Patents by Inventor Naoki Koyama

Naoki Koyama 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: 6839200
    Abstract: In a composite magnetic head comprising a magnetoresistive read head including a magnetic thin film having a magnetoresistive effect and soft magnetic members interposing the soft magnetic film between them through a non-magnetic insulation layer, an induction type write head including poles formed in a moving direction of a medium and a conductor crossing the poles, and disposed in the proximity of the magnetoresistive head, and a substrate supporting these heads, the present invention discloses a composite magnetic head characterized in that part of a floating surface inclusive of the magnetic head constituent members has recesses and the read/write operations to and from the medium are effected by the portion interposed by these recesses.
    Type: Grant
    Filed: October 20, 2003
    Date of Patent: January 4, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Hisashi Takano, Naoki Koyama, Hideo Tanabe, Eijin Moriwaki, Isamu Yuito, Kazuo Shiiki, Tsuyoshi Ohnishi, Tohru Ishitani, Toshio Kobayashi, Hideo Todokoro, Chiaki Ishikawa
  • Publication number: 20040090850
    Abstract: The magnetoresistance effect element is of a multilayered structure having at least magnetic layers and an intermediate layer of an insulating material, a semiconductor or an antiferromagnetic material against the magnetic layers, and the magnetoresistance effect element has terminals formed at least on the opposite magnetic layers, respectively, so that a current flows in the intermediate layer. The film surfaces of all the magnetic layers constituting the magnetoresistance effect element are opposed substantially at right angles to the recording surface of a magnetic recording medium. Therefore, the area of the magnetic layers facing the recording surface of the magnetic recording medium can be extremely reduced, and thus the magnetic field from a very narrow region of the high-density recorded magnetic recording medium can be detected by the current which has a tunneling characteristic and passes through the intermediate layer.
    Type: Application
    Filed: November 5, 2003
    Publication date: May 13, 2004
    Applicant: Hitachi, Ltd.
    Inventors: Ryoichi Nakatani, Masahiro Kitada, Naoki Koyama, Isamu Yuito, Hisashi Takano, Eijin Moriwaki, Mikio Suzuki, Masaaki Futamoto, Fumio Kugiya, Yoshibumi Matsuda, Kazuo Shiiki, Yoshinori Miyamura, Kyo Akagi, Takeshi Nakao, Hirotsugu Fukuoka, Takayuki Munemoto, Tokuho Takagaki, Toshio Kobayashi, Hideo Tanabe, Noboru Shimizu
  • Publication number: 20040080865
    Abstract: In a composite magnetic head comprising a magnetoresistive read head including a magnetic thin film having a magnetoresistive effect and soft magnetic members interposing the soft magnetic film between them through a non-magnetic insulation layer, an induction type write head including poles formed in a moving direction of a medium and a conductor crossing the poles, and disposed in the proximity of the magnetoresistive head, and a substrate supporting these heads, the present invention discloses a composite magnetic head characterized in that part of a floating surface inclusive of the magnetic head constituent members has recesses and the read/write operations to and from the medium are effected by the portion interposed by these recesses.
    Type: Application
    Filed: October 20, 2003
    Publication date: April 29, 2004
    Applicant: Hitachi, Ltd.
    Inventors: Hisashi Takano, Naoki Koyama, Hideo Tanabe, Eijin Moriwaki, Isamu Yuito, Kazuo Shiiki, Tsuyoshi Ohnishi, Tohru Ishitani, Toshio Kobayashi, Hideo Todokoro, Chiaki Ishikawa
  • Patent number: 6687099
    Abstract: The magnetoresistance effect element is of a multilayered structure having at least magnetic layers and an intermediate layer of an insulating material, a semiconductor or an antiferromagnetic material against the magnetic layers, and the magnetoresistance effect element has terminals formed at least on the opposite magnetic layers, respectively, so that a all the magnetic layers constituting the magnetoresistance effect element are opposed substantially at right angles to the recording surface of a magnetic recording medium. Therefore, the area of the magnetic layers facing the recording surface of the magnetic recording medium can be extremely reduced, and thus the magnetic field from a very narrow region of the high-density recorded magnetic recording medium can be detected by the current which has a tunneling characteristic and passes through the intermediate layer.
    Type: Grant
    Filed: October 15, 2002
    Date of Patent: February 3, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Ryoichi Nakatani, Masahiro Kitada, Naoki Koyama, Isamu Yuito, Hisashi Takano, Eijin Moriwaki, Mikio Suzuki, Masaaki Futamoto, Fumio Kugiya, Yoshibumi Matsuda, Kazuo Shiiki, Yoshinori Miyamura, Kyo Akagi, Takeshi Nakao, Hirotsugu Fukuoka, Takayuki Munemoto, Tokuho Takagaki, Toshio Kobayashi, Hideo Tanabe, Noboru Shimizu
  • Patent number: 6665141
    Abstract: In a composite magnetic head comprising a magnetoresistive read head including a magnetic thin film having a magnetoresistive effect and soft magnetic members interposing the soft magnetic film between them through a non-magnetic insulation layer, an induction type write head including poles formed in a moving direction of a medium and a conductor crossing the poles, and disposed in the proximity of the magnetoresistive head, and a substrate supporting these heads, the present invention discloses a composite magnetic head characterized in that part of a floating surface inclusive of the magnetic head constituent members has recesses and the read/write operations to and from the medium are effected by the portion interposed by these recesses.
    Type: Grant
    Filed: January 13, 2003
    Date of Patent: December 16, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Hisashi Takano, Naoki Koyama, Hideo Tanabe, Eijin Moriwaki, Isamu Yuito, Kazuo Shiiki, Tsuyoshi Ohnishi, Tohru Ishitani, Toshio Kobayashi, Hideo Todokoro, Chiaki Ishikawa
  • Publication number: 20030117750
    Abstract: The magnetoresistance effect element is of a multilayered structure having at least magnetic layers and an intermediate layer comprised of an insulating material, a semicondcutor or an antiferromagnetic material against said magnetic layers, and the magnetoresistance effect element has terminals formed with at least on the opposite magnetic layers, respectively, so that a current is sure to be flowed in the intermediate layer. The film surfaces of all the magnetic layers constituting the magnetoresistance effect element are opposed substantially at right angles to the recording surface of a magnetic recording medium. Therefore, the area of the magnetic layers facing the recording surface of the magnetic recording medium can be extremely reduced, and thus the magnetic field from a very narrow region of the high-density recorded magnetic recording medium can be detected by the current which has a tunneling characteristic and passes through the intermediate layer.
    Type: Application
    Filed: October 15, 2002
    Publication date: June 26, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Ryoichi Nakatani, Masahiro Kitada, Naoki Koyama, Isamu Yuito, Hisashi Takano, Eijin Moriwaki, Mikio Suzuki, Masaaki Futamoto, Fumio Kugiya, Yoshibumi Matsuda, Kazuo Shiiki, Yoshinori Miyamura, Kyo Akagi, Takeshi Nakao, Hirotsugu Fukuoka, Takayuki Munemoto, Tokuho Takagaki, Toshio Kobayashi, Hideo Tanabe, Noboru Shimizu
  • Publication number: 20030099063
    Abstract: In a composite magnetic head comprising a magnetoresistive read head including a magnetic thin film having a magnetoresistive effect and soft magnetic members interposing the soft magnetic film between them through a non-magnetic insulation layer, an induction type write head including poles formed in a moving direction of a medium and a conductor crossing the poles, and disposed in the proximity of the magnetoresistive head, and a substrate supporting these heads, the present invention discloses a composite magnetic head characterized in that part of a floating surface inclusive of the magnetic head constituent members has recesses and the read/write operations to and from the medium are effected by the portion interposed by these recesses.
    Type: Application
    Filed: January 13, 2003
    Publication date: May 29, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Hisashi Takano, Naoki Koyama, Hideo Tanabe, Eijin Moriwaki, Isamu Yuito, Kazuo Shiiki, Tsuyoshi Ohnishi, Tohru Ishitani, Toshio Kobayashi, Hideo Todokoro, Chiaki Ishikawa
  • Patent number: 6538844
    Abstract: In a composite magnetic head comprising a magnetoresistive read head including a magnetic thin film having a magnetoresistive effect and soft magnetic members interposing the soft magnetic film between them through a non-magnetic insulation layer, an induction type write head-including poles formed in a moving direction of a medium and a conductor crossing the poles, and disposed in the proximity of the magnetoresistive head, and a substrate supporting these heads, the present invention discloses a composite magnetic head characterized in that part of a floating surface inclusive of the magnetic head constituent members has recesses and the read/write operations to and from the medium are effected by the portion interposed by these recesses.
    Type: Grant
    Filed: February 27, 2002
    Date of Patent: March 25, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Hisashi Takano, Naoki Koyama, Hideo Tanabe, Eijin Moriwaki, Isamu Yuito, Kazuo Shiiki, Tsuyoshi Ohnishi, Tohru Ishitani, Toshio Kobayashi, Hideo Todokoro, Chiaki Ishikawa
  • Patent number: 6483663
    Abstract: Disclosed is a magnetic disk apparatus including a magnetic reproducing head portion, and a magnetic recording head including an upper magnetic core having a end portion and a rear portion. As a resist for a frame which is used for forming the rear portion, a negative resist or an electron beam resist is used, whereby the frame is formed without any adverse effect of halation from a coil insulating film. That is, it is possible to manufacture a magnetic recording head in which the rear portion of an upper magnetic core is not emerged at the face opposed to a medium, and hence to obtain a magnetic disk apparatus exhibiting an areal recording density of 5 Gbit/in2 or more by mounting a magnetic recording/reproducing head including such a magnetic recording head.
    Type: Grant
    Filed: July 15, 1999
    Date of Patent: November 19, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Tomohiro Okada, Tetsuya Okai, Shinobu Sasaki, Tadayuki Iwakura, Naoki Koyama, Takashi Kawabe, Harunobu Saito, Makoto Morijiri
  • Patent number: 6483677
    Abstract: The magnetoresistance effect element is of a multilayered structure having at least magnetic layers and an intermediate layer of an insulating material, a semiconductor or an antiferromagnetic material against the magnetic layers, and the magnetoresistance effect element has terminals formed at least on the opposite magnetic layers, respectively, so that a current flows in the intermediate layer. The film surfaces of all the magnetic layers constituting the magnetoresistance effect element are opposed substantially at right angles to the recording surface of a magnetic recording medium. Therefore, the area of the magnetic layers facing the recording surface of the magnetic recording medium can be extremely reduced, and thus the magnetic field from a very narrow region of the high-density recorded magnetic recording medium can be detected by the current which has a tunneling characteristic and passes through the intermediate layer.
    Type: Grant
    Filed: August 20, 2001
    Date of Patent: November 19, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Ryoichi Nakatani, Masahiro Kitada, Naoki Koyama, Isamu Yuito, Hisashi Takano, Eijin Moriwaki, Mikio Suzuki, Masaaki Futamoto, Fumio Kugiya, Yoshibumi Matsuda, Kazuo Shiiki, Yoshinori Miyamura, Kyo Akagi, Takeshi Nakao, Hirotsugu Fukuoka, Takayuki Munemoto, Tokuho Takagaki, Toshio Kobayashi, Hideo Tanabe, Noboru Shimizu
  • Publication number: 20020080521
    Abstract: In a composite magnetic head comprising a magnetoresistive read head including a magnetic thin film having a magnetoresistive effect and soft magnetic members interposing the soft magnetic film between them through a non-magnetic insulation layer, an induction type write head including poles formed in a moving direction of a medium and a conductor crossing the poles, and disposed in the proximity of the magnetoresistive head, and a substrate supporting these heads, the present invention discloses a composite magnetic head characterized in that part of a floating surface inclusive of the magnetic head constituent members has recesses and the read/write operations to and from the medium are effected by the portion interposed by these recesses.
    Type: Application
    Filed: February 27, 2002
    Publication date: June 27, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Hisashi Takano, Naoki Koyama, Hideo Tanabe, Eijin Moriwaki, Isamu Yuito, Kazuo Shiiki, Tsuyoshi Ohnishi, Tohru Ishitani, Toshio Kobayashi, Hideo Todokoro, Chiaki Ishikawa
  • Publication number: 20020071210
    Abstract: A thin film magnetic head has a magnetic gap and two magnetic films that hold the magnetic gap therebetween to form a magnetic circuit. At least one of the two magnetic films has a first portion the surface of which is located remote from a throat height=0 point, and exposed to a recording medium and which determines a recording track width, and a second portion not exposed to the recording medium. The cross-sectional area of magnetic path in the second portion is larger than that in the first portion.
    Type: Application
    Filed: January 22, 2002
    Publication date: June 13, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Takashi Kawabe, Shinji Narishige, Tadayuki Iwakura, Naoki Koyama, Tetsuya Okai
  • Publication number: 20020060880
    Abstract: A thin film magnetic head has a magnetic gap and two magnetic films that hold the magnetic gap therebetween to form a magnetic circuit. At least one of the two magnetic films has a first portion the surface of which is located remote from a throat height=0 point, and exposed to a recording medium and which determines a recording track width, and a second portion not exposed to the recording medium. The cross-sectional area of magnetic path in the second portion is larger than that in the first portion.
    Type: Application
    Filed: January 22, 2002
    Publication date: May 23, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Takashi Kawabe, Shinji Narishige, Tadayuki Iwakura, Naoki Koyama, Tetsuya Okai
  • Publication number: 20020041463
    Abstract: Disclosed is a magnetic disk apparatus including a magnetic reproducing head portion, and a magnetic recording head including an upper magnetic core having a end portion and a rear portion. As a resist for a frame which is used for forming the rear portion, a negative resist or an electron beam resist is used, whereby the frame is formed without any adverse effect of halation from a coil insulating film. That is, it is possible to manufacture a magnetic recording head in which the rear portion of an upper magnetic core is not emerged at the face opposed to a medium, and hence to obtain a magnetic disk apparatus exhibiting an areal recording density of 5 Gbit/in2 or more by mounting a magnetic recording/reproducing head including such a magnetic recording head.
    Type: Application
    Filed: July 15, 1999
    Publication date: April 11, 2002
    Inventors: TOMOHIRO OKADA, TETSUYA OKAI, SHINOBU SASAKI, TADAYUKI IWAKURA, NAOKI KOYAMA, TAKASHI KAWABE, HARUNOBU SAITO
  • Publication number: 20020018325
    Abstract: The magnetoresistance effect element is of a multilayered structure having at least magnetic layers and an intermediate layer comprised of an insulating material, a semicondcutor or an antiferromagnetic material against said magnetic layers, and the magnetoresistance effect element has terminals formed with at least on the opposite magnetic layers, respectively, so that a current is sure to be flowed in the intermediate layer. The film surfaces of all the magnetic layers constituting the magnetoresistance effect element are opposed substantially at right angles to the recording surface of a magnetic recording medium. Therefore, the area of the magnetic layers facing the recording surface of the magnetic recording medium can be extremely reduced, and thus the magnetic field from a very narrow region of the high-density recorded magnetic recording medium can be detected by the current which has a tunneling characteristic and passes through the intermediate layer.
    Type: Application
    Filed: August 20, 2001
    Publication date: February 14, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Ryoichi Nakatani, Masahiro Kitada, Naoki Koyama, Isamu Yuito, Hisashi Takano, Eijin Moriwaki, Mikio Suzuki, Masaaki Futamoto, Fumio Kugiya, Yoshibumi Matsuda, Kazuo Shiiki, Yoshinori Miyamura, Kyo Akagi, Takeshi Nakao, Hirotsugu Fukuoka, Takayuki Munemoto, Tokuho Takagaki, Toshio Kobayashi, Hideo Tanabe, Noboru Shimizu
  • Publication number: 20020013996
    Abstract: Disclosed is a magnetic disk apparatus including a magnetic reproducing head portion, and a magnetic recording head including an upper magnetic core having a end portion and a rear portion. As a resist for a frame which is used for forming the rear portion, a negative resist or an electron beam resist is used, whereby the frame is formed without any adverse effect of halation from a coil insulating film. That is, it is possible to manufacture a magnetic recording head in which the rear portion of an upper magnetic core is not emerged at the face opposed to a medium, and hence to obtain a magnetic disk apparatus exhibiting an areal recording density of 5 Gbit/in2 or more by mounting a magnetic recording/reproducing head including such a magnetic recording head.
    Type: Application
    Filed: September 28, 2001
    Publication date: February 7, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Tomohiro Okada, Tetsuya Okai, Shinobu Sasaki, Tadayuki Iwakura, Naoki Koyama, Harunobu Saito, Makoto Morijiri
  • Patent number: 6307707
    Abstract: In a composite magnetic head comprising a magnetoresistive read head including a magnetic thin film having a magnetoresistive effect and soft magnetic members interposing the soft magnetic film between them through a non-magnetic insulation layer, an induction type write head including poles formed in a moving direction of a medium and a conductor crossing the poles, and disposed in the proximity of the magnetoresistive head, and a substrate supporting these heads, the present invention discloses a composite magnetic head characterized in that part of a floating surface inclusive of the magnetic head constituent members has recesses and the read/write operations to and from the medium are effected by the portion interposed by these recesses.
    Type: Grant
    Filed: June 22, 2000
    Date of Patent: October 23, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Hisashi Takano, Naoki Koyama, Hideo Tanabe, Eijin Moriwaki, Isamu Yuito, Kazuo Shiiki, Tsuyoshi Ohnishi, Tohru Ishitani, Toshio Kobayashi, Hideo Todokoro, Chiaki Ishikawa
  • Patent number: 6278593
    Abstract: The magnetoresistance effect element is of a multilayered structure having at least magnetic layers and an intermediate layer of an insulating material, a semicondutor or an antiferromagnetic material against the magnetic layers, and the magneto-resistance effect element has terminals formed at least on the opposite magnetic layers, respectively, so that a current flows in the intermediate layer. The film surfaces of all the magnetic layers constituting the magnetoresistance effect element are opposed substantially at right angles to the recording surface of a magnetic recording medium. Therefore, the area of the magnetic layers facing the recording surface of the magnetic recording medium can be extremely reduced, and thus the magnetic field from a very narrow region of the high-density recorded magnetic recording medium can be detected by the current which has a tunneling characteristic and passes through the intermediate layer.
    Type: Grant
    Filed: December 21, 1999
    Date of Patent: August 21, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Ryoichi Nakatani, Masahiro Kitada, Naoki Koyama, Isamu Yuito, Hisashi Takano, Eijin Moriwaki, Mikio Suzuki, Masaaki Futamoto, Fumio Kugiya, Yoshibumi Matsuda, Kazuo Shiiki, Yoshinori Miyamura, Kyo Akagi, Takeshi Nakao, Hirotsugu Fukuoka, Takayuki Munemoto, Tokuho Takagaki, Toshio Kobayashi, Hideo Tanabe, Noboru Shimizu
  • Patent number: 6278578
    Abstract: In a composite magnetic head comprising a magnetoresistive read head including a magnetic thin film having a magnetoresistive effect and soft magnetic members interposing the soft magnetic film between them through a non-magnetic insulation layer, an induction type write head including poles formed in a moving direction of a medium and a conductor crossing the poles, and disposed in the proximity of the magnetoresistive head, and a substrate supporting these heads, the present invention discloses a composite magnetic head characterized in that part of a floating surface inclusive of the magnetic head constituent members has recesses and the read/write operations to and from the medium are effected by the portion interposed by these recesses.
    Type: Grant
    Filed: June 22, 2000
    Date of Patent: August 21, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Hisashi Takano, Naoki Koyama, Hideo Tanabe, Eijin Moriwaki, Isamu Yuito, Kazuo Shiiki, Tsuyoshi Ohnishi, Tohru Ishitani, Toshio Kobayashi, Hideo Todokoro, Chiaki Ishikawa
  • Patent number: 6111723
    Abstract: In a composite magnetic head comprising a magnetoresistive read head including a magnetic thin film having a magnetoresistive effect and soft magnetic members interposing the soft magnetic film between them through a non-magnetic insulation layer, an induction type write head including poles formed in a moving direction of a medium and a conductor crossing the poles, and disposed in the proximity of the magnetoresistive head, and a substrate supporting these heads, the present invention discloses a composite magnetic head characterized in that part of a floating surface inclusive of the magnetic head constituent members has recesses and the read/write operations to and from the medium are effected by the portion interposed by these recesses.
    Type: Grant
    Filed: May 26, 1998
    Date of Patent: August 29, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Hisashi Takano, Naoki Koyama, Hideo Tanabe, Eijin Moriwaki, Isamu Yuito, Kazuo Shiiki, Tsuyoshi Ohnishi, Tohru Ishitani, Toshio Kobayashi, Hideo Todokoro, Chiaki Ishikawa