Patents by Inventor Tetsuro Mizushima

Tetsuro Mizushima 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: 10319269
    Abstract: A laser light source device includes a semiconductor laser, a current supplying unit to supply a driving current to the semiconductor laser, and a signal generator to generate current intensity data for setting an intensity of the driving current. The signal generator generates, for an input signal corresponding to continuous pixels for a same color, a plurality of sets of the current intensity data indicating current intensities different from each other, and transmits the plurality of sets of the current intensity data to the current supplying unit while sequentially switching the plurality of sets of the current intensity data. The current supplying unit drives the semiconductor laser based on the plurality of different sets of the current intensity data.
    Type: Grant
    Filed: April 26, 2016
    Date of Patent: June 11, 2019
    Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
    Inventors: Takahisa Shiramizu, Tetsuro Mizushima, Junichi Mutoh, Susumu Uragami
  • Publication number: 20160343280
    Abstract: A laser light source device includes a semiconductor laser, a current supplying unit to supply a driving current to the semiconductor laser, and a signal generator to generate current intensity data for setting an intensity of the driving current. The signal generator generates, for an input signal corresponding to continuous pixels for a same color, a plurality of sets of the current intensity data indicating current intensities different from each other, and transmits the plurality of sets of the current intensity data to the current supplying unit while sequentially switching the plurality of sets of the current intensity data. The current supplying unit drives the semiconductor laser based on the plurality of different sets of the current intensity data.
    Type: Application
    Filed: April 26, 2016
    Publication date: November 24, 2016
    Inventors: TAKAHISA SHIRAMIZU, TETSURO MIZUSHIMA, JUNICHI MUTOH, SUSUMU URAGAMI
  • Patent number: 9188709
    Abstract: An object of the present invention is to provide an optical multiplexing apparatus and a projector that keep an optical system small, and easily adjust a number of light source units. The optical multiplexing apparatus has: a light source section that uses light source units to emit collimated beams; a first lens portion that converges the collimated beams which enter at different incident angles from each other to define converging positions; and a second lens portion that has focal points that correspond to the converging positions, respectively, wherein the first and second lens portions form an optical reduction system, and an optical axis of the second lens portion, which is directed to the corresponding focal point to one of the converging positions, extends along another optical axis of the second lens position, which is directed to the corresponding focal point to another of the converging positions.
    Type: Grant
    Filed: October 12, 2011
    Date of Patent: November 17, 2015
    Assignee: Panasonic Intellectual Property Management Co., Ltd.
    Inventors: Tatsuo Itoh, Tetsuro Mizushima
  • Patent number: 9048611
    Abstract: The present application discloses a wavelength conversion device. The wavelength conversion device includes a light source for generating excitation light, a laser medium for generating fundamental light from the excitation light, a resonator mirror for forming a resonator for the fundamental light in cooperation with the laser medium, and a wavelength convertor for converting wavelength from the fundamental light into harmonic light. The wavelength convertor includes a first end surface inclined by an angle ? from a surface orthogonal to an optical axis of the resonator and a second end surface parallel to the first end surface.
    Type: Grant
    Filed: April 2, 2012
    Date of Patent: June 2, 2015
    Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
    Inventors: Kenji Nakayama, Tetsuro Mizushima, Tatsuo Itoh, Hirohiko Oowaki, Tomohiro Matsuo
  • Patent number: 8976203
    Abstract: A wavelength conversion device includes an excitation light source that generates excitation light, a laser medium that generates fundamental light by means of the excitation light, two resonator mirrors that are disposed with the laser medium being interposed therebetween and resonate the fundamental light, a wavelength conversion element that is disposed between the two resonator mirrors and wavelength-converts the fundamental light to harmonic light, and a drive unit that generates a pulse modulation signal to pulse-drive the excitation light source. The laser medium is formed of a material having a thermo-optical effect and a positive thermo-optical constant. The pulse modulation signal generated by the drive unit has an initial interval including a rising edge of a pulse and a remaining interval subsequent to the initial interval. An average signal intensity during the initial interval is higher than an average signal intensity during the remaining interval.
    Type: Grant
    Filed: March 1, 2011
    Date of Patent: March 10, 2015
    Assignee: Panasonic Intellectual Property Management Co., Ltd.
    Inventors: Kenji Nakayama, Tetsuro Mizushima, Tatsuo Itoh, Hiroyuki Furuya
  • Patent number: 8955980
    Abstract: An image display apparatus includes: a laser light source for outputting a laser beam; a diffusion optical element for diffusing the laser beam; a drive unit for oscillating the diffusion optical element; and an image conversion unit for converting the laser beam output from the diffusion optical element into an image. The diffusion optical element disposed in the drive unit is oscillated and operated in a state where an amplitude of the drive of the drive unit, which is, for example, an amplitude that is driven in a direction of the arrow X in a plane that is perpendicular to an optical axis, is not constant.
    Type: Grant
    Filed: April 6, 2010
    Date of Patent: February 17, 2015
    Assignee: Panasonic Corporation
    Inventors: Kenji Nakayama, Tetsuro Mizushima, Tatsuo Itoh, Hiroyuki Furuya
  • Publication number: 20140247430
    Abstract: In an image display system, a light distribution forming lens is placed between a laser light source and a spatial light modulator or a MEMS mirror device for adjusting a distribution of light intensity of the laser light so that light intensity at an exit pupil of a projection lens is greater in a radially intermediate part thereof than in a central part thereof. The light distribution lens is provided with a conical incident surface and a convex exit surface so as to function also as a collimator lens. Thereby, the image display system can be constructed as a highly compact unit that is highly efficient in the use of available light and free from the problem of speckle noises.
    Type: Application
    Filed: February 3, 2014
    Publication date: September 4, 2014
    Applicant: PANASONIC CORPORATION
    Inventors: Masahiro INOUE, Tetsuro MIZUSHIMA
  • Patent number: 8807756
    Abstract: A laser projector includes a laser light source; a two-dimensional light modulator which modulates light from the laser light source; and a projection optical system which projects images onto a display plane by expanding the light modulated by the two-dimensional light modulator. Shift of a display position of the two-dimensional light modulation element and shift of the projection optical system are performed in synchronization with each other so that display positions of the images on the display plane are made substantially identical to each other. Thereby, speckle noise is sufficiently removed, and high-grade images are displayed.
    Type: Grant
    Filed: May 14, 2008
    Date of Patent: August 19, 2014
    Assignee: Panasonic Corporation
    Inventors: Tetsuro Mizushima, Tatsuo Itoh, Akira Koruzuka, Kazuhisa Yamamoto
  • Patent number: 8801194
    Abstract: A projector for projecting an image light including: a laser light source for emitting a laser beam; a light modulator for modulating the laser beam to generate the image light; a projection portion for projecting the image light; a detector for detecting a fixation degree of the projector; and a controller for controlling the power of the image light on the basis of the fixation degree.
    Type: Grant
    Filed: March 7, 2011
    Date of Patent: August 12, 2014
    Assignee: Panasonic Corporation
    Inventors: Kenji Nakayama, Tetsuro Mizushima, Tatsuo Itoh, Shinichi Kadowaki
  • Patent number: 8801189
    Abstract: There is provided a laser projector, including: a laser source section for emitting laser beams; a spatial light modulator which modulates the laser beams to generate image light; a projector lens from which the image light is emitted; a beam shaper which shapes the laser beams into a shape of the spatial light modulator; and a pupil uniformizer which makes a light intensity distribution uniform at an exit pupil of the projector lens, wherein the pupil uniformizer is situated between the laser source section and the beam shaper.
    Type: Grant
    Filed: June 20, 2011
    Date of Patent: August 12, 2014
    Assignee: Panasonic Corporation
    Inventors: Tetsuro Mizushima, Tatsuo Itoh, Kenichi Kasazumi, Kenji Nakayama
  • Patent number: 8767783
    Abstract: A light source device is provided with a coherent light source for emitting the coherent light, and a pattern changer for changing an interference pattern of the coherent light on a surface of the illumination object. The pattern changer includes a photorefractive crystal which is arranged between the coherent light source and the illumination object and on an optical path of the coherent light and exhibits a photorefractive effect, and a changer for changing at least one of a light intensity distribution, a polarization direction, a wavelength and an intensity of coherent light incident on the photorefractive crystal. The illumination object is illuminated with the coherent light.
    Type: Grant
    Filed: February 18, 2009
    Date of Patent: July 1, 2014
    Assignee: Panasonic Corporation
    Inventors: Koichi Kusukame, Tetsuro Mizushima, Kazuhisa Yamamoto, Hiroyuki Furuya, Shinichi Kadowaki, Kiminori Mizuuchi
  • Patent number: 8699123
    Abstract: A wavelength conversion laser light source 100 has: a laser light source configured to generate fundamental wave laser light; and a wavelength conversion element 101 provided with a periodic polarization reversal structure configured to convert the fundamental wave laser light which is incident onto the periodic polarization reversal structure into different laser light in wavelength wherein the wavelength conversion element includes different polarization reversal regions in period; and a polarization reversal axis 102 of at least one of the polarization reversal regions is inclined with respect to an incident optical path of the fundamental wave laser light on the wavelength conversion element.
    Type: Grant
    Filed: October 19, 2010
    Date of Patent: April 15, 2014
    Assignee: Panasonic Corporation
    Inventors: Koichi Kusukame, Tetsuro Mizushima, Nobuyuki Horikawa, Hiroyuki Furuya, Tomoya Sugita, Shinichi Kadowaki
  • Publication number: 20130329276
    Abstract: The present application discloses a wavelength conversion device. The wavelength conversion device includes a light source for generating excitation light, a laser medium for generating fundamental light from the excitation light, a resonator mirror for forming a resonator for the fundamental light in cooperation with the laser medium, and a wavelength convertor for converting wavelength from the fundamental light into harmonic light. The wavelength convertor includes a first end surface inclined by an angle ? from a surface orthogonal to an optical axis of the resonator and a second end surface parallel to the first end surface.
    Type: Application
    Filed: April 2, 2012
    Publication date: December 12, 2013
    Inventors: Kenji Nakayama, Tetsuro Mizushima, Tatsuo Itoh, Hirohiko Oowaki, Tomohiro Matsuo
  • Patent number: 8558956
    Abstract: An image display system comprises red, green and blue laser light sources, a spatial light modulator that modulates the laser light of different colors in a time sharing manner and a controller that controls the operation of the laser light sources and the spatial light modulator. The green and red laser light sources are lit in this order in each frame. The green color is diminished due to the response delay of the spatial light modulator, but the green laser light produced by the green laser light source has a relatively large color phase shift from the standard green color so that the shortage of green color cancels the color phase shift of the generated green color so that the color phase shift of the displayed intermediate color can be minimized.
    Type: Grant
    Filed: December 30, 2011
    Date of Patent: October 15, 2013
    Assignee: Panasonic Corporation
    Inventors: Yoshihiro Teshima, Yoshitaka Kitaoka, Takayuki Ooie, Tetsuro Mizushima
  • Patent number: 8446288
    Abstract: A light projection device, includes a movable projector section which illuminates or display information by projecting light while moving a projection position; a position detecting section which detects a position of a lost article instructed by a user; a view field detecting section which detects a view field of the user, and a controller section which controls said movable projection section based on the lost article detected by the position detecting section and the view field of the user detected by the view field detecting section, and either directly illuminates the lost article or projects guide information for guiding the user to the lost article within a view field of the user.
    Type: Grant
    Filed: September 30, 2009
    Date of Patent: May 21, 2013
    Assignee: Panasonic Corporation
    Inventors: Tetsuro Mizushima, Kazuhisa Yamamoto, Akira Kurozuka, Kakuya Yamamoto, Keiji Sugiyama, Kenji Nakayama
  • Patent number: 8440951
    Abstract: A wavelength conversion laser light source includes: a fundamental light source for outputting fundamental light; a wavelength conversion element with a nonlinear optical effect for converting the fundamental light into harmonic light of a different wavelength; a first optical receiver for receiving light of a specific polarization direction contained in the fundamental light output from the fundamental light source and converting an amount of light thereof into an electrical signal; a second optical receiver for receiving the harmonic light output from the wavelength conversion element and converting an amount of light thereof into an electrical signal; a temperature holding unit for holding a temperature of the wavelength conversion element constant; a fundamental light control unit for performing first control of controlling an amount of light of the fundamental light output from the fundamental light source based on the electrical signal from the second optical receiver, and second control of controlling
    Type: Grant
    Filed: July 8, 2009
    Date of Patent: May 14, 2013
    Assignee: Panasonic Corporation
    Inventors: Hiroyuki Furuya, Koichi Kusukame, Tetsuro Mizushima, Toshifumi Yokoyama, Kenji Nakayama, Kazuhisa Yamamoto, Shinichi Kadowaki, Tomoya Sugita, Nobuyuki Horikawa
  • Patent number: 8416363
    Abstract: It is aimed to provide an LCD backlight device and liquid crystal display that can suppress light quantity loss and ensure uniform brightness. An LCD backlight device 101 has a laser light source 1 that emits laser light, and a light guiding plate 3 that transforms the laser light from the laser light source 1 into linear laser light, and transforms the linear laser light into a planar laser light, and emits the planar laser light, and the light guiding plate 3 has a third side face 6 that transforms the linear laser light into the planar laser light by reflecting the linear laser light by a plurality of reflection surfaces that are formed along the entrance direction of the linear laser light.
    Type: Grant
    Filed: July 15, 2008
    Date of Patent: April 9, 2013
    Assignee: Panasonic Corporation
    Inventors: Shinichi Shikii, Tetsuro Mizushima, Tatsuo Itoh, Akira Kurozuka, Takayuki Nagata, Kazuhisa Yamamoto
  • Patent number: 8382296
    Abstract: An information processor includes a housing, a projector attached to the housing, and a screen attached to the housing, wherein the projector projects light onto the screen.
    Type: Grant
    Filed: August 6, 2010
    Date of Patent: February 26, 2013
    Assignee: Panasonic Corporation
    Inventors: Tatsuo Itoh, Tetsuro Mizushima, Kenji Nakayama, Tomoya Sugita, Hiroyuki Furuya, Shinichi Kadowaki, Yoshitaka Kitaoka, Kazumi Ohtsubo, Hirofumi Enomoto, Yuichi Hatase
  • Patent number: 8354204
    Abstract: The present invention provides a hologram recording material which attains high refractive index change, high flexibility, high sensitivity, low scattering, environment resistance, durability, low dimensional change and high multiplicity, and is suitable for volume hologram recording. Also, the present invention provides a hologram recording medium. A hologram recording material comprising: an organometallic compound at least containing at least two kinds of metals, oxygen, and an aromatic group and having an organometallic unit wherein two aromatic groups are bonded directly to one metal; and a photopolymerizable compound. One of the at least two kinds of metals is Si, and the metal(s) other than Si is/are preferably selected from the group consisting of Ti, Zr, Ge, Sn, Al and Zn. The organometallic unit is preferably a unit wherein two aromatic groups are bonded directly to one Si atom. A hologram recording medium (11) has a hologram recording material layer (21).
    Type: Grant
    Filed: April 25, 2005
    Date of Patent: January 15, 2013
    Assignee: TDK Corporation
    Inventors: Tetsuro Mizushima, Takuya Tsukagoshi, Hideaki Miura, Jiro Yoshinari
  • Patent number: 8351108
    Abstract: A wavelength conversion laser has: an exciting LD1, a solid state laser including a resonator, and a wavelength conversion element 7 disposed in the resonator. The solid state laser includes a first laser medium and a second laser medium as at least two types of laser media, and is configured to oscillate the solid state laser beams of the first emission wavelength and the second emission wavelength in the resonator as a result of the excitation light entering a region 3 configured from the first laser medium, thereafter entering a region 4 configured from the second laser medium, and subsequently entering a region 5 configured from the first laser medium. The wavelength conversion element 7 simultaneously generates a second harmonic and a sum frequency of the first emission wavelength and the second emission wavelength.
    Type: Grant
    Filed: June 9, 2010
    Date of Patent: January 8, 2013
    Assignee: Panasonic Corporation
    Inventors: Tetsuro Mizushima, Tatsuo Itoh, Kenji Nakayama, Koichi Kusukame, Tomoya Sugita