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).

  • Publication number: 20100220763
    Abstract: Provided is a surface emitting laser array using a photonic crystal, which allows an active layer to be shared without disconnecting the active layer between the individual surface emitting lasers adjacent to each other, and enables high-density arraying easily. The surface emitting laser array includes: at least two surface emitting lasers formed on a substrate, each having a laminated structure of multiple semiconductor layers including a semiconductor multilayer mirror, an active layer, and a photonic crystal having a refractive index profile in an in-plane direction, the photonic crystal and the semiconductor multilayer mirror in the laminated structure forming a waveguide for guiding light in a resonance mode; and a region without the photonic crystal provided between adjacent surface emitting lasers in the surface emitting laser array, in which the surface emitting lasers have the same semiconductor multilayer mirror and the same active layer.
    Type: Application
    Filed: February 24, 2009
    Publication date: September 2, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Mitsuhiro Ikuta
  • Publication number: 20100166034
    Abstract: When configuring a surface emitting laser by a semiconductor material not capable of largely extracting a refractive-index difference, the surface emitting laser using a photonic crystal capable of forming a waveguide is provided.
    Type: Application
    Filed: October 8, 2008
    Publication date: July 1, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Mitsuhiro Ikuta
  • Patent number: 7697588
    Abstract: To provide a structure having a photonic crystal that can display a reflection function using GR even when a refractive index difference between a photonic crystal layer and a cladding layer adjacent thereto is not sufficient and a surface-emitting laser using the structure. The structure includes a photonic crystal layer including a first member of a flat shape and plural pillars arrayed two-dimensionally periodically on the first member. The photonic crystal layer is formed of a first material having a first refractive index. A low refractive index layer formed of a second material having a second refractive index lower than the first refractive index is adjacent to the photonic crystal layer. A relative refractive index difference between the first refractive index and the second refractive index is not less than 0.04 and does not exceed 0.13. The height of the pillars with respect to the thickness of the photonic crystal layer is not less than 0.10t and does not exceed 0.07t.
    Type: Grant
    Filed: November 1, 2007
    Date of Patent: April 13, 2010
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yuichiro Hori, Mitsuhiro Ikuta
  • Patent number: 7697586
    Abstract: Provided is a high-output surface-emitting laser capable of reducing effects on reflectance of an upper reflection mirror in a single transverse mode. The surface-emitting laser includes plural semiconductor layers, laminated on a substrate, which includes a lower semiconductor multilayer reflection mirror, an active layer, and an upper semiconductor multilayer reflection mirror, wherein the lower or upper semiconductor multilayer reflection mirror includes a first semiconductor layer having a two-dimensional photonic crystal structure comprised of a high and low refractive index portions which are arranged in a direction parallel to the substrate, and wherein a second semiconductor layer laminated on the first semiconductor layer includes a microhole which reaches the low refractive index portion, the cross section of the microhole in the direction parallel to the substrate being smaller than the cross section of the low refractive index portion formed in the first semiconductor layer.
    Type: Grant
    Filed: July 1, 2008
    Date of Patent: April 13, 2010
    Assignee: Canon Kabushiki Kaisha
    Inventor: Mitsuhiro Ikuta
  • Publication number: 20100080258
    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: Application
    Filed: September 18, 2009
    Publication date: April 1, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Mitsuhiro Ikuta
  • Publication number: 20100046570
    Abstract: Provided is a high-output surface-emitting laser capable of reducing effects on reflectance of an upper reflection mirror in a single transverse mode. The surface-emitting laser includes plural semiconductor layers, laminated on a substrate, which includes a lower semiconductor multilayer reflection mirror, an active layer, and an upper semiconductor multilayer reflection mirror, wherein the lower or upper semiconductor multilayer reflection mirror includes a first semiconductor layer having a two-dimensional photonic crystal structure comprised of a high and low refractive index portions which are arranged in a direction parallel to the substrate, and wherein a second semiconductor layer laminated on the first semiconductor layer includes a microhole which reaches the low refractive index portion, the cross section of the microhole in the direction parallel to the substrate being smaller than the cross section of the low refractive index portion formed in the first semiconductor layer.
    Type: Application
    Filed: October 21, 2009
    Publication date: February 25, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Mitsuhiro Ikuta
  • Publication number: 20100029030
    Abstract: Provided is a process for producing a surface emitting laser including a surface relief structure provided on laminated semiconductor layers, including the steps of transferring, to a first dielectric film, a first pattern for defining a mesa structure and a second pattern for defining the surface relief structure in the same process; and forming a second dielectric film on the first dielectric film and a surface of the laminated semiconductor layers to which the first pattern and the second pattern have been transferred. Accordingly, a center position of the surface relief structure can be aligned with a center position of a current confinement structure at high precision.
    Type: Application
    Filed: July 27, 2009
    Publication date: February 4, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Tatsuro Uchida, Mitsuhiro Ikuta, Tetsuya Takeuchi
  • Publication number: 20100029027
    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: Application
    Filed: July 27, 2009
    Publication date: February 4, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Mitsuhiro Ikuta, Yasuhisa Inao, Takako Yamaguchi
  • Publication number: 20100014548
    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: Application
    Filed: April 5, 2007
    Publication date: January 21, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Mitsuhiro Ikuta
  • Publication number: 20090262775
    Abstract: A surface emitting laser which oscillates at a wavelength X of a blue band, including a photonic crystal layer including a photonic crystal structure, an active layer provided on one surface of the photonic crystal layer, and an electrode provided on the other surface of the photonic crystal layer for injecting electric current into the active layer. The photonic crystal structure has a thickness of 100 nm or more. A laser beam is emitted toward a direction opposite to a side of the photonic crystal layer on which the electrode is provided.
    Type: Application
    Filed: April 17, 2009
    Publication date: October 22, 2009
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Takeshi Uchida, Yasuhiro Nagatomo, Yuichiro Hori, Mitsuhiro Ikuta
  • Publication number: 20090232179
    Abstract: A surface emitting laser having a photonic crystal layer 130 on a substrate 105 with an active layer therebetween, in which the photonic crystal layer includes at least a first periodic structure for resonating in an in-plane direction and a second periodic structure for modulating a light intensity distribution in an in-plane direction. The light intensity in the photonic crystal layer is periodically distributed to a region having high light intensity and a region having low light intensity by the second periodic structure. Further, a conductive film 170 for performing current injection into the active layer is selectively provided just above the region having low light intensity. The surface emitting laser provides suppression of light absorption and highly efficient current injection into an active layer to attain a high power.
    Type: Application
    Filed: April 18, 2008
    Publication date: September 17, 2009
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Mitsuhiro Ikuta
  • Patent number: 7535946
    Abstract: A structure includes a photonic crystal layer including a first member having a high refractive index in which a plurality of holes are periodically arranged, and a second member having a low refractive index. A third member is disposed on the first member. The third member has a refractive index higher than 1.0 and lower than the refractive index of the first member. The holes of the photonic crystal layer have a depth in the range of 20% to 80% of the thickness of the first member.
    Type: Grant
    Filed: November 14, 2007
    Date of Patent: May 19, 2009
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yasuhiro Nagatomo, Yuichiro Hori, Mitsuhiro Ikuta
  • Publication number: 20090086786
    Abstract: Provided is a two-dimensional surface-emitting laser array that enables to dispose more elements in a smaller area and enables compact size, high resolution, and high speed thereof. The two-dimensional surface-emitting laser array includes surface-emitting laser elements arranged in a two-dimensional manner of m rows and n columns (m is an integer of two or larger, and n is an integer of three or larger). The interval between mesas for arranging electrical wirings for individually driving the surface-emitting laser elements is assigned so that the interval in the m row direction increases according to the number of the electrical wirings passing through between the mesas.
    Type: Application
    Filed: September 19, 2008
    Publication date: April 2, 2009
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Mitsuhiro Ikuta
  • Patent number: 7499481
    Abstract: A surface-emitting laser includes reflectors. One of the reflectors has multiple layers including one or more high-refractive-index layers and one or more low-refractive-index layers which are alternately stacked. At least one of the low-refractive-index layers includes a first region containing aluminum oxide and a second region surrounding the first region. A boundary between the first and second regions is positioned within a region where laser light is emitted. The reflectance of the multilayer reflector is higher in a portion including the first region than in a portion including the second region.
    Type: Grant
    Filed: November 9, 2007
    Date of Patent: March 3, 2009
    Assignee: Canon Kabushiki Kaisha
    Inventor: Mitsuhiro Ikuta
  • Publication number: 20090035884
    Abstract: Provided is a method for manufacturing a surface-emitting laser capable of forming a photonic crystal structure inside a semiconductor highly accurately and easily without direct bonding. It is a method by laminating on a substrate a plurality of semiconductor layers including an active layer and a semiconductor layer having a photonic crystal structure formed therein, the method including the steps of forming a second semiconductor layer on a first semiconductor layer to form the photonic crystal structure, forming a plurality of microholes in the second semiconductor layer, forming a low refractive index portion in a part of the first semiconductor layer via the plurality of microholes thereby to provide the first semiconductor layer with the photonic crystal structure having a one-dimensional or two-dimensional refractive index distribution in a direction parallel to the substrate, and forming a third semiconductor layer by crystal regrowth from a surface of the second semiconductor layer.
    Type: Application
    Filed: July 2, 2008
    Publication date: February 5, 2009
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Mitsuhiro Ikuta
  • Publication number: 20090034572
    Abstract: Provided is a high-output surface-emitting laser capable of reducing effects on reflectance of an upper reflection mirror in a single transverse mode. The surface-emitting laser includes plural semiconductor layers, laminated on a substrate, which includes a lower semiconductor multilayer reflection mirror, an active layer, and an upper semiconductor multilayer reflection mirror, wherein the lower or upper semiconductor multilayer reflection mirror includes a first semiconductor layer having a two-dimensional photonic crystal structure comprised of a high and low refractive index portions which are arranged in a direction parallel to the substrate, and wherein a second semiconductor layer laminated on the first semiconductor layer includes a microhole which reaches the low refractive index portion, the cross section of the microhole in the direction parallel to the substrate being smaller than the cross section of the low refractive index portion formed in the first semiconductor layer.
    Type: Application
    Filed: July 1, 2008
    Publication date: February 5, 2009
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Mitsuhiro Ikuta
  • Publication number: 20080192779
    Abstract: A surface emitting laser comprises an underlayer, an active layer formed on the underlayer, a slab layer formed on the active layer and having a photonic crystal structure optically combined with the active layer, and a metal thin film formed on the slab layer and having a periodic fine structure; and enabling taking-out of the light beam propagating in a layer-plane direction in the slab layer through the metal thin film.
    Type: Application
    Filed: January 31, 2008
    Publication date: August 14, 2008
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Mitsuhiro Ikuta
  • Publication number: 20080117942
    Abstract: A structure includes a photonic crystal layer including a first member having a high refractive index in which a plurality of holes are periodically arranged, and a second member having a low refractive index. A third member is disposed on the first member. The third member has a refractive index higher than 1.0 and lower than the refractive index of the first member. The holes of the photonic crystal layer have a depth in the range of 20% to 80% of the thickness of the first member.
    Type: Application
    Filed: November 14, 2007
    Publication date: May 22, 2008
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Yasuhiro Nagatomo, Yuichiro Hori, Mitsuhiro Ikuta
  • Publication number: 20080112442
    Abstract: A surface-emitting laser includes reflectors. One of the reflectors has multiple layers including one or more high-refractive-index layers and one or more low-refractive-index layers which are alternately stacked. At least one of the low-refractive-index layers includes a first region containing aluminum oxide and a second region surrounding the first region. A boundary between the first and second regions is positioned within a region where laser light is emitted. The reflectance of the multilayer reflector is higher in a portion including the first region than in a portion including the second region.
    Type: Application
    Filed: November 9, 2007
    Publication date: May 15, 2008
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Mitsuhiro Ikuta
  • Publication number: 20080107145
    Abstract: To provide a structure having a photonic crystal that can display a reflection function using GR even when a refractive index difference between a photonic crystal layer and a cladding layer adjacent thereto is not sufficient and a surface-emitting laser using the structure. The structure includes a photonic crystal layer including a first member of a flat shape and plural pillars arrayed two-dimensionally periodically on the first member. The photonic crystal layer is formed of a first material having a first refractive index. A low refractive index layer formed of a second material having a second refractive index lower than the first refractive index is adjacent to the photonic crystal layer. A relative refractive index difference between the first refractive index and the second refractive index is not less than 0.04 and does not exceed 0.13. The height of the pillars with respect to the thickness of the photonic crystal layer is not less than 0.10t and does not exceed 0.07t.
    Type: Application
    Filed: November 1, 2007
    Publication date: May 8, 2008
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Yuichiro Hori, Mitsuhiro Ikuta