Patents by Inventor Kimitoshi Etoh

Kimitoshi Etoh 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: 6891697
    Abstract: A magnetic head having at least a main pole having a profile on a magnetic head air bearing surface composed of a first portion having a length in a cross-track direction which continuously increases from a leading edge to a trailing edge, and a second portion located on the side of the trailing edge of the first portion. A length of the second portion in the cross-track direction at the trailing edge is substantially equal to a length in the cross-track direction at the point of contact between the first and second portions. A rate of change in the length of the second portion in the cross-track direction from the leading edge to the trailing edge is different from a rate of increase in the length of the first portion in the cross-track direction.
    Type: Grant
    Filed: October 28, 2004
    Date of Patent: May 10, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Atsushi Nakamura, Masafumi Mochizuki, Tomohiro Okada, Kimitoshi Etoh, Isao Nunokawa, Yoshiaki Kawato
  • Publication number: 20050057853
    Abstract: A magnetic head having at least a main pole having a profile on a magnetic head air bearing surface composed of a first portion having a length in a cross-track direction which continuously increases from a leading edge to a trailing edge, and a second portion located on the side of the trailing edge of the first portion. A length of the second portion in the cross-track direction at the trailing edge is substantially equal to a length in the cross-track direction at the point of contact between the first and second portions. A rate of change in the length of the second portion in the cross-track direction from the leading edge to the trailing edge is different from a rate of increase in the length of the first portion in the cross-track direction.
    Type: Application
    Filed: October 28, 2004
    Publication date: March 17, 2005
    Inventors: Atsushi Nakamura, Masafumi Mochizuki, Tomohiro Okada, Kimitoshi Etoh, Isao Nunokawa, Yoshiaki Kawato
  • Publication number: 20040240121
    Abstract: A thin-film magnetic head having little temperature rise in the element, good heat dissipation and a short magnetic path length (narrow coil pitch) and manufacturing method for same is provided. To form the coil of the thin-film magnetic head, a lower coil is first formed and after forming alumina and an inorganic compound containing alumina, a trench is formed for the upper coil by reactive ion etching. The lower coil allows uniform etching at this time and functions as a film to prevent loading effects occurring during reactive ion etching. This trench is then plated in copper and chemical mechanical planarization performed to form the upper layer coil as the dual-layer coil of the present invention. Heat from the coil is efficiently radiated towards the substrate by alumina and an inorganic compound containing alumina with good heat propagation.
    Type: Application
    Filed: August 29, 2003
    Publication date: December 2, 2004
    Inventors: Kimitoshi Etoh, Nobuo Yoshida, Moriaki Fuyama, Makoto Morijiri, Kenichi Meguro, Ichiro Oodake, Kazue Kudo, Yohji Maruyama, Katsuro Watanabe
  • Publication number: 20040228030
    Abstract: A magnetic field distribution of a recording head is made linear so that a curvature of the magnetic-transition pattern in recording bit cells can be corrected. In a SPT head having a main pole 1 and an auxiliary pole 3, a magnetic layer 32 is disposed on a trailing side of the main pole. The magnetic layer is provided with a protruding portion 32a protruding towards the main pole. A width Nw of a side of the protruding portion opposite the main pole of the protruding portion is made smaller than a width Tww of the main pole on the trailing side.
    Type: Application
    Filed: October 28, 2003
    Publication date: November 18, 2004
    Applicant: Hitachi, Ltd.
    Inventors: Masafumi Mochizuki, Atsushi Nakamura, Kimitoshi Etoh
  • Patent number: 6813116
    Abstract: A single-pole type magnetic head for perpendicular recording which reduces the amount of side writing even in the presence of a yaw angle and prevents the effective track width from decreasing, and a magnetic recording disk apparatus using the same. A main pole is composed of at least two portions where the width of the first portion continuously increases from the upstream side to the downstream side in the medium moving direction and the width of the second portion is the same as the width of the first portion's downstream edge in the medium moving direction and is constant from the upstream side to the downstream side in the medium moving direction. This prevents the recording magnetic field strength from decreasing at the track edge and increases the effective track width while suppressing side writing, thereby realizing a magnetic recording disk apparatus with a high track density.
    Type: Grant
    Filed: December 9, 2002
    Date of Patent: November 2, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Atsushi Nakamura, Masafumi Mochizuki, Tomohiro Okada, Kimitoshi Etoh, Isao Nunokawa, Yoshiaki Kawato
  • Publication number: 20040100730
    Abstract: The present invention is to provide a thin film magnetic head intended to increase precision of and to narrow a width which determines a track width of a write thin film magnetic head and to supply a stably high output substantially free from write blurring on a disk, and a method for manufacturing the same. The thin film magnetic head consisting of a magnetic circuit comprising a read head to read information, a lower magnetic film, a magnetic gap and an upper magnetic film formed with a magnetic gap between it and the lower magnetic film; and of a write head comprising a coil positioned between the upper magnetic film and the lower magnetic film and an insulating film for insulting the coil and the upper magnetic film from each other, wherein the upper magnetic film is configured of an upper first magnetic film, an upper second magnetic film and an upper third magnetic film, and the upper first magnetic film is connected to the upper third magnetic film via the upper second magnetic film.
    Type: Application
    Filed: February 26, 2003
    Publication date: May 27, 2004
    Inventors: Tetsuya Okai, Makoto Morijiri, Yoji Maruyama, Kimitoshi Etoh
  • Publication number: 20040037002
    Abstract: Disclosed herein is a magnetic head for perpendicular recording in which the main magnetic pole has reduced remanent magnetization and is less liable to cause erasure after recording. These characteristic properties were realized by constructing the magnetic head such that the recording magnetic pole and the yoke are separate from each other and the main magnetic pole is formed from a material with a high saturation magnetic flux density and the yoke is formed from a material having a negative magnetostriction constant.
    Type: Application
    Filed: January 31, 2003
    Publication date: February 26, 2004
    Applicant: Hitachi, Ltd.
    Inventors: Kazue Kudo, Yoshiaki Kawato, Kazuhiro Nakamoto, Nobuo Yoshida, Kimitoshi Etoh
  • Publication number: 20030151850
    Abstract: A single-pole type magnetic head for perpendicular recording which reduces the amount of side writing even in the presence of a yaw angle and prevents the effective track width from decreasing, and a magnetic recording disk apparatus using the same. A main pole is composed of at least two portions where the width of the first portion continuously increases from the upstream side to the downstream side in the medium moving direction and the width of the second portion is the same as the width of the first portion's downstream edge in the medium moving direction and is constant from the upstream side to the downstream side in the medium moving direction. This prevents the recording magnetic field strength from decreasing at the track edge and increases the effective track width while suppressing side writing, thereby realizing a magnetic recording disk apparatus with a high track density.
    Type: Application
    Filed: December 9, 2002
    Publication date: August 14, 2003
    Inventors: Atsushi Nakamura, Masafumi Mochizuki, Tomohiro Okada, Kimitoshi Etoh, Isao Nunokawa, Yoshiaki Kawato
  • Publication number: 20030053251
    Abstract: There is provided a thin film magnetic head, with letting a distance of a portion, where a width of a track portion in an upper magnetic pole changes, from a flying plane from a medium be Ly, and letting a distance of a portion, where a distance between right and left of a surface portion in a lower magnetic pole in a track width direction is wider than the width of the upper magnetic pole in the track width direction, from the flying plane from a medium be Tp, by creating a thin film magnetic head that is equipped with a recording head that has a relation of Tp≦Ly, it becomes possible to reduce a needless leakage magnetic field in the track width direction with securing magnetic field strength.
    Type: Application
    Filed: September 10, 2002
    Publication date: March 20, 2003
    Inventors: Nobuo Yoshida, Ichiro Oodake, Moriaki Fuyama, Kazue Kudo, Kimitoshi Etoh, Shigekazu Ohtomo, Hiroshi Fukui
  • Patent number: 6370107
    Abstract: A recording disk has a surface provided with guide grooves for controlling the position of a recording head, and recording bits formed in the guide grooves for high-density recording. The recording bits have the shape of a tadpole in a plane. The width Ws of the recording bits is greater than the width Wg of the guide grooves. An AFM probe serving as a recording head travels along the guide grooves without running off the guide grooves. When a tip part of the AFM probe coincides with the recording bit, the tip part drops deep into the guide groove, whereby the recording bit is detected.
    Type: Grant
    Filed: January 26, 1999
    Date of Patent: April 9, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Sumio Hosaka, Hajime Koyanagi, Atsushi Kikukawa, Kenchi Ito, Kimitoshi Etoh
  • Publication number: 20010040864
    Abstract: A recording disk has a surface provided with guide grooves for controlling the position of a recording head, and recording bits formed in the guide grooves for high-density recording. The recording bits have the shape of a tadpole in a plane. The width Ws of the recording bits is greater than the width Wg of the guide grooves. An AFM probe serving as a recording head travels along the guide grooves without running off the guide grooves. When a tip part of the AFM probe coincides with the recording bit, the tip part drops deep into the guide groove, whereby the recording bit is detected.
    Type: Application
    Filed: July 26, 2001
    Publication date: November 15, 2001
    Applicant: Hitachi, Ltd.
    Inventors: Sumio Hosaka, Hajime Koyanagi, Atsushi Kikukawa, Kenchi Ito, Kimitoshi Etoh
  • Patent number: 6246652
    Abstract: A recording and reproducing or observing apparatus based on a laser beam deflection detection method in which an object has a very small area for reflecting light. A laser beam emitted by a semiconductor laser diode passes through a collimator lens and a stop. The beam passes through the lens and stop and is reflected by a polarization beam splitter and focused by an objective lens onto a surface of a cantilever. Reflected light from the cantilever surface is focused by the lens before being received by a position sensor. Either the incident light or the reflected light passes through an optical path that is substantially 90 degrees relative to the optical axis of the other light.
    Type: Grant
    Filed: December 4, 1998
    Date of Patent: June 12, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Atsushi Kikukawa, Sumio Hosaka, Hajime Koyanagi, Kimitoshi Etoh