Patents by Inventor Eiji Komura

Eiji Komura 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: 7835102
    Abstract: Provided is a plasmon antenna in which a near-field light having a sufficient intensity is generated only in a desired location. The plasmon antenna comprises an end surface on a side where a near-field light is generated; the end surface is flat and has a shape with at least three vertexes or rounded corners; and an end surface of the plasmon antenna which is opposite to the flat end surface and receives light, is inclined with respect to the flat end surface so as to become closer to the flat end surface toward one of the at least three vertexes or rounded corners. When the light-receiving end surface of the plasmon antenna is irradiated with the light, a near-field light having a sufficient intensity can be generated at only the vertex or rounded corner toward which the entire plasmon antenna becomes thinner.
    Type: Grant
    Filed: September 26, 2008
    Date of Patent: November 16, 2010
    Assignee: TDK Corporation
    Inventors: Seiichi Takayama, Eiji Komura, Kosuke Tanaka, Daisuke Miyauchi, Koji Shimazawa
  • Patent number: 7821732
    Abstract: A thermally assisted magnetic head according to the present invention includes: a medium-facing surface, a main magnetic pole provided on the medium-facing surface, and a plasmon antenna provided on the medium-facing surface in the vicinity of the main magnetic pole, wherein the plasmon antenna is shaped as a triangular flat plate having first, second and third corners, such that the distance from the first corner to the main magnetic pole is shorter than the distance from the second corner to the main magnetic pole and the distance from the third corner to the main magnetic pole, and the interior angle ? of the first corner, the interior angle ? of the second corner and the interior angle ? of the third corner satisfy relationships ?<?, ?<? and ???.
    Type: Grant
    Filed: September 25, 2008
    Date of Patent: October 26, 2010
    Assignee: TDK Corporation
    Inventors: Eiji Komura, Seiichi Takayama, Satoshi Tomikawa, Kosuke Tanaka, Koji Shimazawa
  • Patent number: 7813086
    Abstract: Producing a thin film magnetic head includes forming a pair of openings in a predetermined region of a TMR layer formed on a lower magnetic shield layer; forming a pair of bias-applying layers in the pair of openings so that an upper surface thereof is located above an upper surface of the TMR layer; laminating a metal layer that covers the upper surface of a portion located between the pair of bias-applying layers in the TMR layer and the upper surface of the pair of bias-applying layers; forming a resist layer across the upper surface of a portion located above the pair of bias-applying layers in the metal layer and the upper surface of a portion located above the TMR layer in the metal layer; and etching a part of the TMR layer and a part of the pair of bias-applying layers with the resist layer being as a mask.
    Type: Grant
    Filed: May 21, 2007
    Date of Patent: October 12, 2010
    Assignee: TDK Corporation
    Inventors: Kosuke Tanaka, Kazuki Sato, Eiji Komura
  • Publication number: 20100238580
    Abstract: A thermally-assisted magnetic recording head is provided, in which a light source with a sufficient power is disposed in the element-integration surface to improve mass-productivity. The head comprises, in an element-integration surface of a substrate: a light source; a waveguide for propagating light from the light source; and a magnetic pole for generating write field. Further, the edge along optical axis of the light source is set to be parallel with or inclined from the edge on the opposed-to-medium surface side of the element-integration surface. In the head, since the light source is disposed in the element-integration surface, the construction of the optical system can be completed in the stage of a wafer process. This construction can be relatively facilitated and simplified; thus, mass-productivity in the head manufacturing can be improved. Further, a light source with a sufficient power (cavity length) can be disposed in the element-integration surface.
    Type: Application
    Filed: March 19, 2009
    Publication date: September 23, 2010
    Applicant: TDK Corporation
    Inventors: Koji Shimazawa, Eiji Komura
  • Publication number: 20100202256
    Abstract: A near-field light generating device includes: a base having a top surface; a waveguide that allows laser light to propagate therethrough and is disposed above the top surface of the base; and a surface plasmon generating element that is disposed above the top surface of the base so as to adjoin the waveguide in a direction parallel to the top surface of the base. The waveguide has a side surface that faces the surface plasmon generating element. The surface plasmon generating element includes: a coupling part that is opposed to a part of the side surface of the waveguide with spacing therebetween and causes excitation of a surface plasmon by coupling with evanescent light occurring from the part of the side surface; and a near-field light generating part that generates near-field light based on the surface plasmon excited at the coupling part.
    Type: Application
    Filed: February 9, 2009
    Publication date: August 12, 2010
    Applicant: TDK CORPORATION
    Inventors: Yasuhiro Ito, Seiichi Takayama, Eiji Komura, Koji Shimazawa, Satoshi Tomikawa, Shuichi Okawa
  • Publication number: 20100195238
    Abstract: A thermally assisted magnetic head includes: a slider having a medium-facing surface; and a surface-emitting semiconductor laser. The slider has: a slider substrate, on which part of the medium-facing surface is formed; and a magnetic head portion, on which another part of the medium-facing surface is formed, and which has a first surface in contact with a head stacking surface of the slider substrate and a second surface opposite the first surface. The magnetic head portion has: a main magnetic pole that generates a write magnetic field from an end face on the side of the medium-facing surface; an optical waveguide core extending along the first surface and having a light exit surface at the medium-facing surface; and a diffraction grating, which is provided in the optical waveguide core or further towards the second surface than the optical waveguide core, and the refractive index of which varies periodically along the direction in which the optical waveguide core extends.
    Type: Application
    Filed: January 30, 2009
    Publication date: August 5, 2010
    Applicant: TDK Corporation
    Inventors: Koji Shimazawa, Eiji Komura, Seiichi Takayama
  • Publication number: 20100172220
    Abstract: Provided is a near-field light generating element in which as much amount as possible of waveguide light can be coupled with a plasmon antenna. The element comprises a light waveguide and a plasmon antenna comprising a surface or edge for propagating surface plasmon excited by waveguide light, extending to a near-field light generating end. A groove is formed in a waveguide side surface. And at least a portion of the surface or edge is embedded in the groove or located directly above the groove, being opposed to a wall or bottom surface of the groove with a predetermined distance, so as for waveguide light to be coupled with the plasmon antenna in surface plasmon mode. This configuration enables the surface or edge to be located at the position in which the surface or edge can be coupled with more amount of light, thereby to improve the light use efficiency.
    Type: Application
    Filed: January 7, 2009
    Publication date: July 8, 2010
    Applicant: TDK Corporation
    Inventors: Eiji Komura, Koji Shimazawa
  • Publication number: 20100149930
    Abstract: Provided is a near-field light generating element in which reduced is the propagation loss of excited surface plasmon that propagates to the near-field light generating end. The element comprises: a waveguide through which light for exciting surface plasmon propagates; and a plasmon antenna comprising a near-field light generating end and a propagation surface or edge. The propagation surface or edge extends to the near-field light generating end, and causes surface plasmon excited by the light to propagate thereon. Further, a portion of the side surface on the near-field light generating end side is opposed to the propagation surface or edge with a predetermined distance so as for the light to be coupled with the plasmon antenna in a surface plasmon mode. In this configuration, surface plasmon can propagates without significantly changing its wavenumber, which leads to a less propagation loss, and to an improved light use efficiency.
    Type: Application
    Filed: December 16, 2008
    Publication date: June 17, 2010
    Applicant: TDK Corporation
    Inventors: Eiji Komura, Koji Shimazawa, Daisuke Miyauchi
  • Publication number: 20100103553
    Abstract: Provided is a surface plasmon antenna that can be set so that the emitting position on the end surface of the plasmon antenna where near-field light is emitted is located sufficiently close to the end of a magnetic pole. The surface plasmon antenna comprises an edge having a portion for coupling with a light in a surface plasmon mode. The edge is provided for propagating surface plasmon excited by the light and extends from the portion to a near-field light generating end surface that emits near-field light. The edge for propagating surface plasmon is a very narrow propagation region. Therefore, the near-field light generating end surface, which appears as a polished surface processed through polishing in the manufacturing of the plasmon antenna, can be made a shape with a very small size, and further can be set so that surface plasmon propagates to reach the end surface reliably.
    Type: Application
    Filed: October 29, 2008
    Publication date: April 29, 2010
    Applicant: TDK Corporation
    Inventors: Koji Shimazawa, Eiji Komura, Yasuhiro Ito, Seiichi Takayama, Satoshi Tomikawa, Daisuke Miyauchi, Kosuke Tanaka
  • Publication number: 20100079895
    Abstract: Provided is a plasmon antenna in which a near-field light having a sufficient intensity is generated only in a desired location. The plasmon antenna comprises an end surface on a side where a near-field light is generated; the end surface is flat and has a shape with at least three vertexes or rounded corners; and an end surface of the plasmon antenna which is opposite to the flat end surface and receives light, is inclined with respect to the flat end surface so as to become closer to the flat end surface toward one of the at least three vertexes or rounded corners. When the light-receiving end surface of the plasmon antenna is irradiated with the light, a near-field light having a sufficient intensity can be generated at only the vertex or rounded corner toward which the entire plasmon antenna becomes thinner.
    Type: Application
    Filed: September 26, 2008
    Publication date: April 1, 2010
    Applicant: TDK Corporation
    Inventors: Seiichi Takayama, Eiji Komura, Kosuke Tanaka, Daisuke Miyauchi, Koji Shimazawa
  • Publication number: 20100073817
    Abstract: A plasmon antenna of the present invention is used in a thermally assisted magnetic head that includes: a medium-facing surface set, parallel to an XY plane; a magnetic pole for writing, extending toward the medium-facing surface, and a plasmon antenna comprising a pair of small metal bodies irradiated with excitation light for near-field light generation propagating in a Z-axis direction. Respective corners of the small metal bodies are spaced apart opposite each other along a TE mode direction of the excitation light. A distance between the corners gives the shortest distance between the small metal bodies, and a distance from each corner to the leading end of the magnetic pole gives a shortest distance from the small metal bodies to the leading end.
    Type: Application
    Filed: September 25, 2008
    Publication date: March 25, 2010
    Applicant: TDK CORPORATION
    Inventors: Seiichi TAKAYAMA, Eiji KOMURA, Yasuhiro ITO, Kosuke TANAKA, Koji SHIMAZAWA
  • Publication number: 20100073802
    Abstract: A thermally assisted magnetic head according to the present invention includes: a medium-facing surface, a main magnetic pole provided on the medium-facing surface, and a plasmon antenna provided on the medium-facing surface in the vicinity of the main magnetic pole, wherein the plasmon antenna is shaped as a triangular flat plate having first, second and third corners, such that the distance from the first corner to the main magnetic pole is shorter than the distance from the second corner to the main magnetic pole and the distance from the third corner to the main magnetic pole, and the interior angle ? of the first corner, the interior angle ? of the second corner and the interior angle ? of the third corner satisfy relationships ?<?, ?<? and ???.
    Type: Application
    Filed: September 25, 2008
    Publication date: March 25, 2010
    Applicant: TDK CORPORATION
    Inventors: Eiji KOMURA, Seiichi TAKAYAMA, Satoshi TOMIKAWA, Kosuke TANAKA, Koji SHIMAZAWA
  • Publication number: 20100061200
    Abstract: Provided is a near-field light generating element capable of avoiding excessive temperature rise, which comprises a waveguide and a near-field light generating layer. The layer comprises: a propagation surface on which surface plasmon excited by the light propagates; and a near-field light generating end at which near-field light is generated. The end is one end of the propagation surface. And a portion of the side surface of the waveguide is opposed to a portion of the propagation surface of the near-field light generating layer with a predetermined spacing so that the light propagating through the waveguide is coupled with the near-field light generating layer in a surface plasmon mode. The near-field light generating layer is preferably tapered toward the near-field light generating end.
    Type: Application
    Filed: September 5, 2008
    Publication date: March 11, 2010
    Applicant: TDK CORPORATION
    Inventors: Koji SHIMAZAWA, Eiji KOMURA, Yasuhiro ITO, Seiichi TAKAYAMA, Satoshi TOMIKAWA, Daisuke MIYAUCHI, Kosuke TANAKA
  • Publication number: 20090266789
    Abstract: Provided is a manufacturing method of heat-assisted magnetic recording head, in which a light source unit can be easily joined to a slider with sufficiently high accuracy, under avoiding the excessive mechanical stress. The manufacturing method comprises the steps of: moving relatively the light source unit and the slider, while applying a sufficient voltage between an upper electrode of the light source and an electrode layer provided in the slider; and setting the light source unit and the slider in desired positions in a direction perpendicular to the element-integration surface of the slider substrate. The desired positions are positions where the light source just emits due to a surface contact between: the protruded portion of the lower surface of the light source; and the upper surface of the electrode layer, which is a portion of the wall surface of a step formed on the head part.
    Type: Application
    Filed: April 23, 2008
    Publication date: October 29, 2009
    Applicant: TDK CORPORATION
    Inventors: Koji SHIMAZAWA, Yasuhiro ITO, Eiji KOMURA, Seiichi TAKAYAMA, Kosuke TANAKA
  • Publication number: 20090262448
    Abstract: Provided is a heat-assisted magnetic recording head constituted of a light source unit and a slider, which can be easily joined to each other with sufficiently high accuracy of joining position. The slider comprises a head part including a waveguide having an incident center on its end. The surface including an emission center of the light source is protruded from a joining surface of the unit substrate. And a step is provided on an end surface of the head part. The protruded portion of a lower surface of the light source has a surface contact with a wall surface of the step. Further, the distance between the wall surface of the step and the incident center of the waveguide is set to be equal to the distance between the emission center of the light source and the protruded portion of the lower surface of the light source.
    Type: Application
    Filed: April 22, 2008
    Publication date: October 22, 2009
    Applicant: TDK CORPORATION
    Inventors: Koji SHIMAZAWA, Yasuhiro ITO, Eiji KOMURA, Seiichi TAKAYAMA, Kosuke TANAKA
  • Publication number: 20090201600
    Abstract: A thermally assisted magnetic head includes a main magnetic pole for writing and a near-field light generator provided near the main magnetic pole, the near-field light generator having a non-magnetic base metal layer, a non-magnetic upper metal layer, an intermediate insulating layer interposed between the base metal layer and the upper metal layer, and the base metal layer having a V-shaped groove and also the upper metal layer having a projection facing the deepest part in the groove of the base metal layer, in a vertical cross-section parallel to a medium facing surface.
    Type: Application
    Filed: January 30, 2009
    Publication date: August 13, 2009
    Applicant: TDK CORPORATION
    Inventors: Eiji KOMURA, Koji SHIMAZAWA
  • Publication number: 20090168220
    Abstract: When first and second near-field light-generating portions are irradiated with laser light or other energy rays, near-field light is generated at the tips of both the near-field light-generating portions. By means of the near-field light thus generated, a magnetic recording medium opposing the medium-opposing surface is heated, and the coercivity of the magnetic recording medium is lowered. Since at least a portion of the main magnetic pole is positioned within the spot region including the region between the first and second near-field light-generating portions, the tips of both the near-field light-generating portions and the main magnetic pole can be brought extremely close together, and high-density recording can be performed.
    Type: Application
    Filed: September 4, 2008
    Publication date: July 2, 2009
    Applicant: TDK CORPORATION
    Inventors: Eiji Komura, Koji Shimazawa, Kosuke Tanaka, Seiichi Takayama, Hitoshi Hatate
  • Publication number: 20090052076
    Abstract: While an emitting position of light from an optical waveguide and a magnetic pole end part are made closer to each other, high-density writing onto a magnetic recording medium is realized. A thermally assisted magnetic head comprises a main magnetic pole layer having a magnetic pole end part exposed at a medium-opposing surface opposing a magnetic disk, and an optical waveguide for deflecting laser light incident thereon into a laminating direction. The main magnetic pole layer is positioned on a side where the light is deflected by the optical waveguide. The magnetic pole end part projects to the side where the light is deflected by the optical waveguide. The optical waveguide projects more than the magnetic pole end part on the medium-opposing surface side.
    Type: Application
    Filed: July 18, 2008
    Publication date: February 26, 2009
    Applicant: TDK CORPORATION
    Inventors: Koji SHIMAZAWA, Hiraku HIRABAYASHI, Kosuke TANAKA, Eiji KOMURA
  • Publication number: 20080291583
    Abstract: A method of producing a thin film magnetic head includes the steps of: forming a pair of openings in a predetermined region of a TMR layer formed on a lower magnetic shield layer; forming a pair of bias-applying layers in the pair of Openings so that an upper surface thereof may be located above an upper surface of the TMR layer; laminating a metal layer that covers the upper surface of a portion located between the pair of bias-applying layers in the TMR layer and the upper surface of the pair of bias-applying layers; forming a resist layer across the upper surface of a portion located above the pair of bias-applying layers in the metal layer and the upper surface of a portion located above the TMR layer in the metal layer; and etching a part of the TMR layer and a part of the pair of bias-applying layers with the resist layer being as a mask.
    Type: Application
    Filed: May 21, 2007
    Publication date: November 27, 2008
    Applicant: TDK CORPORATION
    Inventors: Kosuke Tanaka, Kazuki Sato, Eiji Komura
  • Publication number: 20080205202
    Abstract: A thermally assisted magnetic head has a medium-facing surface facing a magnetic recording medium; a near-field light generator disposed on a light exit face in the medium-facing surface; a magnetic recording element located adjacent to the near-field light generator; and a light emitting element disposed so that emitted light thereof reaches the near-field light generator; the near-field light generator is comprised of a cusp portion and a base portion; when ?in represents a wavelength of the emitted light from the light emitting element immediately before the emitted light reaches the near-field light generator, an intensity of near-field light generated when the material forming the cusp portion is irradiated with the light of the wavelength ?in is stronger than an intensity of near-field light generated when the material forming the base portion is irradiated with the light of the wavelength ?in.
    Type: Application
    Filed: February 20, 2008
    Publication date: August 28, 2008
    Applicant: TDK CORPORATION
    Inventors: Eiji KOMURA, Koji SHIMAZAWA, Kosuke TANAKA