Patents by Inventor Akinari Takagi

Akinari Takagi 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: 8253653
    Abstract: An image observation system includes a pair of image observation devices each having i) an image pickup device, ii) an image pickup optical system for directing light rays from an outside world to the image pickup device, iii) a display device for displaying an outside world image obtained by the image pickup system, and iv) a display optical system for directing light from the display device to an observing eye. The optical axis of the image pickup system and the optical axis of the display system are disposed coaxially, wherein the optical axes of the image pickup systems of the pair of image observation devices define a point of intersection, and wherein a focal plane being at a position conjugate with a surface of the image pickup device with respect to the image pickup optical system is disposed at a side of the intersection point of the optical axes of the image pickup systems, which side faces an observer.
    Type: Grant
    Filed: February 6, 2007
    Date of Patent: August 28, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventor: Akinari Takagi
  • Publication number: 20110249161
    Abstract: Provided is a solid-state imaging device which can carry out ranging with high precision even when the pixel size is small. The solid-state imaging device including a pixel includes: a photoelectric conversion unit for converting light into an electrical signal; an optical waveguide provided on an light incident side of the photoelectric conversion unit, the optical waveguide being configured so that light entering from a first direction is converted into a first waveguide mode and is guided and light entering from a second direction, which is different from the first direction, is converted into a second waveguide mode and is guided; and a light blocking member provided in the optical waveguide, for reducing more light in the second waveguide mode which is guided to the photoelectric conversion unit than light in the first waveguide mode which is guided to the photoelectric conversion unit.
    Type: Application
    Filed: March 28, 2011
    Publication date: October 13, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Akinari Takagi
  • Publication number: 20110199521
    Abstract: A solid-state image sensor comprises a pixel unit having a substrate including therein a photoelectric conversion section and an optical waveguide arranged on a light incident side of the substrate so as to guide an incident light converted into a guided mode of the optical waveguide and being propagated through the optical waveguide to the photoelectric conversion section. The optical waveguide has a mode conversion section for changing a propagation state of the incident light such that the incident light being propagated through the optical waveguide has an electric field amplitude distributed with the same sign at a light incident surface of the substrate.
    Type: Application
    Filed: May 19, 2010
    Publication date: August 18, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Taro Kato, Akinari Takagi
  • Publication number: 20110156574
    Abstract: The image display apparatus includes a light transmissive substrate, and plural pixels arranged on a further inner side than the substrate. Each pixel includes a light emission layer in which phosphor particles are dispersed in a background medium having a same refractive index as that of the phosphor particle, and an excitation source exciting the phosphor particles to cause them to emit light. Each pixel further includes a refractive index distribution structure disposed between the substrate and the light emission layer and having a periodic refractive index distribution in a direction along an inner surface of the substrate.
    Type: Application
    Filed: December 16, 2010
    Publication date: June 30, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Kiyokatsu Ikemoto, Akinari Takagi
  • Publication number: 20110079867
    Abstract: A solid-state imaging device capable of making reduction in reflection at the interface between a light guide and an incident unit consistent with improvement in condensing efficiency by the light guide is provided. The solid-state imaging device includes a substrate internally including a photoelectric conversion unit, and a condensing unit provided on an optical incident side of the substrate. A configuration satisfying relationships of |N1|<|??×??| and 0.63<N1/(??/??)<1.58 on an end face of the optical incident side of the condensing unit is adopted. Here, N1 is a refractive index of a medium forming a region of the optical incident side of the condensing unit, and ? is a specific permittivity of a medium forming the condensing unit, and ? is a specific permeability of the medium forming the condensing unit.
    Type: Application
    Filed: September 29, 2010
    Publication date: April 7, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Aihiko Numata, Akinari Takagi
  • Patent number: 7751669
    Abstract: At least one exemplary embodiment is directed to a waveguide, which includes a three-dimensional photonic crystal including a first linear defect and a second linear defect. The first linear defect is disposed at part of columnar structures and is formed of a medium different from the columnar structures. The second linear defect is disposed at part of columnar structures extending in the longitudinal direction of the first linear defect and is formed of a medium having a refractive index different from that of the medium used for the columnar structures. The second linear defect is separated from the first linear defect by a distance of at least 0.5 times the out-of-plane lattice period of the three-dimensional photonic crystal in a direction in which layers including the columnar structures are stacked.
    Type: Grant
    Filed: November 10, 2006
    Date of Patent: July 6, 2010
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kiyokatsu Ikemoto, Akinari Takagi, Hikaru Hoshi, Kazuya Nobayashi, Aihiko Numata
  • Patent number: 7680382
    Abstract: At least one exemplary embodiment is directed to a method for fabricating a three-dimensional photonic crystal. In the method for fabricating the three-dimensional photonic crystal, a plurality of layers can be defined as one unit, and the total thickness of the one unit can be controlled such that an average layer-thickness of the plurality of layers in the one unit is about equal to the ideal layer-thickness so that a photonic band-gap occurs in a desired wavelength region.
    Type: Grant
    Filed: December 8, 2008
    Date of Patent: March 16, 2010
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akinari Takagi, Hikaru Hoshi, Kiyokatsu Ikemoto, Kazuya Nobayashi
  • Patent number: 7592632
    Abstract: A small-sized and high-efficiency light emitting device capable of easily emitting green light includes a resonator including a photonic crystal having a refractive-index periodic structure and a point defect member formed in the photonic crystal to disturb the refractive-index periodic structure, and an active member provided inside the resonator and formed by an In containing nitride semiconductor, wherein a wavelength determined by a band gap energy of the active member is included in a photonic band gap range of the photonic crystal, and is set to be shorter than a peak wavelength at a shortest-wavelength side of a resonance mode of the resonator in the photonic band gap range.
    Type: Grant
    Filed: September 25, 2007
    Date of Patent: September 22, 2009
    Assignee: Canon Kabushiki Kaisha
    Inventor: Akinari Takagi
  • Publication number: 20090208166
    Abstract: The three-dimensional structure includes a first waveguide (line defect) in a three-dimensional photonic crystal formed by periodically arranging first and second media, which causes light to propagate therein in a first guide mode, a second waveguide (line defect) in the three-dimensional photonic crystal, which causes light to propagate therein in a second guide mode, reflective portions provided in the first and second waveguides to reflect parts of the lights propagating in the first and second waveguides, and a first region connected to the second waveguide so as to cause at least part of the light that has propagated in the second waveguide via the reflective portion to propagate therein in a third guide mode. The reflective portions are formed of media having refractive indexes different from those the first and second waveguides. Each reflective portion has a homogeneous refractive index distribution in an entire section orthogonal to a waveguide-extending direction.
    Type: Application
    Filed: February 10, 2009
    Publication date: August 20, 2009
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Kiyokatsu Ikemoto, Akinari Takagi
  • Publication number: 20090092368
    Abstract: At least one exemplary embodiment is directed to a method for fabricating a three-dimensional photonic crystal. In the method for fabricating the three-dimensional photonic crystal, a plurality of layers can be defined as one unit, and the total thickness of the one unit can be controlled such that an average layer-thickness of the plurality of layers in the one unit is about equal to the ideal layer-thickness so that a photonic band-gap occurs in a desired wavelength region.
    Type: Application
    Filed: December 8, 2008
    Publication date: April 9, 2009
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Akinari Takagi, Hikaru Hoshi, Kiyokatsu Ikemoto, Kazuya Nobayashi
  • Patent number: 7502541
    Abstract: A resonator is provided which is produced by a defect formed in a three-dimensional photonic crystal. The three-dimensional photonic crystal can include layers containing a plurality of columnar structures with discrete structures in sublayers.
    Type: Grant
    Filed: October 14, 2005
    Date of Patent: March 10, 2009
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akinari Takagi, Hikaru Hoshi, Kiyokatsu Ikemoto
  • Publication number: 20090060410
    Abstract: Provided is a light emitting structure which can emit light having a plurality of wavelength distributions from a single light emitting structure, can be integrated at high density, and can control a radiation mode pattern of radiation light and polarization thereof. A stacked three-dimensional photonic crystal is composed of a plurality of three-dimensional photonic crystals having photonic band gaps different from one another, which are stacked. Each of the plurality of three-dimensional photonic crystals includes a resonator in which a point defect is formed.
    Type: Application
    Filed: October 31, 2008
    Publication date: March 5, 2009
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Hikaru HOSHI, Akinari TAKAGI
  • Patent number: 7462873
    Abstract: Provided is a light emitting structure which can emit light having a plurality of wavelength distributions from a single light emitting structure, can be integrated at high density, and can control a radiation mode pattern of radiation light and polarization thereof. A stacked three-dimensional photonic crystal is composed of a plurality of three-dimensional photonic crystals having photonic band gaps different from one another, which are stacked. Each of the plurality of three-dimensional photonic crystals includes a resonator in which a point defect is formed.
    Type: Grant
    Filed: April 7, 2005
    Date of Patent: December 9, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hikaru Hoshi, Akinari Takagi
  • Patent number: 7463814
    Abstract: At least one exemplary embodiment is directed to a method for fabricating a three-dimensional photonic crystal. In the method for fabricating the three-dimensional photonic crystal, a plurality of layers can be defined as one unit, and the total thickness of the one unit can be controlled such that an average layer-thickness of the plurality of layers in the one unit is about equal to the ideal layer-thickness so that a photonic band-gap occurs in a desired wavelength region.
    Type: Grant
    Filed: March 15, 2006
    Date of Patent: December 9, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akinari Takagi, Hikaru Hoshi, Kiyokatsu Ikemoto, Kazuya Nobayashi
  • Patent number: 7446943
    Abstract: A display optical system for guiding light from an original picture to an eye of an observer or a surface to have an image projected thereon is provided with a first optical system and a second optical system. The first optical system is provided with a first surface that is formed on a transparent body and has at least a reflecting action, a second surface for reflecting light reflected on the first surface toward the first surface again, and a third surface that is formed on the transparent body in the same manner as the first surface and transmits the light from the original picture. The light transmitted through the third surface travels toward the first surface and reflected for the first time on the first surface. In addition, a principal ray at central angle of view to be reflected for the last time on the first surface is reflected and travels to a side opposite to a side of the first reflection on the first surface with respect to a normal line of a surface on a hit point thereof.
    Type: Grant
    Filed: January 20, 2006
    Date of Patent: November 4, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akinari Takagi, Shoichi Yamazaki, Hideki Morishima, Kazutaka Inoguchi, Motomi Matsunaga
  • Patent number: 7414791
    Abstract: What is disclosed is an eye detection apparatus which can detect the pupil position accurately. The apparatus has an image taking unit that picks up an image of an eye and a pupil detection unit that detects the position of the pupil in the eye based on an image picked up by the image taking portion. The pupil detection unit determines the pupil position based on images picked up by the image taking unit in a plurality of states.
    Type: Grant
    Filed: October 6, 2005
    Date of Patent: August 19, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takashi Urakawa, Yoshihiroi Saito, Akinari Takagi
  • Publication number: 20080073661
    Abstract: A small-size and high-efficiency light emitting device capable of easily emitting green light includes a resonator including a photonic crystal having a refractive-index periodic structure and an isolated defect member formed in the photonic crystal to disturb the refractive-index periodic structure, and an active member provided inside the resonator and formed by an In containing nitride semiconductor, wherein a wavelength determined by a band gap energy of the active member is included in a photonic band gap range of the photonic crystal, and is set to be shorter than a peak wavelength at a shortest-wavelength side of a resonance mode which the resonator bears in the photonic band gap range.
    Type: Application
    Filed: September 25, 2007
    Publication date: March 27, 2008
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Akinari Takagi
  • Patent number: 7313307
    Abstract: At least one exemplary embodiment is directed to a waveguide including a plurality of linear defects of a three-dimensional photonic crystal, the plurality of linear defects include a first defect formed by changing the medium of some of columnar structures to a medium different from that of the columnar structures and a second linear defect formed by shifting the position or changing the shape of some of the columnar structures extending in the same direction as the first linear defect, and the first linear defect and the second linear defect are disposed apart by 0.5 times the out-of-plane lattice period or more in the stacking direction of the three-dimensional photonic crystal.
    Type: Grant
    Filed: November 10, 2006
    Date of Patent: December 25, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kiyokatsu Ikemoto, Akinari Takagi, Hikaru Hoshi, Kazuya Nobayashi, Aihiko Numata
  • Patent number: 7308181
    Abstract: At least one exemplary embodiment is directed to a method for manufacturing a three-dimensional photonic crystal including a plurality of stacked layers having periodic structures where the thickness of the periodic structures in a layer are adjusted such that the layer satisfies the following equation: neff1×H1×M=neff×H wherein H1 represents the actual thickness of the layer, neff1 represents the actual refractive index of the periodic refractive index structure, H represents the design thickness of the layer, neff represents the design effective refractive index of the periodic refractive index structure, and M represents a coefficient inclusive and between 0.5 and 2.0.
    Type: Grant
    Filed: April 13, 2006
    Date of Patent: December 11, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazuya Nobayashi, Akinari Takagi, Hikaru Hoshi, Kiyokatsu Ikemoto
  • Patent number: 7302147
    Abstract: A three-dimensional photonic crystal has periodic-refractive-index structures including a first layer having a periodic structure based on a first rectangular lattice having a period of A along a first axis and a period of B along a second axis orthogonal to the first axis in the plane direction, a second layer having a periodic structure disposed at a position shifted by +3B/8 along the second axis with respect to the position of the first rectangular lattice, a third layer having a periodic structure disposed at a position shifted by A/2 along the first axis and B/2 along the second axis with respect to the position of the periodic structure in the first layer, and a fourth layer having a periodic structure disposed at the same position as the periodic structure in the second layer.
    Type: Grant
    Filed: October 23, 2006
    Date of Patent: November 27, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akinari Takagi, Kazuya Nobayashi, Hikaru Hoshi, Kiyokatsu Ikemoto