to write the data at a second physical address correlated with a second LBA of the non-volatile memory different from the first LBA, and is configured to correlate in the memory management table the first LBA with the second physical address.

Disk drive and method for controlling the disk drive

Embodiments protect user data in its entirety from unauthorized access when an authorized user does not access a medium for a predetermined length of time by making encryption key data used to encrypt the user data unavailable. In one embodiment, using a magnetic disk in which a data losing time of an encryption key data recording area is shorter than a user data recording area, recording is performed to the magnetic disk while encrypting user data during recording, and encryption key data for use with encryption is recorded in the encryption data recording area. For reproduction of the user data, the encryption key data is read from the encryption key data recording area, and the user data encrypted during the recording is output while being decrypted using an encryption key generated by the encryption key data, and the encryption key data is overwritten on the encryption key data recording area.

Information recording/reproducing device and information recording medium

In an information recording/reproducing method performing a thermo-magnetic recording, a tracking offset value of a recording light spot and/or a tracking offset value of a magnetic flux detecting element is changed in accordance with a radial position at which a tracking is performed at the present time, to make a direction of a magnetic wall of a recording magnetic domain in accord with a longitudinal direction of the magnetic flux detecting element. Alternatively, a shape of a heated area is changed to be in accord with the direction of the magnetic flux detecting means at respective radial position, to make the direction of the magnetic wall of the recording magnetic domain in accord with the longitudinal direction of the magnetic flux detecting element.

Megneto-optical recording device capable of changing the shapes of heating areas

A near-field optical probe and optical near-field generator are provided. A problem of a probe having a scatterer in which optical near-field noises are generated at the parts other than for a point at which an intense optical near-field is generated, is solved. In one example of the probe, a surface of the parts except for a vertex of the scatterer at which the intense optical near-field is generated is etched so that an etching depth becomes not less than a penetration depth of the optical near-field. The probe facilitates control of noises when a sample is observed or recording marks are reproduced.

Optical head for near-field recording and reproducing device

Recording information is disclosed in which an information recording medium is irradiated with a recording energy beam that is power-modulated into at least a record power level and a record-ready power level lower than the record power level. The information is recorded on the recording medium in the form of length and interval of a mark portion. When forming a mark portion of a predetermined length, the radiation energy of the energy beam is increased as compared with when forming a mark portion of a different length before or after the first pulse of an energy beam pulse train including at least a pulse for forming the mark portion.

Information recording method and apparatus with suppressed mark edge jitters

A thermally assisted magnetic recording system is provided to achieve excellent thermal resistance and low noise. In one embodiment, a magnetic recording medium is used, in which the magnetic intergrain exchange coupling is large to let the magnetization be thermally stable by coupling the magnetic grains constituting the recording layer at room temperature (the temperature maintaining the magnetization) and reduced by heating during recording to let the recording magnetization transition slope become steep. Parameter A normalizing the slope around the coercivity of the MH-loop of the medium is 1.5&#x2266;A&#x3c;6.0 at room temperature, and it becomes approximately 1.0 with heating.

Thermally assisted recording system

The objects of the present invention are to facilitate the driving of the recording energy source, and to secure sufficient cooling time of the recording medium to promote the high-speed formation of high-precision marks and to provide high-speed and large-capacity information recording apparatuses at a low cost. To achieve the above objects, at the time of information recording, p is chosen as the integer constant for marks natural number k times long of the detection window width by referring to the mark length in the recording data sequence, the recording data sequence is discriminated according to the quotient obtained by and the remainder remaining after dividing k+p by two or more integer constants, and the energy generating means is driven according to different procedures based on the result of discrimination obtained thereby.

Information recording apparatus

Embodiments in accordance with the present invention enable a disk drive of an address system to write data normally, wherein track groups of different track widths are discretely disposed on the storage medium in a same disk drive and the dimensional relationship among physical block addresses of a sector is valid for the dimensional relationship among logical block addresses. Track groups are managed corresponding to their respective track width in a disk drive and for disposing successively in a logical block address space the respective track groups located discretely on the physical block address space.

Address assigning method, disk drive, and data writing method

Magneto-optical recording device capable of changing the shapes of heating areas

Optical near-field generator and recording apparatus using the optical near-field generator

Growing community of inventors

Kokubunji, Japan

Hideki Saga