Patents by Inventor Akiyoshi Tobe

Akiyoshi Tobe 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: 20090009688
    Abstract: The present invention provides a liquid crystal display device which can largely enhance a property of focusing light from a backlight. The backlight arranged on a back surface of a liquid crystal panel includes a light guide plate, a light source, a first asymmetrical prism sheet, and a second asymmetrical prism sheet. A reflection surface having an inclination of 2° or less for guiding light from the light source toward the liquid crystal display panel is formed on a back surface of the light guide plate. The first asymmetrical prism sheet and the second asymmetrical prism sheet respectively include projecting portions which extend in the arrangement direction of the light source and are arranged in parallel to each other in the direction which intersects the arrangement direction of the light source.
    Type: Application
    Filed: July 2, 2008
    Publication date: January 8, 2009
    Inventors: Nobuyuki Koganezawa, Akiyoshi Tobe, Yasuhisa Shiraishi
  • Publication number: 20080165308
    Abstract: In a liquid crystal display device using a light emitting diode as a light source, even when a plurality of light emitting elements are provided, an inclined surface is formed on a light guide plate as a reflection surface, and a light is converged in the liquid-crystal-panel direction using the reflection surface. In a liquid crystal display device which includes a backlight for radiating a light toward a liquid crystal panel, LEDs are formed on the light guide plate which is mounted on the backlight as light emitting elements. The plurality of LEDs are arranged along a side surface of the light guide plate, and a first reflection surface and a second reflection surface are formed on a bottom surface of the light guide plate. The second reflection surface is arranged closer to the LEDs than the first reflection surface and an angle of the second reflection surface is set larger than an angle of the first reflection surface.
    Type: Application
    Filed: December 20, 2007
    Publication date: July 10, 2008
    Inventors: Yasuhisa Shiraishi, Akiyoshi Tobe, Nobuyuki Koganezawa
  • Publication number: 20070236957
    Abstract: The present invention provides a liquid crystal display device of high quality having high brightness and uniform brightness distribution by focusing the light radiation direction from a light guide plate in the vertical direction with respect to a light radiation surface of the light guide plate. The liquid crystal display device includes a liquid crystal display panel and a flat lighting device which radiates an illumination light to a back surface of the liquid crystal display panel. The flat lighting device includes a light guide plate which has an upper surface facing a back surface of the liquid crystal display panel in an opposed manner and constituting a light radiation surface and a bottom surface which is arranged opposite to the upper surface. One LED is arranged at a first corner portion of the light guide plate and another LED is arranged at a second corner portion of the light guide plate arranged adjacent to the first corner portion.
    Type: Application
    Filed: March 30, 2007
    Publication date: October 11, 2007
    Inventors: Nobuyuki Koganezawa, Akiyoshi Tobe
  • Publication number: 20070230214
    Abstract: The present invention makes a radiation angle of light at a portion of a light guide plate in front of an LED formed on one edge of a light guide plate and a radiation angle of light at a corner portion of the light guide plate equal to each other as much as possible. A shape of beam control elements which are arranged on a lower surface of a light guide plate is arranged concentrically about the LED.
    Type: Application
    Filed: March 29, 2007
    Publication date: October 4, 2007
    Inventors: Nobuyuki Koganezawa, Akiyoshi Tobe, Fumiyuki Sato
  • Publication number: 20070229729
    Abstract: The present invention provides a liquid crystal display device having a backlight device which can realize the high brightness and the high uniformity of in-plane brightness by allowing an optical sheet which is arranged above a light guide plate to effectively make use of light from spot light sources. An optical sheet is arranged between a side-light-type backlight device which includes a light guide plate and spot light sources on one side surface of the light guide plate and a liquid crystal display panel. The optical sheet is constituted of a sheet-like transparent base member and a plurality of convex lenses which are arranged on a backlight-device-side surface of the transparent base member. The convex lenses have a circular bottom surface shape and the centers of the bottom surfaces of the lenses are periodically arranged.
    Type: Application
    Filed: October 26, 2006
    Publication date: October 4, 2007
    Inventors: Seiichi Nishiyama, Hiroyuki Yoshida, Akiyoshi Tobe
  • Publication number: 20060244923
    Abstract: The present invention provides a display device having a large-area display region which is capable of performing an image display of high quality by making, even when two display panels abut on each other, an abutting portion becomes inconspicuous. Two optical path changing lenses LPL1, LPE2 are arranged in a state that respective optical path changing lenses LPL1, LPE2 have respective one sides thereof abutted on each other above an abutting portion BE of two display panels PNL1, PNL2. The abutted ends form a straight-line shape on the abutting portion BE.
    Type: Application
    Filed: April 21, 2006
    Publication date: November 2, 2006
    Inventors: Hideo Mitani, Yuuichi Kanesaka, Akiyoshi Tobe
  • Publication number: 20060114372
    Abstract: A liquid crystal display device includes a liquid crystal panel and an illumination device. The illumination device has a light guide plate and at least one spot light source on at least one side surface of the light guide plate. The light guide plate includes a large number of upper-surface arcuate cross-sectional grooves in a direction orthogonal to the one side surface on a surface thereof which faces the liquid crystal panel, and a large number of light-incident-surface arcuate cross-sectional grooves are formed in a thickness direction of the light guide plate on at least a portion of the one side surface which faces a position at which the spot light source is arranged. A relationship is provided between a contact angle Oa of the upper-surface arcuate cross-sectional grooves and a contact angle Ea of the light-incident-surface arcuate cross-sectional grooves.
    Type: Application
    Filed: November 28, 2005
    Publication date: June 1, 2006
    Inventors: Ken Saito, Shigeo Shimano, Hiroshi Nakamoto, Hiroyuki Yoshida, Hirokazu Yabe, Toshitsugu Miyawaki, Akiyoshi Tobe
  • Publication number: 20050195341
    Abstract: A display device includes an optical compensation sheet stacked body mounted on a back surface of a liquid crystal display panel, and a light guide plate mounted on a back surface of the optical compensation sheet stacked body. A first air layer is interposed between the optical compensation sheet stacked body and the light emitting surface of the light guide plate, and a plurality of diffusion plates are mounted on the light incident surface of the light guide plate. A reflection sheet is arranged to face the light guide plate, and an array of an LED chips is provided on a front surface of the reflection sheet. A second air layer is interposed between the light diffusion plates and the LED array. Light from the LED chips having a plurality of colors is mixed and effective optical path length can be prolonged, whereby the least coupling loss is obtained.
    Type: Application
    Filed: March 2, 2005
    Publication date: September 8, 2005
    Inventors: Nobuyuki Koganezawa, Hiroshi Tokuyama, Akiyoshi Tobe
  • Patent number: 6624559
    Abstract: There is provided a cathode ray tube capable of displaying high quality images by suppressing eddy current from occurring and by realizing the velocity modulation. A cylindrical focusing electrode is divided into first cylindrical focusing electrode 4B and second cylindrical focusing electrode 4T and the gap between the both electrodes formed and divided by optimizing the length of the second cylindrical focusing electrode 4T in the tube axial direction is enlarged substantially to increase the infiltration of the velocity modulating magnetic field to the non-electric space of the focusing electrode 4. An electrode 4a having the equal potential with the focusing electrode 4 is disposed at the gap to suppress eddy current from being generated.
    Type: Grant
    Filed: April 3, 2001
    Date of Patent: September 23, 2003
    Assignees: Hitachi Ltd, Hitachi Electronic Devices
    Inventors: Nobuyuki Suzuki, Toshio Nakayama, Yasuo Tanaka, Akiyoshi Tobe
  • Publication number: 20020096988
    Abstract: There is provided a cathode ray tube capable of displaying high quality images by suppressing eddy current from occurring and by realizing the velocity modulation. A cylindrical focusing electrode is divided into first cylindrical focusing electrode 4B and second cylindrical focusing electrode 4T and the gap between the both electrodes formed and divided by optimizing the length of the second cylindrical focusing electrode 4T in the tube axial direction is enlarged substantially to increase the infiltration of the velocity modulating magnetic field to the non-electric space of the focusing electrode 4. An electrode 4a having the equal potential with the focusing electrode 4 is disposed at the gap to suppress eddy current from being generated.
    Type: Application
    Filed: April 3, 2001
    Publication date: July 25, 2002
    Inventors: Nobuyuki Suzuki, Toshio Nakayama, Yasuo Tanaka, Akiyoshi Tobe
  • Patent number: 5814930
    Abstract: A color cathode ray tube having an in-line type electron gun includes an electron beam generating means having a plurality of electrodes and including at least a cathode for producing electron beams, a first electrode and a second electrode, both constituting control electrodes and arranged in that order, and a heater for heating the cathode; a third electrode, a fourth electrode and a fifth electrode, together constituting a first-stage focusing lens for focusing the three electron beams onto the phosphor screen; and a fifth electrode and a sixth electrode, both forming a second stage focusing lens. Electrical connections are made between the second electrode and the fourth electrode and between the third electrode and the fifth electrode. The first electrode has an aperture 0.
    Type: Grant
    Filed: May 27, 1997
    Date of Patent: September 29, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Kenichi Watanabe, Syoji Shirai, Shinichi Kato, Akiyoshi Tobe