Patents by Inventor Mitsuhiro Ikuta

Mitsuhiro Ikuta 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: 8897330
    Abstract: The present invention provides a surface emitting laser that provides a sufficient optical output and is suitable as a light source intended for electrophotographic apparatuses, and a surface-emitting-laser array and an image forming apparatus each including the surface emitting laser. The surface emitting laser includes a first stepped structure on a front surface of a front mirror. In the first stepped structure, a difference L between an optical path length in a first area and an optical path length in a second area satisfies the following expression: (¼+N)?<|L|<(¾+N)? where N is an integer.
    Type: Grant
    Filed: October 5, 2011
    Date of Patent: November 25, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventor: Mitsuhiro Ikuta
  • Publication number: 20140227007
    Abstract: A surface-emitting laser that can prevent delamination at the interface of a selective oxidation layer and a spacer layer, while suppressing any rise of voltage, to improve the reliability of operation.
    Type: Application
    Filed: April 22, 2014
    Publication date: August 14, 2014
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Yasuhisa Inao, Mitsuhiro Ikuta, Tetsuya Takeuchi
  • Patent number: 8653501
    Abstract: Provided is an emitting device which is capable of improving the luminous efficiency of an emitting layer formed using a group IV semiconductor material and obtaining an emission spectrum having a narrow band, and a manufacturing method therefor. The emitting device comprises: an emitting layer having a potential confinement structure, comprising: a well region comprising a group IV semiconductor material; and a barrier region being adjacent to the well region and comprising a group IV semiconductor material which is different from the group IV semiconductor material in the well region, wherein: a continuous region from the well region over an interface between the well region and the barrier region to a part of the barrier region comprises fine crystals; and a region in the barrier region, which is other than the continuous region comprising the fine crystals, is amorphous or polycrystalline region.
    Type: Grant
    Filed: October 13, 2011
    Date of Patent: February 18, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tetsuya Takeuchi, Tatsuro Uchida, Mitsuhiro Ikuta
  • Patent number: 8625649
    Abstract: A surface emitting laser includes a stepped structure having a step between a first region and a second region, the stepped structure provided in an emission area located in an upper portion of the upper mirror. The surface emitting laser includes a light shielding member provided in a third region between the first region and the second region. The light shielding member is not provided in a portion of the first region and a portion of the second region.
    Type: Grant
    Filed: March 7, 2012
    Date of Patent: January 7, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventors: Mitsuhiro Ikuta, Aihiko Numata
  • Publication number: 20130177336
    Abstract: The present invention provides a surface emitting laser that provides a sufficient optical output and is suitable as a light source intended for electrophotographic apparatuses, and a surface-emitting-laser array and an image forming apparatus each including the surface emitting laser. The surface emitting laser includes a first stepped structure on a front surface of a front mirror. In the first stepped structure, a difference L between an optical path length in a first area and an optical path length in a second area satisfies the following expression: (¼+N)?<|L|<(¾+N)? where N is an integer.
    Type: Application
    Filed: October 5, 2011
    Publication date: July 11, 2013
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Mitsuhiro Ikuta
  • Publication number: 20130076849
    Abstract: A first stepped structure configured to apply a reflectance difference and a second stepped structure configured to change a far field light intensity distribution are provided. A region in which a level difference of the first stepped structure is formed has a predetermined relationship with a region in which a level difference of the second stepped structure is formed.
    Type: Application
    Filed: September 10, 2012
    Publication date: March 28, 2013
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Mitsuhiro Ikuta
  • Patent number: 8329524
    Abstract: A surface emitting laser includes a lower multilayer mirror, an active layer, and an upper multilayer mirror stacked onto a substrate. A first current confinement layer having a first electrically conductive region and a first insulating region is formed above or below the active layer using a first trench structure. A second current confinement layer having a second electrically conductive region and a second insulating region is formed above or below the first current confinement layer using a second trench structure. The first and second trench structures extend from a top surface of the upper multilayer mirror towards the substrate such that the second trench structure surrounds the first trench structure. When the surface emitting laser is viewed in an in-plane direction of the substrate, a boundary between the first electrically conductive region and the first insulating region is disposed inside the second electrically conductive region.
    Type: Grant
    Filed: March 7, 2012
    Date of Patent: December 11, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventor: Mitsuhiro Ikuta
  • Patent number: 8331414
    Abstract: A surface-emitting laser includes a surface relief structure provided on an upper multilayer reflector, the surface relief structure including a region of a first laminate, a region of a second laminate that has a larger optical thickness than the first laminate, and a region of a third laminate that has a larger optical thickness than the first laminate and the second laminate.
    Type: Grant
    Filed: September 7, 2010
    Date of Patent: December 11, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventor: Mitsuhiro Ikuta
  • Patent number: 8319807
    Abstract: Provided is an electrophotographic image forming apparatus using a novel array light source to replace the LED array light sources, which enables provision of a reduced image formation spot diameter on a photoreceptor as well as a reduced spot pitch. An electrophotographic image forming apparatus according to the present invention includes an electrophotographic image forming apparatus including a light source, and an electrophotographic photoreceptor to be exposed by the light source, the light source for exposing the electrophotographic photoreceptor including: a plurality of surface plasmon waveguides for forming a potential distribution on the electrophotographic photoreceptor using near-field light generated at tips thereof, the surface plasmon waveguides being arrayed: and an excitation mechanism for exciting a surface plasmon on each of the plurality of surface plasmon waveguides.
    Type: Grant
    Filed: October 21, 2010
    Date of Patent: November 27, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventor: Mitsuhiro Ikuta
  • Publication number: 20120237261
    Abstract: A surface emitting laser includes a stepped structure having a step between a first region and a second region, the stepped structure provided in an emission area located in an upper portion of the upper mirror. The surface emitting laser includes a light shielding member provided in a third region between the first region and the second region. The light shielding member is not provided in a portion of the first region and a portion of the second region.
    Type: Application
    Filed: March 7, 2012
    Publication date: September 20, 2012
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Mitsuhiro Ikuta, Aihiko Numata
  • Patent number: 8265115
    Abstract: A surface emitting laser includes a lower multilayer mirror and an upper multilayer mirror which are provided on a substrate. A first oxidizable layer is partially oxidized to form a first current confinement layer including a first conductive region and a first insulating region. A second oxidizable layer is partially oxidized to form a second current confinement layer including a second conductive region and a second insulating region, a boundary between the first conductive region and the first insulating region being disposed inside the second current confinement layer in an in-plane direction of the substrate. The first oxidizable layer and the second oxidizable layer or layers adjacent to the respective oxidizable layers are adjusted so that when both layers are oxidized under the same oxidizing conditions, the oxidation rate of the first oxidizable layer is lower than that of the second oxidizable layer.
    Type: Grant
    Filed: July 15, 2010
    Date of Patent: September 11, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventor: Mitsuhiro Ikuta
  • Patent number: 8249123
    Abstract: The present invention provides a surface emitting laser having a novel structure which eliminates necessity to provide a low refractive index medium at an interface of a photonic crystal layer on the side of a substrate. A multilayer mirror (1300), an active layer (1200), and a refractive index periodic structure layer (1020) whose refractive index changes periodically are laminated in a direction perpendicular to a substrate (1500). The refractive index periodic structure layer is structured so as to separate a light having a wavelength ? perpendicularly incident on the refractive index periodic structure into at least a transmitted light and a diffracted light. The multilayer mirror is structured so as to have a reflectance with regard to the diffracted light higher than a reflectance with regard to the transmitted light. A resonant mode is realized within a waveguide including the refractive index periodic structure layer and the multilayer mirror.
    Type: Grant
    Filed: August 10, 2010
    Date of Patent: August 21, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventor: Mitsuhiro Ikuta
  • Publication number: 20120171790
    Abstract: A surface emitting laser includes a lower multilayer mirror, an active layer, and an upper multilayer mirror stacked onto a substrate. A first current confinement layer having a first electrically conductive region and a first insulating region is formed above or below the active layer using a first trench structure. A second current confinement layer having a second electrically conductive region and a second insulating region is formed above or below the first current confinement layer using a second trench structure. The first and second trench structures extend from a top surface of the upper multilayer mirror towards the substrate such that the second trench structure surrounds the first trench structure. When the surface emitting laser is viewed in an in-plane direction of the substrate, a boundary between the first electrically conductive region and the first insulating region is disposed inside the second electrically conductive region.
    Type: Application
    Filed: March 7, 2012
    Publication date: July 5, 2012
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Mitsuhiro Ikuta
  • Publication number: 20120147918
    Abstract: A surface emitting laser includes a stepped structure including portions having different thicknesses. The optical path length from a plane defined above the stepped structure and extending parallel to a base substrate to an interface between a front mirror and the stepped structure is set to a specific value in each of the portions of the stepped structure.
    Type: Application
    Filed: December 5, 2011
    Publication date: June 14, 2012
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Mitsuhiro Ikuta
  • Patent number: 8188487
    Abstract: A surface emitting laser includes a lower multilayer mirror, an active layer, and an upper multilayer mirror stacked onto a substrate. A first current confinement layer having a first electrically conductive region and a first insulating region is formed above or below the active layer using a first trench structure. A second current confinement layer having a second electrically conductive region and a second insulating region is formed above or below the first current confinement layer using a second trench structure. The first and second trench structures extend from a top surface of the upper multilayer mirror towards the substrate such that the second trench structure surrounds the first trench structure. When the surface emitting laser is viewed in an in-plane direction of the substrate, a boundary between the first electrically conductive region and the first insulating region is disposed inside the second electrically conductive region.
    Type: Grant
    Filed: July 15, 2010
    Date of Patent: May 29, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventor: Mitsuhiro Ikuta
  • Publication number: 20120093188
    Abstract: There is provided a surface emitting laser allowing a direction of a far-field pattern (FFP) centroid to be inclined from a normal direction of a substrate providing the surface emitting laser, comprising: a substrate; a lower reflecting mirror, an active layer, an upper reflecting mirror stacked on the substrate; and a surface relief structure located in an upper portion of a light emitting surface of the upper reflecting mirror, the surface relief structure being made of a material allowing at least some beams emitted from the surface emitting laser to be transmitted therethrough, a plurality of regions having a predetermined optical thickness in a normal direction of the substrate being formed in contact with other region in an in-plane direction of the substrate, and a distribution of the optical thickness in the in-plane direction of the substrate is asymmetric to a central axis of the light emitting regions.
    Type: Application
    Filed: October 14, 2011
    Publication date: April 19, 2012
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Mitsuhiro Ikuta
  • Publication number: 20120032143
    Abstract: Provided is an emitting device which is capable of improving the luminous efficiency of an emitting layer formed using a group IV semiconductor material and obtaining an emission spectrum having a narrow band, and a manufacturing method therefor. The emitting device comprises: an emitting layer having a potential confinement structure, comprising: a well region comprising a group IV semiconductor material; and a barrier region being adjacent to the well region and comprising a group IV semiconductor material which is different from the group IV semiconductor material in the well region, wherein: a continuous region from the well region over an interface between the well region and the barrier region to a part of the barrier region comprises fine crystals; and a region in the barrier region, which is other than the continuous region comprising the fine crystals, is amorphous or polycrystalline region.
    Type: Application
    Filed: October 13, 2011
    Publication date: February 9, 2012
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Tetsuya Takeuchi, Tatsuro Uchida, Mitsuhiro Ikuta
  • Patent number: 8073032
    Abstract: Provided is a surface emitting laser or the like capable of suppressing horizontal misalignment between the surface relief structure and the current confining structure to make higher the precision of the alignment, to thereby obtain single transverse mode characteristics with stability. The surface emitting laser having a semiconductor layer laminated therein includes: a first etching region formed by etching a part of the upper mirror; and a second etching region formed by performing etching from a bottom portion of the first etching region to a semiconductor layer for forming a current confining structure, in which a depth of the second etching region is smaller than a depth of the first etching region.
    Type: Grant
    Filed: December 28, 2010
    Date of Patent: December 6, 2011
    Assignee: Canon Kabushiki Kaisha
    Inventor: Mitsuhiro Ikuta
  • Publication number: 20110293331
    Abstract: This invention provides a surface-emitting laser that can prevent delamination at the interface of a selective oxidation layer and a spacer layer, while suppressing any rise of voltage, to improve the reliability of operation.
    Type: Application
    Filed: May 19, 2011
    Publication date: December 1, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Yasuhisa Inao, Mitsuhiro Ikuta, Tetsuya Takeuchi
  • Patent number: 8068529
    Abstract: Provided is a surface emitting laser manufacturing method, etc., which reduces process damage occurring to a surface relief structure, enabling stable provision of a single transverse mode characteristic. Provided is a method including a surface relief structure for controlling a reflectance in a light emitting portion of an upper mirror, the surface relief structure including a stepped structure, includes: forming a resist pattern including a pattern for forming a mesa structure and a pattern for forming a stepped structure, on or above the upper mirror, and performing first-phase etching for etching the surface layer of the upper mirror to determine the horizontal position of the stepped structure; forming a current confining structure after the performing first-phase etching; and performing second-phase etching for further etching the area that the first-phase etching has been performed, to determine the depth position of the stepped structure, after the forming a current confining structure.
    Type: Grant
    Filed: December 2, 2010
    Date of Patent: November 29, 2011
    Assignee: Canon Kabushiki Kaisha
    Inventors: Mitsuhiro Ikuta, Yasuhisa Inao, Takako Yamaguchi