Patents by Inventor Kazuhisa Yamamoto

Kazuhisa Yamamoto 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).

  • Display device
    Publication number: 20070035826
    Abstract: A display device of the present invention is provided with a light source (4) for emitting coherent light and displaying an image, and an image receiving part (1) comprising not less than two screens, onto which the coherent light is projected, wherein at least one of the screens constituting the image receiving part (1) is vibrated by an airflow applied to a front or rear surface of the image receiving part (1). Further, the image receiving part (1) has a function of a speaker. Thereby, when coherent light is used as a light source for display, it is possible to suppress spots of light intensity which are called speckle noise and occur due to interference of laser beams reflected at the image receiving part.
    Type: Application
    Filed: September 30, 2004
    Publication date: February 15, 2007
    Inventors: Toshifumi Yokoyama, Ken'ichi Kasazumi, Kazuhisa Yamamoto
  • Optical waveguide device, optical waveguide laser using the same and optical apparatus equipped with the same
    Patent number: 7171094
    Abstract: An optical waveguide device includes a waveguide layer that converts a wavelength of incident light and emits converted light. In the waveguide layer, a ridge waveguide and slab waveguides are provided, the slab waveguides being formed on both sides of the ridge waveguide with recess portions intervening therebetween. The waveguide layer satisfies a multi-mode condition for the incident light, and light propagating through the ridge waveguide is in a single mode.
    Type: Grant
    Filed: December 22, 2003
    Date of Patent: January 30, 2007
    Assignees: Matsushita Electric Industrial Co., Ltd., NGK Insulators, Ltd.
    Inventors: Kiminori Mizuuchi, Kazuhisa Yamamoto, Minoru Imaeda, Tatsuo Kawaguchi, Takashi Yoshino
  • Optical pickup and optical information recording/reproducing device
    Patent number: 7154837
    Abstract: An optical pickup and an optical information recording/reproducing device are provided, each of which is capable of forming a super-resolution spot to conduct micro-mark recording, and does not undergo signal degradation due to an increased sidelobe in a reproducing operation. A variable phase filter having three regions to produce a phase difference in a radial direction is used, to provide a phase difference of ? between the center region and the side regions in a recording operation, so that a super-resolution spot is formed on a recording layer of the optical disk. In a reproducing operation, a phase difference is nullified between the regions of the variable phase filter, so that a normal light spot at a diffraction limit having a smaller sidelobe is formed. The variable phase filter can be formed with a homogeneous-alignment liquid crystal element.
    Type: Grant
    Filed: May 30, 2001
    Date of Patent: December 26, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Ken'ichi Kasazumi, Yasuo Kitaoka, Kiminori Mizuuchi, Kazuhisa Yamamoto
  • Illumination light source and two-dimensional image display using same
    Publication number: 20060285078
    Abstract: A 2-D beam scan method using a galvanometer mirror and a polygon scanner has a problem that the polygon scanner is large and noises are increased. Also, a method of oscillating a compact mirror has a problem that a brightness distribution is produced depending on a scan angle. Hence, a beam is scanned while a relatively small mirror, such as an MEMS mirror, is oscillated at or in the vicinity of the resonance frequency. In this instance, the scan angle is corrected with the use of a correction optical system for uniform illumination to be achieved.
    Type: Application
    Filed: February 24, 2005
    Publication date: December 21, 2006
    Inventors: Ken'ichi Kasazumi, Kiminori Mizuuchi, Kazuhisa Yamamoto
  • Optical information processing device and recording medium
    Patent number: 7139233
    Abstract: An optical information processing device is provided with a multi-wavelength light source that emits light of two or more different wavelengths, a filter portion that separates the light emitted from the multi-wavelength light source according to wavelength, and a condensing lens that focuses a plurality of lights separated by the filter portion on the same point for multi-wavelength recording.
    Type: Grant
    Filed: August 18, 2003
    Date of Patent: November 21, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kiminori Mizuuchi, Kazuhisa Yamamoto
  • Optical waveguide device, coherent light source using the same and optical apparatus having same
    Publication number: 20060257084
    Abstract: An optical waveguide device has a substrate composed of a nonlinear optical material and a periodically domain-inverted structure having the same composition as the nonlinear optical material, where the domain-inverted structure has a refractive index distribution relying on the domain-inverted structure.
    Type: Application
    Filed: December 22, 2003
    Publication date: November 16, 2006
    Inventors: Kiminori Mizuuchi, Kazuhisa Yamamoto, Minoru Imaeda, Tatsuo Kawaguchi, Takashi Yoshino
  • Ultrashort pulsed laser and optical head using the same
    Publication number: 20060251132
    Abstract: An ultrashort pulsed laser device includes: a pump laser diode having linear polarization; a solid laser medium oscillating with linear polarization; an optical fiber maintaining a polarization direction; and a saturable absorber mirror. The solid laser medium is disposed between the optical fiber and the saturable absorber mirror. Laser light emitted from the pump laser diode optically is coupled with a first end face of the optical fiber, and laser light emitted from a second end face of the optical fiber pumps the solid laser medium. The first end face of the optical fiber and the saturable absorber mirror constitute a laser resonator. With this configuration, mode lock can be realized stably at a repetition frequency of several hundred MHz.
    Type: Application
    Filed: July 11, 2006
    Publication date: November 9, 2006
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Yasuo Kitaoka, Kazuhisa Yamamoto
  • Optical apparatus and method for producing the same
    Patent number: 7133428
    Abstract: A light generating apparatus includes: a submount; a semiconductor laser chip mounted on the submount; a substrate which is mounted on the submount and includes an optical waveguide; and a substance having a predetermined thickness which is disposed between the semiconductor laser chip and the substrate. In an oscillation wavelength stabilizing apparatus for a light source, the light source is a semiconductor laser which includes: an active region for providing gain; and a distributed Bragg reflection (DBR) region for controlling an oscillation wavelength.
    Type: Grant
    Filed: June 13, 2003
    Date of Patent: November 7, 2006
    Assignee: MMatsushita Electric Industrial Co., Ltd.
    Inventors: Yasuo Kitaoka, Kazuhisa Yamamoto, Makoto Kato, Kiminori Mizuuchi, Kenichi Nishiuchi
  • Two-dimensional image forming apparatus
    Publication number: 20060227293
    Abstract: A two-dimensional image formation apparatus according to the present invention is provided with laser sources (1a)˜(1c), diffusers (6a)˜(6c) for diffusing light, illumination optical systems for irradiating the diffusers (6a)˜(6c) with lights emitted from the laser sources (1a)˜(1c), diffuser vibration units (13a)˜(13c) for vibrating the diffusers (6a)˜(6c), and spatial light modulators (7a)˜(7c) disposed near the diffusers (6a)˜(6c), for modulating the lights emitted from the laser sources (1a)˜(1c) and diffused by the diffusers (6a)˜(6c), wherein the diffusers (6a)˜(6c) are vibrated by the diffuser vibration units (13a)˜(13c) at a velocity that satisfies a relationship, V>d×30 (millimeters/sec), which is established between the grain size d of the diffusers and the vibration speed V of the diffusers, whereby speckle noise existing in an image projected on a screen (11) can be effectively reduced.
    Type: Application
    Filed: July 22, 2004
    Publication date: October 12, 2006
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Ken'ichi Kasazumi, Kiminori Mizuuchi, Kazuhisa Yamamoto
  • Coherent light source and control method thereof, and display unit and laser display using them
    Publication number: 20060209913
    Abstract: In a display device that displays a video by scanning coherent light across a screen, modulation at high speeds and gradation are necessary for a coherent light source. An oscillation wavelength of a semiconductor laser outputting the fundamental wave is changed at high speeds through the plasma effect induced by applying a pulse current to the coherent light source. A change of the wavelength causes the output of a higher harmonic generated in a light wavelength conversion element to change, and gradation is produced using such a change.
    Type: Application
    Filed: January 26, 2005
    Publication date: September 21, 2006
    Inventors: Toshifumi Yokoyama, Kazuhisa Yamamoto
  • Optical device, laser beam source, laser apparatus and method of producing optical device
    Patent number: 7101723
    Abstract: After forming domain inverted layers 3 in an LiTaO3 substrate 1, an optical waveguide is formed. By performing low-temperature annealing for the optical wavelength conversion element thus formed, a stable proton exchange layer 8 is formed, where an increase in refractive index generated during high-temperature annealing is lowered, thereby providing a stable optical wavelength conversion element. Thus, the phase-matched wavelength becomes constant, and variation in harmonic wave output is eliminated. Consequently, with respect to an optical wavelength conversion element utilizing a non-linear optical effect, a highly reliable element is provided.
    Type: Grant
    Filed: November 13, 2003
    Date of Patent: September 5, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kazuhisa Yamamoto, Kiminori Mizuuchi, Yasuo Kitaoka, Makoto Kato
  • Ultrashort pulsed laser and optical head using the same
    Patent number: 7103076
    Abstract: An ultrashort pulsed laser device includes: a pump laser diode having linear polarization; a solid laser medium oscillating with linear polarization; an optical fiber maintaining a polarization direction; and a saturable absorber mirror. The solid laser medium is disposed between the optical fiber and the saturable absorber mirror. Laser light emitted from the pump laser diode optically is coupled with a first end face of the optical fiber, and laser light emitted from a second end face of the optical fiber pumps the solid laser medium. The first end face of the optical fiber and the saturable absorber mirror constitute a laser resonator. With this configuration, mode lock can be realized stably at a repetition frequency of several hundred MHz.
    Type: Grant
    Filed: October 22, 2003
    Date of Patent: September 5, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yasuo Kitaoka, Kazuhisa Yamamoto
  • Optical multilayer disk, multiwavelength light source, and optical system using them
    Publication number: 20060193231
    Abstract: When a wavelength of a first laser beam with which a first recording medium including a first recording layer is recorded and reproduced is indicated as ?1 (nm), a wavelength of a second laser beam with which a second recording medium including a second recording layer is recorded and reproduced as ?2 (nm), the relationship between the wavelength ?1 and the wavelength ?2 is set to be expressed by 10?|?1??2|?120. The first recording layer has a light absorptance ratio of at least 1.0 with respect to the wavelength ?1. The light transmittance of the first recording medium with respect to the wavelength ?2 is set to be at least 30 in both the cases where the recording layer is in a crystal state and in an amorphous state. In order to record and reproduce the optical multilayer disk with the above-mentioned characteristics, a multiwavelength light source with the following configuration is used.
    Type: Application
    Filed: April 24, 2006
    Publication date: August 31, 2006
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kiminori Mizuuchi, Kazuhisa Yamamoto, Rie Kojima, Noboru Yamada
  • Electric oil pump control system in hybrid vehicle
    Publication number: 20060190145
    Abstract: An electric oil pump control system for a hybrid vehicle which has an engine and a first electric motor as driving sources; a hydraulic automatic transmission connected between the engine and drive wheels of the vehicle; an electric oil pump for generating an oil pressure necessary for performing gear change of the transmission. The hybrid vehicle can run by at least one of the engine and the first electric motor in accordance with a driving state of the vehicle. The control system has a control device for driving the electric oil pump so as to generate an oil pressure supplied to the hydraulic automatic transmission, wherein the control device drives the electric oil pump when the hybrid vehicle runs with the engine and the electric oil pump which are stopped, in accordance with a predetermined condition by which it is determined that the electric oil pump should be driven.
    Type: Application
    Filed: January 27, 2006
    Publication date: August 24, 2006
    Inventors: Akihiro Yamamoto, Kazuhisa Yamamoto
  • Device and method for inspecting wavelength-variable semiconductor laser, and method for inspecting coherent source
    Patent number: 7082146
    Abstract: A method for easily and quickly evaluating the wavelength variability properties of a wavelength-variable semiconductor laser is provided. An inspection device includes a power source for supplying current to a wavelength-variable DBR semiconductor laser having an active region, a phase control region, and a DBR region, a photo-detector for detecting an output intensity of laser beam emitted from the wavelength-variable DBR semiconductor laser, and a transmission type wavelength-selection element that can be inserted into a light path from the wavelength-variable DBR semiconductor laser to the photo-detector.
    Type: Grant
    Filed: August 4, 2005
    Date of Patent: July 25, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yasuo Kitaoka, Toshifumi Yokoyama, Kazuhisa Yamamoto
  • Laser projector
    Publication number: 20060158725
    Abstract: The present invention provides a reflection-type laser projector (100) which projects modulated laser beams outputted from a laser projection unit (40), on a screen, wherein a reflector (112) as a constituent of the screen (110) has reflection characteristics of reflecting, among the incident light, only laser beams of three colors of red, blue, and green, which are projected from the laser projection unit (40) and light in the neighboring wavelength band, and transmitting light in other wavelength band, thereby preventing pictures on the screen (110) from becoming hard to be seen due to effects of indoor illumination or light from outdoors.
    Type: Application
    Filed: June 4, 2004
    Publication date: July 20, 2006
    Inventors: Kazuhisa Yamamoto, Kiminori Mizuuchi, Yasuo Kitaoka, Ken'ichi Kasazumi
  • Optical multilayer disk, multiwavelength light source, and optical system using them
    Patent number: 7065035
    Abstract: When a wavelength of a first laser beam with which a first recording medium including a first recording layer is recorded and reproduced is indicated as ?1 (nm), a wavelength of a second laser beam with which a second recording medium including a second recording layer is recorded and reproduced as ?2 (nm), the relationship between the wavelength ?1 and the wavelength ?2 is set to be expressed by 10?|?1??2|?120. The first recording layer has a light absorptance ratio of at least 1.0 with respect to the wavelength ?1. The light transmittance of the first recording medium with respect to the wavelength ?2 is set to be at least 30 in both the cases where the recording layer is in a crystal state and in an amorphous state. In order to record and reproduce the optical multilayer disk with the above-mentioned characteristics, a multiwavelength light source with the following configuration is used.
    Type: Grant
    Filed: October 23, 2000
    Date of Patent: June 20, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kiminori Mizuuchi, Kazuhisa Yamamoto, Rie Kojima, Noboru Yamada
  • Optical waveguide device, optical waveguide laser using the same and optical apparatus having same
    Publication number: 20060109542
    Abstract: An optical waveguide device includes a waveguide layer that converts a wavelength of incident light and emits converted light. In the waveguide layer, a ridge waveguide and slab waveguides are provided, the slab waveguides being formed on both sides of the ridge waveguide with recess portions intervening therebetween. The waveguide layer satisfies a multi-mode condition for the incident light, and light propagating through the ridge waveguide is in a single mode.
    Type: Application
    Filed: December 22, 2003
    Publication date: May 25, 2006
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kiminori Mizuuchi, Kazuhisa Yamamoto, Minoru Imaeda, Tatsuo Kawaguchi, Takashi Yoshino
  • Regeneration control system
    Publication number: 20060102395
    Abstract: A regeneration control system permits highly efficient regeneration while a vehicle is traveling stably, and also permits regeneration to be performed without interfering with a smooth behavior correction made by a driver when the behavior of the vehicle has been disturbed. The regeneration control system includes a total regeneration amount determiner for determining the total regeneration amount of a first electric motor connected to front wheels and a second electric motor connected to rear wheels, a regeneration amount allocation determiner for determining regeneration amount allocation to each electric motor, a determination value calculator for calculating a determination value based on a steering angle and a yaw rate, and a determiner for determining whether a determination value lies within a predetermined range.
    Type: Application
    Filed: November 3, 2005
    Publication date: May 18, 2006
    Applicant: HONDA MOTOR CO., LTD.
    Inventors: Kazuhisa Yamamoto, Hirokatsu Amanuma, Akihiro Yamamoto
  • Drive control apparatus for hybrid vehicle
    Patent number: 7040433
    Abstract: A rotational shaft receives drive power from an engine and a first motor, and drives front wheels through front clutches. A second motor drives rear wheels. The first motor and the second motor are supplied with electric power from a battery. A main ECU controls an electric vehicle mode in which the first clutches are disengaged, the supply of fuel to the engine is stopped, and the second motor drives the rear wheels to propel a hybrid vehicle, by dividing the electric vehicle mode into a first propulsion mode and a second propulsion mode. In the first propulsion mode, the first motor is de-energized. In the second propulsion mode, a load imposed on the second motor is greater than that of the first propulsion mode, and the first motor is supplied with electric power to rotate the rotational shaft at a predetermined speed.
    Type: Grant
    Filed: December 24, 2003
    Date of Patent: May 9, 2006
    Assignee: Honda Motor Co., Ltd.
    Inventors: Kazuhisa Yamamoto, Nobuhiro Kira, Masao Kubodera, Yusuke Tatara