Patents by Inventor Ryusaku Takahashi

Ryusaku Takahashi 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: 6398365
    Abstract: A projection display apparatus (100) is formed by a light source (4) radiating white light w, a collimator lens (5) that converts condensed light flux from the light source (4) to collimated light flux, a cold mirror (6) for eliminating unwanted infrared light included in the white light w, an integrator that makes the intensity distribution of the illumination light on an object to be illuminated uniform, a reflective mirror (8) that reflects light flux from the integrator (7) at a prescribed angle, a polarizer (9) that polarizes separated light of each wavelength band, a spatial light modulation section (10), a coupling prism (11), and a projection lens (12).
    Type: Grant
    Filed: March 8, 2000
    Date of Patent: June 4, 2002
    Assignee: Victor Company of Japan, Limited
    Inventors: Ryusaku Takahashi, Shintaro Nakagaki, Tsutou Asakura, Fujiko Koyama
  • Patent number: 6283615
    Abstract: An Illumination apparatus according to the present invention is provided with a light source, a mirror that reflects a light emitted by the light source and converts it to a convergent light beam, and a collimator lens that collimates the convergent light beam reflected by the mirror to a collimated light beam. Here, the collimator lens is provided with a region positioned at a central region with respect to an optical axis and having a negative focal distance, and a plurality of concentric annular regions centering with respect to the optical axis and having focal distances different from each other.
    Type: Grant
    Filed: April 7, 2000
    Date of Patent: September 4, 2001
    Assignee: Victor Company of Japan, Limited
    Inventor: Ryusaku Takahashi
  • Patent number: 6174060
    Abstract: A color separating/light guiding optics comprises two independent dichroic mirrors, reflection mirrors and correcting lenses. A horizontal plane region occupied by these optical components is entirely involved in a horizontal plane region occupied by a light modulating/color compositing/image projecting optics. A red beam is guided along a detoured optical path extending across a dead space below a projection lens. Although the optical path length of the red beam becomes longer than those of the blue beam and the green beam, the detoured optical path provides a sufficient space for installing the correcting lenses. The substantial optical path lengths of three primary color beams can be equalized with each other by the provision of these correcting lenses.
    Type: Grant
    Filed: August 25, 1998
    Date of Patent: January 16, 2001
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Hirofumi Imaoka, Satoru Moriya, Tetsuji Suzuki, Fujiko Koyama, Ryusaku Takahashi, Yasuo Ishizaka, Motomu Takada
  • Patent number: 6141124
    Abstract: A color filter which, in a reflection type color picture projector using a polarized light component as a projection light, improve the utilization factor of light and a color picture display device using the same color filter are provided. The color filter 3 using a transmission type hologram diffracts and spectroscopically separates P polarized light components related to respective primary colors and condenses them to pixel electrodes 13r, 13g, and 13b on the side of an LCD panel 1. A reflection light which is modulated by an optical modulator 16 on the side of the LCD panel 1 and becomes S polarized light component is incident on the color filter 3. The color filter 3 transmits the S polarized light component and uses it as the projection light.
    Type: Grant
    Filed: October 23, 1997
    Date of Patent: October 31, 2000
    Assignees: Victor Company of Japan, Ltd., Hughes Aircraft Co.
    Inventors: Tetsuji Suzuki, Ryusaku Takahashi, Shintaro Nakagaki, John E. Gunther, Ronald T. Smith
  • Patent number: 6046856
    Abstract: In an illumination device used for a color image projector, indefinitely polarized light beams from a light source are separated by a polarization beam splitter into two linearly polarized light beams respectively having polarized planes perpendicularly intersecting to each other. One of the two polarized light beams is made to have the same polarized plane as that of the other by a 1/2.lambda. wave-plate. Second and third lens arrays are respectively placed at positions where an optical distance from a first lens array to the second lens array is the same as that from the first lens array to the third lens array. Principal rays of luminous fluxes outputted from microlenses of the second and third lens arrays are made to be parallel to each other and to a superimposing lens. The illumination light outputted from the superimposing lens illuminates a display device in a telecentric optical system using optically a visual field lens.
    Type: Grant
    Filed: December 9, 1998
    Date of Patent: April 4, 2000
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Ryusaku Takahashi, Tatsuru Kobayashi
  • Patent number: 5897190
    Abstract: This invention provide an image display apparatus having an illumination optical system for effectively illuminating a plurality of areas on a single common plane uniformly by shortening optical paths of the optical system and a new projection optical system capable of reducing the overall size of the optical system and a production cost thereof. The illumination optical system has an ellipse mirror for collecting light beams generated from a light source, a first lens group for suppressing divergence of the light beams reflected from a light collecting area of the ellipse mirror, a plural color filters for separating the light beams into three color light beams and altering a path of each of the three color light beams, and a second lens group for illuminating objects disposed on the single common plane by focusing the separated three color light beams thereon.
    Type: Grant
    Filed: September 13, 1996
    Date of Patent: April 27, 1999
    Assignee: Victor Company of Japan, Ltd.
    Inventor: Ryusaku Takahashi
  • Patent number: 5565882
    Abstract: An image processing system for an image display comprising an image data producing device for producing image data corresponding to an image to be displayed and a display device for displaying the image on the basis of the produced image data. The image data producing device divides the image data into a plurality of data sections respectively corresponding to image areas constituting the image so that each of the plurality of data sections is produced as serial data and the plurality of data sections are outputted in parallel. The display device includes a number of pixel elements continuously arranged one-dimensionally or two-dimensionally and equally divided into a plurality of element sections respectively corresponding to the plurality of data sections.
    Type: Grant
    Filed: March 9, 1995
    Date of Patent: October 15, 1996
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Itsuo Takanashi, Shintaro Nakagaki, Ichiro Negishi, Tetsuji Suzuki, Fujiko Tatsumi, Ryusaku Takahashi, Keiichi Maeno
  • Patent number: 5502490
    Abstract: A display unit includes a light-emitting element array having a plurality of linearly arranged light-emitting elements drivable by a time sequential image information signal to emit beams of light in accordance with pieces of information allotted to the corresponding picture elements, a deflector such as a polygon mirror for deflecting the light beams simultaneously in a direction perpendicular to the longitudinal direction of the light-emitting element array, and a light-to-light conversion element including a photoconductive layer and a photo-modulation layer, the light beams being imaged on the photoconductive layer.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: March 26, 1996
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Itsuo Takanashi, Shintaro Nakagaki, Ichiro Negishi, Tetsuji Suzuki, Fujiko Tatsumi, Ryusaku Takahashi, Keiichi Maeno
  • Patent number: 5486878
    Abstract: In a color image display apparatus, light beams intensity modulated by a green color image signal are deflected by an ocillating mirror, and then focused on a photo-conductive layer (PCL) member of a light-written type spacial light modulation element (SLM) through two focusing lenses for light write operation. Light beams intensity modulated by a time-axis compressed time-divisional image signal of two remaining colors (red and blue) are deflected by another mirror oscillated simultaneously with the ocillating mirror, and then focused on a PCL member of a SLM of the same type through two focusing lenses for light write operation. A read light beam is resolved into the light of the green wave length band and the lights of red and blue wave length bands, respectively, and then given to the SLMs, respectively for light read operation. The two read light beams reflected by the SLMs are synthesizing, and then projected on a screen through a common projection lens.
    Type: Grant
    Filed: September 23, 1994
    Date of Patent: January 23, 1996
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Ichiro Negishi, Tetsuji Suzuki, Fujiko Koyama, Yuji Uchiyama, Hiroyuki Bonde, Toshio Konno, Ryusaku Takahashi, Toshiaki Shou
  • Patent number: 5463468
    Abstract: A display unit includes a light-emitting element array having a plurality of linearly arranged light-emitting elements drivable by a time sequential image information signal to emit beams of light in accordance with pieces of information allotted to the corresponding picture elements, a deflector such as a polygon mirror for deflecting the light beams simultaneously in a direction perpendicular to the longitudinal direction of the light-emitting element array, and a light-to-light conversion element including a photoconductive layer and a photo-modulation layer, the light beams being imaged on the photoconductive layer.
    Type: Grant
    Filed: March 16, 1994
    Date of Patent: October 31, 1995
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Itsuo Takanashi, Shintaro Nakagaki, Ichiro Negishi, Tetsuji Suzuki, Fujiko Tatsumi, Ryusaku Takahashi, Keiichi Maeno
  • Patent number: 5381188
    Abstract: The present invention offers a display system for displaying information comprising a linear array of N light-emitting devices emitting light of predetermined wavelength, the devices are arranged respectively with N pixels, a stream of the information is divided into pieces each of which containing the N pixels, and the N light-emitting devices are caused to emit N light beams simultaneously in a form of array during a given period for every divided piece of the information, the every divided piece of information may correspond to one line of a frame of picture, the N light beams are intensity-modulated respectively with the divided piece of the information, the N light beams are deflected simultaneously in a direction perpendicular to a direction of the array of the N light beams, and a spatial light modulator having a photoconductive layer and a light modulation layer interposed between a pair of electrodes, the photoconductive layer is responsive to the deflected N light beams incident thereto through a fo
    Type: Grant
    Filed: May 4, 1992
    Date of Patent: January 10, 1995
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Toshio Konno, Shintaro Nakagaki, Ichiro Negishi, Tetsuji Suzuki, Fujiko Tatsumi, Ryusaku Takahashi, Keiichi Maeno
  • Patent number: 5379135
    Abstract: An optical system is disclosed which is for a display apparatus having a light source for emitting read light and a reflection type spatial light modulator for modulating the read light incoming thereto into in accordance with image written thereon. The modulated light is projected onto a screen by a projection lens to display the image. A field lens is provided between the modulator and screen at such a position that both the read and modulated light pass therethrough. The field lens focuses the modulated light on near an entrance pupil of the projection lens so that the intensity of the modulated light is increased.
    Type: Grant
    Filed: March 24, 1993
    Date of Patent: January 3, 1995
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Shintaro Nakagaki, Ichiro Negishi, Tetsuji Suzuki, Fujiko Tatsumi, Ryusaku Takahashi, Hiroyuki Bonde, Tsutomu Matsumura
  • Patent number: 5357289
    Abstract: This specification discloses an image projector for projecting a tri-color composite optical image on a screen as a magnified optical image. A reading light beam emitted from a light source is separated into three color beams, e.g., Red, Green and Blue color beams through a tri-color separation and composition optical system. The separated color beams are irradiated on image forming devices provided correspondingly with Red, Green and Blue color images to read out color images respectively therefrom. Each of the reflected light beams from the image forming device carrying color image information impinges again on the tri-color separation and composition optical system to compose a composite image beam. The composite image beam is projected on the screen through an optical lens system comprising a first lens group, a second lens group and a third lens group disposed along an optical axis in order.
    Type: Grant
    Filed: January 13, 1994
    Date of Patent: October 18, 1994
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Toshio Konno, Shintaro Nakagaki, Ighiro Negishi, Tetsuji Suzuki, Fujiko Tatsumi, Ryusaku Takahashi, Keiichi Maeno
  • Patent number: 5327229
    Abstract: A clear color image having a high contrast ratio without particular coloration is displayed on a screen by improved display apparatus. Such display apparatus is comprised of a spatial light modulator including a photo-conductive layer, a photo-modulator layer and a dielectric mirror, a device for writing color images of different colors onto the spatial light modulator time-divisionally in a sequence of the different colors, a reading device for producing reading lights having different colors in synchronism with time-divisional writing of the color images, and for projecting the reading lights to the spatial light modulator, a driving device for supplying the spatial light modulator with different voltages and frequencies correspondingly with the reading light of different colors and in synchronism with time-divisional projections of the reading lights, and a device for projecting the color images read out from the spatial light modulator on the display device.
    Type: Grant
    Filed: February 11, 1993
    Date of Patent: July 5, 1994
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Toshio Konno, Shintaro Nakagaki, Ichiro Negishi, Tetsuji Suzuki, Fujiko Tatsumi, Ryusaku Takahashi, Hiroyuki Bonde, Tsutomu Matsumura
  • Patent number: 5325137
    Abstract: An overhead projector for irradiating a spatial light modulator with reading light to read out a subject image written in the spatial light modulator with writing light and projecting the subject image read out with the reading light, wherein the spatial light modulator consists of photoconductive layer for receiving the writing light coming from a subject to reproduce the subject image, light modulating layer formed by a liquid crystal of which molecules are arranged in a homeotropic orientation for modulating the reading light of which a waveband is limited to a prescribed range according to the subject image reproduced in the photoconductive layer, and a dielectric mirror having wavelength selectivity for reflecting the reading light with the waveband modulated by the light modulating layer.
    Type: Grant
    Filed: August 27, 1992
    Date of Patent: June 28, 1994
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Toshio Konno, Shintaro Nakagaki, Ichiro Negishi, Tetsuji Suzuki, Fujiko Tatsumi, Ryusaku Takahashi
  • Patent number: 5305146
    Abstract: Color separating or composing optical system having an optical axis wherein at least one color filter is placed obliquely to the optical axis to perform color separation or composition by color-selective reflection and passing of lights proceeding along the optical axis, a cylindrical lens is placed in an optical path of a light passing the color filter, another feature of this invention is that two color filters are placed obliquely with respect to the optical axis to perform color separation or composition by color-selective reflection and passing of lights proceeding along the optical axis, and are arranged in configuration as such that an imaginary plane defined to include the optical axis and a line perpendicular to one of the two color filters, is perpendicular to another imaginary plane defined to include the optical axis and another line perpendicular to the other of the two color filters.
    Type: Grant
    Filed: June 24, 1992
    Date of Patent: April 19, 1994
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Shintaro Nakagaki, Tsutou Asakura, Ryusaku Takahashi, Tetsuji Suzuki, Fujiko Tatsumi
  • Patent number: 5299042
    Abstract: A display unit which can be used with various sources of information includes a light-to-light conversion element composed of first and second stripe electrodes arranged to jointly form a matrix electrode, and a photoconductive layer and a light modulation layer disposed between the first and second stripe electrodes, the impedance of the photoconductive layer changes with information written to the light-to-light conversion element. The photoconductive layer is irradiated with a linear light beam deflected in a direction to intersect first stripe electrode, while at the same time successive pieces of information to be inputted to corresponding picture elements are supplied to respective stripe electrode elements of the first stripe electrode. With the use of the matrix electrode, information can be written to and read out from the light-to-light conversion element at a higher response rate with high resolution.
    Type: Grant
    Filed: May 30, 1991
    Date of Patent: March 29, 1994
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Itsuo Takanashi, Shintaro Nakagaki, Ichiro Negishi, Tetsuji Suzuki, Fujiko Tatsumi, Ryusaku Takahashi
  • Patent number: 5294992
    Abstract: A light-light transfer method using a spatial light modulator realizes an image display with a high utilizing of light without causing an undesirable residual image. The spatial light modulator is constituted to include two electrodes and at least a photoconductor layer member and a photo-modulation layer member used in a birefringence operating mode both being sandwiched between the two electrodes. A writing light is entered from the photoconductive layer member side so that its exposure value varies from the minimum exposure value to the maximum exposure value in a condition that a predetermined operation voltage is supplied between the two electrodes. In this instant, a voltage applied between both ends of the photo-modulation layer member corresponds to a voltage obtained by subtracting a voltage drop amount, occurring in the photoconductor layer member due to an incidence of the writing light, from said predetermined operation voltage applied in advance between said two electrodes.
    Type: Grant
    Filed: May 4, 1992
    Date of Patent: March 15, 1994
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Toshio Konno, Shintaro Nakagaki, Ichiro Negishi, Tetsuji Suzuki, Fujiko Tatsumi, Ryusaku Takahashi, Keiichi Maeno
  • Patent number: 5285268
    Abstract: A display device of projection type capable of projecting an image with well defined image frame is disclosed. The device comprises 3 spatial light modulators on which color image information is written in 3 primary colors respectively and is read out as a combined optical color image in a form of light beam, the light beam is then projected out of the display device through lens groups for forming a projected image on a screen, the device further comprises a mask disposed in a proximity of an imaginary image formation plane arranged to locate in a vicinity of one of the lens groups, the light beam is caused to form an optical image on the imaginary image formation plane. The mask has a variable light shielding configuration controlled either electronically or electro-mechanically for cutting off unnecessary light portions of the light beam carrying the optical image so that an image of high contrast and well defined clear fringe is projected on the screen.
    Type: Grant
    Filed: December 9, 1992
    Date of Patent: February 8, 1994
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Shintaro Nakagaki, Ichiro Negishi, Tetsuji Suzuki, Fujiko Tatsumi, Ryusaku Takahashi, Hiroyuki Bonde, Tsutomu Matsumura
  • Patent number: 5264951
    Abstract: There is provided an optical system for a spatial light modulator. The system comprises a light source for emitting an unpolarized light, a separator for separating a first linearly polarized light having a specified plane of polarization from the unpolarized light and polarizer for rotating the plane of polarization of the first linearly polarized light at a specified angle different from the specified angle to obtain a second linearly polarized light, wherein the second linearly polarized light is adopted as a reading light. Also provided is a method of photomodulation, comprising the steps of separating a light in the region of a specified wavelength from an unpolarized light, separating a first linearly polarized light having a specified plane of polarization from the light and obtaining a second linearly polarized light by rotating the plane of polarization of the first linearly polarized light at a specified angle.
    Type: Grant
    Filed: November 23, 1992
    Date of Patent: November 23, 1993
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Itsuo Takanashi, Shintaro Nakagaki, Ichiro Negishi, Ryusaku Takahashi, Tetsuji Suzuki, Fujiko Tatsumi, Keiichi Maeno