Patents by Inventor Norikazu Ota

Norikazu Ota has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10339965
    Abstract: A thermally assisted magnetic recording head has a waveguide that propagates laser light as propagating light; a main pole that has a first end portion on an air bearing surface (ABS) facing a magnetic recording medium and that emits a magnetic flux to the magnetic recording medium; a metal layer that is positioned between the main pole and the waveguide, that extends from a second end portion positioned on the ABS in a height direction, that generates surface plasmons from the propagating light, and that generates near-field light (NF light) from the surface plasmons at the second end portion; and a dielectric body layer that is surrounded by the metal layer and that extends from a third end portion positioned on the ABS in a height direction.
    Type: Grant
    Filed: January 26, 2017
    Date of Patent: July 2, 2019
    Assignee: TDK Corporation
    Inventors: Yuki Nishimura, Norikazu Ota
  • Publication number: 20180211686
    Abstract: A thermally assisted magnetic recording head has a waveguide that propagates laser light as propagating light; a main pole that has a first end portion on an air bearing surface (ABS) facing a magnetic recording medium and that emits a magnetic flux to the magnetic recording medium; a metal layer that is positioned between the main pole and the waveguide, that extends from a second end portion positioned on the ABS in a height direction, that generates surface plasmons from the propagating light, and that generates near-field light (NF light) from the surface plasmons at the second end portion; and a dielectric body layer that is surrounded by the metal layer and that extends from a third end portion positioned on the ABS in a height direction.
    Type: Application
    Filed: January 26, 2017
    Publication date: July 26, 2018
    Inventors: Yuki NISHIMURA, Norikazu OTA
  • Patent number: 9997178
    Abstract: A thermally assisted magnetic recording head includes: a main pole that has a main pole end face at an air bearing surface opposing a magnetic recording medium and emits magnetic flux from the main pole end face; a waveguide that propagates laser light as propagation light and has a first waveguide section provided with an incidence end face on which the laser light is incident, a second waveguide section provided with a waveguide end face positioned close to the main pole end face on the air bearing surface, and a third waveguide section that connects the first waveguide section to the second waveguide section; a metal layer surrounds at least a portion of the first waveguide section, the entire circumference of the second waveguide section and at least a portion of the third waveguide section.
    Type: Grant
    Filed: January 27, 2017
    Date of Patent: June 12, 2018
    Assignee: TDK Corporation
    Inventors: Yuki Nishimura, Norikazu Ota
  • Publication number: 20160019922
    Abstract: While a plurality of drive currents for flying height setting with current values smaller than a tentative optimum drive current are supplied to a light source, respectively, heater power is supplied to a heater part, and touch down of a thermally-assisted magnetic recording head is detected. Tentative optimum heater power is determined based on a correlation between the heater power when the touch down is detected and each drive current for flying height setting. The tentative optimum drive current is supplied to the light source part; the tentative optimum heater power is supplied to the heater part; a reference signal is recorded in a magnetic recording medium; and flying height of the thermally-assisted magnetic recording head is set by determining whether or not the reference signal is recorded with the desired signal intensity.
    Type: Application
    Filed: July 21, 2014
    Publication date: January 21, 2016
    Inventors: Norikazu OTA, Osamu NAKADA, Mitsuo OTSUKI, Shinji HARA, Daisuke MIYAUCHI, Tetsuya ROPPONGI, Koji SHIMAZAWA
  • Patent number: 9230586
    Abstract: While a plurality of drive currents for flying height setting with current values smaller than a tentative optimum drive current are supplied to a light source, respectively, heater power is supplied to a heater part, and touch down of a thermally-assisted magnetic recording head is detected. Tentative optimum heater power is determined based on a correlation between the heater power when the touch down is detected and each drive current for flying height setting. The tentative optimum drive current is supplied to the light source part; the tentative optimum heater power is supplied to the heater part; a reference signal is recorded in a magnetic recording medium; and flying height of the thermally-assisted magnetic recording head is set by determining whether or not the reference signal is recorded with the desired signal intensity.
    Type: Grant
    Filed: July 21, 2014
    Date of Patent: January 5, 2016
    Assignee: TDK Corporation
    Inventors: Norikazu Ota, Osamu Nakada, Mitsuo Otsuki, Shinji Hara, Daisuke Miyauchi, Tetsuya Roppongi, Koji Shimazawa
  • Patent number: 9165582
    Abstract: A thermal assisted magnetic recording head has a magnetic head slider having an air bearing surface that is opposite to a magnetic recording medium, a core that can propagate laser light as propagating light, a plasmon generator that includes a generator front end surface facing the air bearing surface, and a main pole facing the air bearing surface, and a laser light generator that supplies the laser light to the core. The plasmon generator generates near-field light (NF light) at the generator front end surface to heat the magnetic recording medium. The main pole includes a main pole end surface that faces the air bearing surface and that is positioned in the vicinity of the generator front end surface, and emits a magnetic flux to the magnetic recording medium from the main pole end surface.
    Type: Grant
    Filed: April 11, 2014
    Date of Patent: October 20, 2015
    Assignee: TDK Corporation
    Inventors: Shinji Hara, Eiji Komura, Norikazu Ota, Daisuke Miyauchi, Tetsuya Roppongi, Koji Shimazawa
  • Publication number: 20150294678
    Abstract: A thermal assisted magnetic recording head has a magnetic head slider having an air bearing surface that is opposite to a magnetic recording medium, a core that can propagate laser light as propagating light, a plasmon generator that includes a generator front end surface facing the air bearing surface, and a main pole facing the air bearing surface, and a laser light generator that supplies the laser light to the core. The plasmon generator generates near-field light (NF light) at the generator front end surface to heat the magnetic recording medium. The main pole includes a main pole end surface that faces the air bearing surface and that is positioned in the vicinity of the generator front end surface, and emits a magnetic flux to the magnetic recording medium from the main pole end surface.
    Type: Application
    Filed: April 11, 2014
    Publication date: October 15, 2015
    Applicant: TDK Corporation
    Inventors: Shinji HARA, Eiji KOMURA, Norikazu OTA, Daisuke MIYAUCHI, Tetsuya ROPPONGI, Koji SHIMAZAWA
  • Patent number: 9153267
    Abstract: A thermally-assisted magnetic recording head of the invention includes: a waveguide; a plasmon generator; and a light-absorbing protrusion layer provided on a leading side of the plasmon generator. A ratio W1/W2 is within a range from 2/3 to 55/3, where W1 is a width of the light-absorbing protrusion layer in an air-bearing surface, and W2 is a width of the waveguide in the air-bearing surface.
    Type: Grant
    Filed: May 13, 2014
    Date of Patent: October 6, 2015
    Assignee: TDK CORPORATION
    Inventors: Eiji Komura, Shinji Hara, Norikazu Ota, Tetsuya Roppongi, Kosuke Tanaka
  • Patent number: 8908328
    Abstract: A perpendicular magnetic write head includes: a magnetic pole having an end surface exposed on an air bearing surface, and extending in a height direction perpendicular to the air bearing surface; a first yoke having an end surface exposed on the air bearing surface, and facing a forward section of the magnetic pole with a gap layer in between; a second yoke located behind the first yoke with an insulating layer in between in the height direction, and connected to a backward section of the magnetic pole; a shield connecting the first yoke to the second yoke; and an additional magnetic layer located behind a boundary between the first yoke and the insulating layer, and in contact with the first yoke.
    Type: Grant
    Filed: October 4, 2012
    Date of Patent: December 9, 2014
    Assignee: TDK Corporation
    Inventors: Masahiro Saito, Norikazu Ota, Hiromichi Umehara, Masachika Hashino
  • Patent number: 8867168
    Abstract: A magnetic head includes a main pole, a write shield, and a return path section. The write shield includes first and second shield portions located on opposite sides of the main pole in the track width direction. The return path section includes first and second yoke portions located on opposite sides of the main pole in the track width direction. The first yoke portion is connected to the first shield portion. The second yoke portion is connected to the second shield portion. A coil surrounds at least part of the entire outer periphery of the main pole when viewed from a medium facing surface.
    Type: Grant
    Filed: December 7, 2012
    Date of Patent: October 21, 2014
    Assignee: TDK Corporation
    Inventors: Norikazu Ota, Masahiro Saito, Taro Oike, Takeo Kagami, Yosuke Antoku, Kenkichi Anagawa, Kenta Hara, Tetsuro Sasaki, Shingo Miyata, Katsuki Kurihara
  • Publication number: 20140160597
    Abstract: A magnetic head includes a main pole, a write shield, and a return path section. The write shield includes first and second shield portions located on opposite sides of the main pole in the track width direction. The return path section includes first and second yoke portions located on opposite sides of the main pole in the track width direction. The first yoke portion is connected to the first shield portion. The second yoke portion is connected to the second shield portion. A coil surrounds at least part of the entire outer periphery of the main pole when viewed from a medium facing surface.
    Type: Application
    Filed: December 7, 2012
    Publication date: June 12, 2014
    Applicant: TDK CORPORATION
    Inventors: Norikazu OTA, Masahiro SAITO, Taro OIKE, Takeo KAGAMI, Yosuke ANTOKU, Kenkichi ANAGAWA, Kenta HARA, Tetsuro SASAKI, Shingo MIYATA, Katsuki KURIHARA
  • Publication number: 20140098441
    Abstract: A perpendicular magnetic write head includes: a magnetic pole having an end surface exposed on an air bearing surface, and extending in a height direction perpendicular to the air bearing surface; a first yoke having an end surface exposed on the air bearing surface, and facing a forward section of the magnetic pole with a gap layer in between; a second yoke located behind the first yoke with an insulating layer in between in the height direction, and connected to a backward section of the magnetic pole; a shield connecting the first yoke to the second yoke; and an additional magnetic layer located behind a boundary between the first yoke and the insulating layer, and in contact with the first yoke.
    Type: Application
    Filed: October 4, 2012
    Publication date: April 10, 2014
    Applicant: TDK CORPORATION
    Inventors: Masahiro SAITO, Norikazu OTA, Hiromichi UMEHARA, Masachika HASHINO
  • Patent number: 8619389
    Abstract: A write shield includes first and second shield portions located on opposite sides of a main pole in a track width direction. A return path section includes first and second yoke portions located on opposite sides of the main pole in the track width direction. A coil surrounds at least part of the entire outer periphery of the main pole when viewed from a medium facing surface. The coil includes a first magnetic portion located in a first space between the main pole and the first yoke portion, and a second magnetic portion located in a second space between the main pole and the second yoke portion. The first and second magnetic portions are made of a magnetic conductive material.
    Type: Grant
    Filed: February 26, 2013
    Date of Patent: December 31, 2013
    Assignee: TDK Corporation
    Inventors: Masahiro Saito, Norikazu Ota, Masaya Kato, Atsushi Matsuo
  • Patent number: 8559123
    Abstract: This magnetic recording device is provided with a magnetic write head having a magnetic pole, and a magnetic recording medium having a plurality of data recording blocks. Each of the data recording blocks is formed with a plurality of write tracks, and separated, in a write track width direction, from neighboring one of the data recording blocks with a writing exudation suppression section in between. With this configuration, a magnetic mutual interference of the adjacent data recording blocks at the time of a data rewriting process is avoided even when a mutual interval of the data recording blocks is narrowed, and a good recording state is maintained in each of the data recording blocks. Therefore, it is possible to achieve an improvement in a recording density, while realizing the good and brief data rewriting process for each of the data recording blocks.
    Type: Grant
    Filed: June 14, 2010
    Date of Patent: October 15, 2013
    Assignee: TDK Corporation
    Inventors: Kei Hirata, Norikazu Ota, Noboru Yamanaka
  • Patent number: 8305709
    Abstract: A perpendicular magnetic head for writing information on a magnetic recording medium comprises an ABS, a coil for generating a magnetic flux, a magnetic pole layer, a magnetic shield layer, and a gap layer disposed between the magnetic pole layer and the magnetic shield layer. Further the magnetic head has a non-magnetic region of a non-magnetic material. The non-magnetic region is disposed in the magnetic shield layer and positioned behind the ABS at a predetermined distance. The non-magnetic region is also disposed in the magnetic shield layer and has a predetermined width. With such a configuration, an undesirable concentration of the magnetic flux on the ABS is prevented.
    Type: Grant
    Filed: August 8, 2008
    Date of Patent: November 6, 2012
    Assignee: TDK Corporation
    Inventors: Norikazu Ota, Tatsuhiro Nojima, Tsuyoshi Umehara
  • Patent number: 8102623
    Abstract: A thin-film magnetic head with a perpendicular magnetic recording structure includes a main pole layer, a nonmagnetic gap layer, and an auxiliary pole layer facing the main pole layer via the nonmagnetic gap layer. A surface of a top end section of the main pole layer has an inclined step that slopes from a lamination plane of the layers. The surface faces a top end section of the auxiliary pole layer. The top end section of the auxiliary pole layer has side shield sections at a position that is not exposed to an ABS. The side shield sections faces at least part of side surfaces in a track-width direction, of the main pole layer so as to cover at least part of the inclined step.
    Type: Grant
    Filed: August 31, 2007
    Date of Patent: January 24, 2012
    Assignee: TDK Corporation
    Inventors: Kenkichi Anagawa, Norikazu Ota
  • Publication number: 20110304939
    Abstract: This magnetic recording device is provided with a magnetic write head having a magnetic pole, and a magnetic recording medium having a plurality of data recording blocks. Each of the data recording blocks is formed with a plurality of write tracks and separated, in a write track width direction, from neighboring one of the data recording blocks with a writing exudation suppression section in between. With this configuration, a magnetic mutual interference of the adjacent data recording blocks at the time of a data rewriting process is avoided even when a mutual interval of the data recording blocks is narrowed, and a good recording state is maintained in each of the data recording blocks. Therefore, it is possible to achieve an improvement in a recording density, while realizing the good and brief data rewriting process for each of the data recording blocks.
    Type: Application
    Filed: June 14, 2010
    Publication date: December 15, 2011
    Applicant: TDK CORPORATION
    Inventors: Kei Hirata, Norikazu Ota, Noboru Yamanaka
  • Patent number: 8064163
    Abstract: Provided are a perpendicular magnetic write head capable of achieving the high performance and stability in the writing performance, and a method of manufacturing the same. On a trailing side of a main magnetic pole layer, disposed are a gap layer extending backward from an air bearing surface and an auxiliary magnetic pole layer extending backward from a position recessed from the air bearing surface. The auxiliary magnetic pole layer is partially overlapped on the gap layer. In case the auxiliary magnetic pole layer is formed using etching method in the process of manufacturing the perpendicular magnetic write head, the gap layer has a function as an etching stopper layer so that the main magnetic pole layer is protected; thereby the already-formed main magnetic pole layer is not subjected to etching.
    Type: Grant
    Filed: January 22, 2008
    Date of Patent: November 22, 2011
    Assignee: TDK Corporation
    Inventors: Norikazu Ota, Tetsuya Roppongi, Yuichi Watabe
  • Patent number: 8018675
    Abstract: The thin-film magnetic head in accordance with the present invention comprises a magnetic pole, a coil surrounding the magnetic pole, and an insulating layer covering the coil, while the insulating layer is formed from a resin containing a carbon nanotube. Preferably, the resin contains 0.05 to 5 wt % of the carbon nanotube. Preferably, the resin contains a cyclodextrin.
    Type: Grant
    Filed: March 6, 2008
    Date of Patent: September 13, 2011
    Assignee: TDK Corporation
    Inventors: Minoru Shinoda, Norikazu Ota
  • Patent number: 7983009
    Abstract: The invention provides a magnetic recording/reproducing system constructed such that until the skew angle is past the maximum skew angle ?max, the edges of the write shield layer and the edges of the lower read shield layer do not overlap on the same track, so that upon application of an external magnetic field, the already written signals are kept back from degradation.
    Type: Grant
    Filed: May 17, 2007
    Date of Patent: July 19, 2011
    Assignee: TDK Corporation
    Inventors: Norikazu Ota, Tetsuya Roppongi