Patents by Inventor Shoichi Hirota

Shoichi Hirota 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: 7990369
    Abstract: An image display apparatus configured by a display panel having an image memory element in a pixel, which achieves low power consumption. A nonvolatile image memory element 1, which can change the resistance value by phase change, is connected to a pixel electrode 25 of a liquid crystal element 5. The output of a thin-film transistor 17 driven by scanning and signal electrode lines 7, 9 is connected to the pixel electrode 25. When the scanning electrode line 7 is selected to have a high level voltage, the thin-film transistor 17 is turned on and a current signal flowing through the signal electrode 9 is sent through the image memory element 1 to a reference electrode line 15. Depending on the current value or pulse width passing through the image memory element 1, the resistance of the image memory element 1 is changed and is stored as a resistance value.
    Type: Grant
    Filed: May 24, 2007
    Date of Patent: August 2, 2011
    Assignee: Hitachi Displays, Ltd.
    Inventors: Tatsuya Sugita, Shinichi Komura, Shoichi Hirota, Tsunenori Yamamoto, Tetsuya Ooshima, Susumu Edo, Akitoyo Konno
  • Patent number: 7982832
    Abstract: The present invention enhances display efficiency and a contrast of a reflective part in an IPS-type transflective liquid crystal display device.
    Type: Grant
    Filed: January 31, 2007
    Date of Patent: July 19, 2011
    Assignee: Hitachi Displays, Ltd.
    Inventors: Hirotaka Imayama, Tetsuya Nagata, Osamu Itou, Shoichi Hirota
  • Patent number: 7952663
    Abstract: In a transflective liquid crystal display device having a first substrate, a second substrate, a liquid crystal layer disposed between the two substrates and a reflective region and a transmissive region in each pixel; the second substrate has a pixel electrode to drive the liquid crystal layer and a common electrode; the reflective region of the second substrate is formed with an in-cell polarizer between the pixel electrode and common electrode and the reflector. In this invention, the thickness of the liquid crystal layer is set greater in the reflective region than in the transmissive region. The difference in the liquid crystal layer thickness between the reflective region and the transmissive region is provided by forming a step in the first substrate or the second substrate.
    Type: Grant
    Filed: January 25, 2008
    Date of Patent: May 31, 2011
    Assignee: Hitachi Displays, Ltd.
    Inventors: Chieko Araki, Masaya Adachi, Osamu Itou, Shoichi Hirota, Shinichiro Oka, Jun Tanaka, Miharu Otani
  • Patent number: 7884908
    Abstract: Each pixel has a transmissive area and a reflective area. A first alignment process area and a second alignment process area are placed such that an overlapping region is created in part of the reflective area. A region where the liquid crystal alignment direction shifts continuously is created in a boundary between the transmissive are a and the reflective are a without exception. A first liquid crystal alignment region is formed wider than the transmissive area, and a second liquid crystal alignment region is formed narrower than the reflective area.
    Type: Grant
    Filed: December 23, 2008
    Date of Patent: February 8, 2011
    Assignee: Hitachi Displays, Ltd.
    Inventors: Shoichi Hirota, Masaki Matsumori, Tetsuya Nagata, Shinichiro Oka
  • Patent number: 7859527
    Abstract: A reference voltage line is synchronously scanned with scanning of a scanning signal line, voltage of the reference voltage line is set to be the voltage of a common electrode, the second transistor is set to be OFF state during the reference voltage line is set in the common voltage for a pixel wherein a node between an image signal memory and said second transistor is set in a voltage so that said second transistor becomes OFF and the voltage of image signal line is set to be high voltage level when the voltage of the scanning signal line changes from low voltage level to high voltage level for the pixel wherein the node between the image signal memory and the second transistor is set in a voltage so that said second transistor becomes ON.
    Type: Grant
    Filed: September 21, 2004
    Date of Patent: December 28, 2010
    Assignee: Hitachi Displays, Ltd.
    Inventors: Shoichi Hirota, Susumu Edo, Hiroki Kaneko, Tetsuya Oshima, Tatsuya Sugita, Shinichi Komura, Katsuyuki Funahata
  • Patent number: 7808466
    Abstract: The present invention provides an IPS-type transflective liquid crystal display device in which a contrast is not inverted between a transmissive portion and a reflective portion. The transflective liquid crystal display device includes a liquid crystal display panel having a pair of substrates and liquid crystal which is sandwiched between the pair of substrates, wherein the liquid crystal display panel includes the plurality of sub pixels each of which includes a transmissive portion and a reflective portion, each sub pixel of the plurality of sub pixels includes a pixel electrode which is formed on one substrate out of the pair of substrates and a counter electrode which is formed on the one substrate, and an electric field is generated between the pixel electrode and the counter electrode thus driving the liquid crystal.
    Type: Grant
    Filed: November 6, 2006
    Date of Patent: October 5, 2010
    Assignee: Hitachi Displays, Ltd.
    Inventors: Masateru Morimoto, Toshio Miyazawa, Shoichi Hirota
  • Patent number: 7777844
    Abstract: A transflective liquid crystal display device is arranged to make the overall structure thinner and enhance a reflecting contrast ratio. The transflective liquid crystal display includes a first substrate, a second substrate, a liquid crystal layer laid between the substrates, a first polarization plate located on the opposite side of the first substrate to the side where the liquid crystal layer is located, a second polarization plate located on the opposite side of the second substrate to the side where the liquid crystal layer is located, and a plurality of pixels formed between the substrates, each of the pixels having a reflective area and a transmissive area. An in-cell retarder is located between the second substrate and the liquid crystal layer. An optical compensation film is located between the first substrate and the first polarization plate, between the second substrate and the second polarization plate, or both.
    Type: Grant
    Filed: January 23, 2008
    Date of Patent: August 17, 2010
    Assignee: Hitachi, Displays, Ltd.
    Inventors: Shinichiro Oka, Osamu Itou, Shoichi Hirota
  • Patent number: 7751014
    Abstract: This invention includes a first substrate, a second substrate, a liquid-crystal layer sandwiched between the first substrate and the second substrate, and a plurality of pixels each surrounded by scan lines and signal lines arranged in a matrix format on the second substrate; with a first pixel electrode, a second pixel electrode, a first common electrode, and a second common electrode being arranged in the pixel region of the second substrate above which the liquid-crystal layer is disposed, the first pixel electrode and the first common electrode being arranged on a first layer, the second pixel electrode and the second common electrode being arranged on a second layer, the first pixel electrode and the second common electrode being overlapped upon each other in the pixel region, and the second pixel electrode and the first common electrode being overlapped upon each other in the pixel region.
    Type: Grant
    Filed: July 30, 2008
    Date of Patent: July 6, 2010
    Assignee: Hitachi Displays, Ltd.
    Inventors: Shinichiro Oka, Osamu Itou, Shoichi Hirota
  • Patent number: 7728922
    Abstract: The present invention provides a liquid crystal display device in which increase in manufacturing costs is minimized and the utilization rate of illumination light emitted by a backlight source is also improved. A pixel electrode is formed at the intersection of each signal line and each gate line on the liquid-crystal-layer side of a first transparent substrate. A color filter is provided for each pixel electrode on the liquid-crystal-layer side of a second transparent substrate. A dichroic half mirror is provided for each of the color filters.
    Type: Grant
    Filed: May 2, 2008
    Date of Patent: June 1, 2010
    Assignee: Hitachi Displays, Ltd.
    Inventors: Shoichi Hirota, Tatsuya Sugita
  • Patent number: 7710376
    Abstract: A display with low power consumption using a memory-incorporated pixel system capable of refreshing the image signal memory and updating an image without causing a flicker. Each pixel arranged in matrix has, at an intersection between the signal line and the scan line, a first transistor and a second transistor to drive the electrooptical medium. The second transistor has its gate connected with the image signal memory which in turn is connected to the reference voltage line. There is a parasitic capacitor between the gate of the second transistor and the scan line. The gate of the second transistor is also connected with an added capacitor. Further, the second transistor is connected with a holding capacitor and also has a parasitic capacitor.
    Type: Grant
    Filed: February 13, 2006
    Date of Patent: May 4, 2010
    Assignee: Hitachi Displays, Ltd.
    Inventors: Susumu Edo, Shoichi Hirota
  • Publication number: 20100090220
    Abstract: The present invention aims at providing a high-performance semiconductor device such as display, IC tag, sensor or the like at a low cost by using an organic thin film transistor most members of which can be formed by printing, as a switching element. The present invention relates to a thin film transistor composed of members on a dielectric substrate, which are a gate electrode, a dielectric film, source/drain electrodes, and a semiconductor layer, wherein on said semiconductor layer there are formed at least two passivation films of a first passivation film capping said semiconductor layer to protect it and a second passivation film covering larger area than that of said first passivation film to protect all of said members.
    Type: Application
    Filed: December 15, 2009
    Publication date: April 15, 2010
    Applicant: HITACHI, LTD.
    Inventors: Masahiro KAWASAKI, Shuji Imazeki, Masahiko Ando, Yoshifumi Sekiguchi, Shoichi Hirota
  • Patent number: 7675596
    Abstract: A semi-transparent homogeneous-alignment LCD device including a transmission part and a reflection part, a first linear dielectric protrusion disposed between a common electrode and a liquid crystal layer so as to extend over a plurality of pixels in a short side direction of pixels and be disposed nearly in center of the transmission part, and a second linear dielectric protrusion disposed in the reflection part between the common electrode and a first substrate so as to extend over a plurality of pixels in the short side direction, wherein an alignment direction of liquid crystal molecules crosses the first and second linear dielectric protrusions at right angles and is parallel to a long side direction of pixels, and a tilt angle of the liquid crystal molecules is approximately 0°, or even if there is a pre-tilt angle, the tilt angle of the liquid crystal molecules is 2° or less.
    Type: Grant
    Filed: August 17, 2006
    Date of Patent: March 9, 2010
    Assignee: Hitachi Displays, Ltd.
    Inventors: Shoichi Hirota, Osamu Itou, Shinichiro Oka, Masaya Adachi, Shinichi Komura, Hirotaka Imayama, Masateru Morimoto, Tetsuya Nagata, Koichi Fukuda, Toshio Miyazawa
  • Patent number: 7656483
    Abstract: A transreflective or “semi-transmissive” liquid crystal display (LCD) device of the vertical alignment (VA) type is disclosed. The VA-LCD device includes a pair of spaced-apart substrates with a layer of liquid crystal (LC) material sandwiched therebetween. The LCD device also includes a polarization plate provided on one of the substrates, another polarization plate on the other substrate, and a matrix of rows and columns of pixels formed between the substrates. Each pixel has a reflection part and a transmission part. The LC layer is variable in thickness so that its portion at the transmission part is thicker than a portion at the reflection part. At the reflection part, an internal retardation plate having an optical phase difference is disposed between the LC layer and its associated substrate. This plate forms an angle of about 45 degrees with the absorption axis of each polarization plate.
    Type: Grant
    Filed: August 10, 2007
    Date of Patent: February 2, 2010
    Assignee: Hitachi Displays, Ltd.
    Inventors: Shinichiro Oka, Osamu Itou, Shoichi Hirota
  • Patent number: 7639320
    Abstract: In a liquid crystal display device, rays of light of a light source for blue light emission are concentrated on a fluorescent material by using a lens of a first micro-lens array and fluorescent rays from the fluorescent material are concentrated on a pixel of corresponding color by using a lens of a second micro-lens array.
    Type: Grant
    Filed: October 10, 2007
    Date of Patent: December 29, 2009
    Assignee: Hitachi Displays, Ltd.
    Inventors: Osamu Itou, Tatsuya Sugita, Masaya Adachi, Shinichi Komura, Shoichi Hirota
  • Patent number: 7599027
    Abstract: A transflective liquid crystal display device includes a liquid crystal display panel having a first substrate, a second substrate, and a liquid crystal interposed between the first substrate and the second substrate in which the liquid crystal display panel includes a plurality of subpixels having a transmissive portion and a reflective portion, wherein the transmissive portion of each of the plurality of subpixels includes a first common electrode formed on the first substrate, and a transmissive pixel electrode formed on the first common electrode through an interlayer insulating film, wherein the transmissive pixel electrode has a plurality of pectinate electrodes or slits, and wherein the reflective portion of each of the plurality of subpixels includes a reflective electrode formed on the first common electrode, a planar reflective pixel electrode formed on the first common electrode through the interlayer insulating film, second common electrodes formed on the second substrate, and a retarder formed be
    Type: Grant
    Filed: October 29, 2007
    Date of Patent: October 6, 2009
    Assignee: Hitachi Displays, Ltd.
    Inventors: Koichi Igeta, Hitoshi Komeno, Shinichi Komura, Shoichi Hirota, Osamu Itou, Shinichiro Oka
  • Patent number: 7573553
    Abstract: In a transflective type IPS type liquid crystal display device in which a phase difference layer has been built in a reflection display portion, a retardation value of the phase difference layer corresponding to a short wavelength color filter is different from a retardation value of the phase difference layer corresponding to a long wavelength color filter; while a blue display pixel is set to the short wavelength color filter and both red and green pixels are set to the long wavelength filter, the retardation value of the phase difference layer corresponding to the former-mentioned short wavelength color filter is made smaller than the retardation value of the phase difference layer corresponding to the latter-mentioned long wavelength color filter.
    Type: Grant
    Filed: November 6, 2007
    Date of Patent: August 11, 2009
    Assignee: Hitachi Displays, Ltd.
    Inventors: Osamu Itou, Shoichi Hirota, Masaya Adachi, Shinichiro Oka
  • Publication number: 20090168002
    Abstract: Each pixel has a transmissive area and a reflective area. A first alignment process area and a second alignment process area are placed such that an overlapping region is created in part of the reflective area. A region where the liquid crystal alignment direction shifts continuously is created in a boundary between the transmissive are a and the reflective are a without exception. A first liquid crystal alignment region is formed wider than the transmissive area, and a second liquid crystal alignment region is formed narrower than the reflective area.
    Type: Application
    Filed: December 23, 2008
    Publication date: July 2, 2009
    Inventors: Shoichi Hirota, Masaki Matsumori, Tetsuya Nagata, Shinichiro Oka
  • Patent number: 7522146
    Abstract: A scanning-line selecting circuit is configured by connecting basic circuits with each other over plural stages. Each of the basic circuits includes a basic scanning-line driving circuit and a voltage raising circuit. A basic scanning signal is inputted into the basic scanning-line driving circuit, which, then, outputs a scanning signal. A charge pulse, a selecting signal, and a discharge pulse are inputted into the voltage raising circuit, which, then, drives the basic scanning-line driving circuit. Accordingly, in the basic circuits, there exists none of the problems of threshold-value shift and voltage lowering. This characteristic makes it possible to implement high efficiency and stable operation.
    Type: Grant
    Filed: December 3, 2004
    Date of Patent: April 21, 2009
    Assignee: Hitachi Displays, Ltd.
    Inventors: Susumu Edo, Shinichi Komura, Shoichi Hirota, Nobuyuki Ishige
  • Patent number: 7508370
    Abstract: An active matrix type liquid crystal display device driving method for switching a partial display mode and a normal display mode. The respective data lines of the partial display area are scanned in a certain period defined as a frame period, “k” pieces (symbol “k” is integer larger than, or equal to 1) of the partial display areas are present within 1 screen, a common electrode potential is varied 2k times within 1 frame period; a common electrode potential in a partially scanning period for scanning the partial display area is made as a constant potential against a reference of a driving circuit for driving the data lines; and within at least two continued frames, a common electrode potential of a blank period other than the partially scanning period is made as a constant potential which is different from the constant potential in the partially scanning period.
    Type: Grant
    Filed: June 9, 2005
    Date of Patent: March 24, 2009
    Assignee: Hitachi Displays, Ltd.
    Inventors: Yoshifumi Sekiguchi, Shoichi Hirota, Shinichi Komura
  • Publication number: 20090033848
    Abstract: To provide a highly efficient liquid-crystal display device wide in viewing angle and minimized in color shifting. This invention includes a first substrate, a second substrate, a liquid-crystal layer sandwiched between the first substrate and the second substrate, and a plurality of pixels each surrounded by scan lines and signal lines arranged in a matrix format on the second substrate; with a first pixel electrode, a second pixel electrode, a first common electrode, and a second common electrode being arranged in the pixel region of the second substrate above which the liquid-crystal layer is disposed, the first pixel electrode and the first common electrode being arranged on a first layer, the second pixel electrode and the second common electrode being arranged on a second layer, the first pixel electrode and the second common electrode being overlapped upon each other in the pixel region, and the second pixel electrode and the first common electrode being overlapped upon each other in the pixel region.
    Type: Application
    Filed: July 30, 2008
    Publication date: February 5, 2009
    Inventors: Shinichiro Oka, Osamu Itou, Shoichi Hirota