Patents by Inventor Yusuke Toma

Yusuke Toma 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: 8045292
    Abstract: A perpendicular magnetic recording head is provided capable of suppressing the magnetic field attributable to the edge write phenomenon and improving resistance to an external magnetic field. The perpendicular magnetic recording head includes a magnetic layer that has a main magnetic pole on a surface facing a recording medium; a return yoke layer that is disposed on the magnetic layer with a nonmagnetic layer disposed therebetween and has a large width in the direction of the main magnetic pole; and a coil layer for applying a recording magnetic field to the magnetic layer. The return yoke layer is provided with such a shape that as seen in the plan view, the return yoke layer is exposed from the medium facing surface with a width not greater than the width in the track width direction of a protrusion region of the return yoke layer that covers the coil layer and the width of the return yoke layer gradually increases in the height direction from the medium facing surface.
    Type: Grant
    Filed: November 21, 2007
    Date of Patent: October 25, 2011
    Assignee: TDK Corporation
    Inventors: Yusuke Toma, Kiyoshi Kobayashi, Toru Takahashi, Hiroshi Kameda
  • Patent number: 8018680
    Abstract: A vertical magnetic recording head device includes: a magnetic layer that includes a main magnetic pole exposed from a surface facing a recording medium; a return yoke layer that is provided on the magnetic layer with a non-magnetic layer interposed therebetween; and coil layers that apply a recording magnetic field to the magnetic layer and the return yoke layer. In the vertical magnetic recording head device, the return yoke layer includes thick portions that extend in a height direction in edge regions arranged in a track width direction.
    Type: Grant
    Filed: November 29, 2007
    Date of Patent: September 13, 2011
    Assignee: TDK Corporation
    Inventors: Yusuke Toma, Hiroshi Kameda, Kiyoshi Kobayashi, Toru Takahashi
  • Patent number: 7983010
    Abstract: A perpendicular magnetic recording head according to the present invention is composed of a first magnetic layer having a main magnetic pole exposed at a facing surface opposite a recording medium, a second magnetic layer adjacent to the first magnetic layer with an intermediary non-magnetic layer disposed therebetween, and a coil layer for applying a recording magnetic field to the first magnetic layer. Since the second magnetic layer has a shape including a substantially arched portion in its cross section along a height direction, it becomes possible to keep an Edge Write magnetic field in a low level and improve external magnetic field resistance.
    Type: Grant
    Filed: July 20, 2007
    Date of Patent: July 19, 2011
    Assignee: TDK Corporation
    Inventors: Yusuke Toma, Hiroshi Kameda, Kiyoshi Kobayashi, Toru Takahashi, Sumihito Morita
  • Patent number: 7903371
    Abstract: A perpendicular magnetic recording head includes a first magnetic layer having a main magnetic pole exposed at a medium-facing surface that faces a recording medium; a second magnetic layer that faces the first magnetic layer with a nonmagnetic layer interposed therebetween; and a coil layer for applying a recording magnetic field to the first magnetic layer. The second magnetic layer includes a relatively thick edge portion, whereby the edge-write magnetic field is reduced and the external magnetic field resistance is increased.
    Type: Grant
    Filed: July 20, 2007
    Date of Patent: March 8, 2011
    Assignee: TDK Corporation
    Inventors: Yusuke Toma, Hiroshi Kameda, Kiyoshi Kobayashi, Toru Takahashi, Sumihito Morita, Toshinori Watanabe
  • Patent number: 7859791
    Abstract: A perpendicular magnetic recording head includes a nonmagnetic insulating layer and a main magnetic pole layer disposed on the nonmagnetic insulating layer. The main magnetic pole layer includes a pole straight part exposed in an opposing surface opposite a recording medium and a flared part that extends from the pole straight part in a height direction. The flared part broadens in a track width direction as the flared part extends in the height direction. The pole straight part of the main magnetic pole layer as viewed from the opposing surface has a trapezoidal shape over its entire length, the trapezoidal shape being narrowed at the nonmagnetic insulating layer-side. The flared part as viewed from the opposing surface has a trapezoidal shape at least at a junction with the pole straight part, the trapezoidal shape being narrowed at the nonmagnetic insulating layer-side.
    Type: Grant
    Filed: April 5, 2007
    Date of Patent: December 28, 2010
    Assignee: TDK Corporation
    Inventors: Yusuke Toma, Hiroshi Kameda, Eiji Ozaki
  • Publication number: 20080174911
    Abstract: A perpendicular magnetic recording head is provided capable of suppressing the magnetic field attributable to the edge write phenomenon and improving resistance to an external magnetic field. The perpendicular magnetic recording head includes a magnetic layer that has a main magnetic pole on a surface facing a recording medium; a return yoke layer that is disposed on the magnetic layer with a nonmagnetic layer disposed therebetween and has a large width in the direction of the main magnetic pole; and a coil layer for applying a recording magnetic field to the magnetic layer. The return yoke layer is provided with such a shape that as seen in the plan view, the return yoke layer is exposed from the medium facing surface with a width not greater than the width in the track width direction of a protrusion region of the return yoke layer that covers the coil layer and the width of the return yoke layer gradually increases as it goes toward the starting point of the height direction.
    Type: Application
    Filed: November 21, 2007
    Publication date: July 24, 2008
    Inventors: Yusuke Toma, Kiyoshi Kobayashi, Toru Takahashi, Hiroshi Kameda
  • Publication number: 20080152951
    Abstract: A vertical magnetic recording head device includes: a magnetic layer that includes a main magnetic pole exposed from a surface facing a recording medium; a return yoke layer that is provided on the magnetic layer with a non-magnetic layer interposed therebetween; and coil layers that apply a recording magnetic field to the magnetic layer and the return yoke layer.
    Type: Application
    Filed: November 29, 2007
    Publication date: June 26, 2008
    Inventors: Yusuke Toma, Hiroshi Kameda, Kiyoshi Kobayashi, Toru Takahashi
  • Publication number: 20080094730
    Abstract: A lens apparatus includes a plurality of lenses movable in a direction of the optical axis, a guide pole that extends in the direction of the optical axis and that is moved integrally with arbitrary lenses among the lenses, and a slide unit that is slidable along the guide pole and that is moved integrally with others lenses among the lenses. This makes an optical axis of the other lens moving along the guide pole to be aligned with an optical axis of the lens apparatus, by adjusting a position of the arbitrary lenses so that an optical axis of the arbitrary lenses is aligned with the optical axis of the lens apparatus.
    Type: Application
    Filed: August 28, 2007
    Publication date: April 24, 2008
    Inventor: Yusuke Toma
  • Publication number: 20080019043
    Abstract: A perpendicular magnetic recording head according to the present invention is composed of a first magnetic layer having a main magnetic pole exposed at a facing surface opposite a recording medium, a second magnetic layer adjacent to the first magnetic layer with an intermediary non-magnetic layer disposed therebetween, and a coil layer for applying a recording magnetic field to the first magnetic layer. Since the second magnetic layer has a shape including a substantially arched portion in its cross section along a height direction, it becomes possible to keep an Edge Write magnetic field in a low level and improve external magnetic field resistance.
    Type: Application
    Filed: July 20, 2007
    Publication date: January 24, 2008
    Applicant: Alps Electric Company, Ltd.
    Inventors: Yusuke TOMA, Hiroshi Kameda, Kiyoshi Kobayashi, Toru Takahashi, Sumihito Morita
  • Publication number: 20080019042
    Abstract: A perpendicular magnetic recording head includes a first magnetic layer having a main magnetic pole exposed at a medium-facing surface that faces a recording medium; a second magnetic layer that faces the first magnetic layer with a nonmagnetic layer interposed therebetween; and a coil layer for applying a recording magnetic field to the first magnetic layer. The second magnetic layer includes a relatively thick edge portion, whereby the edge-write magnetic field is reduced and the external magnetic field resistance is increased.
    Type: Application
    Filed: July 20, 2007
    Publication date: January 24, 2008
    Applicant: Alps Electric Company, Ltd.
    Inventors: Yusuke TOMA, Hiroshi Kameda, Kiyoshi Kobayashi, Toru Takahashi, Sumihito Morita, Toshinori Watanabe
  • Publication number: 20070236834
    Abstract: A perpendicular magnetic recording head includes a nonmagnetic insulating layer and a main magnetic pole layer disposed on the nonmagnetic insulating layer. The main magnetic pole layer includes a pole straight part exposed in an opposing surface opposite a recording medium and a flared part that extends from the pole straight part in a height direction. The flared part broadens in a track width direction as the flared part extends in the height direction. The pole straight part of the main magnetic pole layer as viewed from the opposing surface has a trapezoidal shape over its entire length, the trapezoidal shape being narrowed at the nonmagnetic insulating layer-side. The flared part as viewed from the opposing surface has a trapezoidal shape at least at a junction with the pole straight part, the trapezoidal shape being narrowed at the nonmagnetic insulating layer-side.
    Type: Application
    Filed: April 5, 2007
    Publication date: October 11, 2007
    Applicant: ALPS ELECTRIC CO., LTD.
    Inventors: Yusuke Toma, Hiroshi Kameda, Eiji Ozaki