Patents by Inventor Hiroaki Asuma

Hiroaki Asuma 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: 20050200582
    Abstract: A display device includes sub-pixels, video lines, a drive circuit and switch groups. The video lines are divided into plural blocks each composed of m video lines, m being an integer of 2 or more. The drive circuit outputs m gray scale voltages time-sequentially. Each of the switch groups corresponding to one of the blocks is composed of first to mth switches, receives the m gray scale voltages from the drive circuit, and then supplies them to the m video lines in a time-division multiplexed fashion. The mth switch is turned on last during a writing time for writing. the m gray scale voltages into the sub-pixels, and Tq<Tm, where Tm and Tq are times during which the mth switch and a qth switch of the first to (m?1)th switches are turned on, respectively, and q is an integer of from 1 to ( m?1).
    Type: Application
    Filed: February 23, 2005
    Publication date: September 15, 2005
    Inventors: Kazutaka Goto, Hiroaki Asuma, Atsushi Hasegawa
  • Publication number: 20050190315
    Abstract: A display devices which exhibits improved image qualities has a pair of substrates which sandwich a liquid crystal layer there between. On one of the substrates there are a plurality of video signal lines, a plurality of pixel electrodes which are arranged in a matrix array and to which video signals are supplied from the video signal lines, and a plurality of conductive layers, which are provided at positions where portions thereof overlap with the video signal lines by way of an insulation film. The respective conductive layers are electrically connected to respective video signal lines. Further, the conductive layer is able to prevent light irradiated from a backlight from leaking through a gap defined between two neighboring pixel electrodes.
    Type: Application
    Filed: July 24, 2003
    Publication date: September 1, 2005
    Inventors: Hiroaki Asuma, Atsushi Hasegawa, Toshio Miyazawa
  • Patent number: 6642988
    Abstract: For suppressing a brightness irregularity and contrast deterioration in a displaying screen of a liquid crystal display device which comprises a pair of substrates at least one of which is transparent, at least two kinds of color filters being formed on one of the pair of substrates, a black matrix being provided between the color filters, a group of electrodes being formed on either one of the pair of substrates, a layer of liquid crystal compounds sealed between the pair of substrates, due to noise electrical field appearing therein or unevenness of a cell gap between the pair of substrates, the present invention provides a columnar spacer having smaller resistivity than that of the liquid crystal compounds in a part of an area on the one of the pair of substrates which is hidden by the black matrix.
    Type: Grant
    Filed: March 15, 2002
    Date of Patent: November 4, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Shigeru Matsuyama, Hiroaki Asuma, Kazuhiko Yanagawa
  • Patent number: 6433852
    Abstract: To provide a transverse electric field liquid crystal display device which eliminates the leakage of light and suppresses the disturbance of the electric field between the electrodes, thus enabling an image display of high quality, a liquid crystal display device has a liquid crystal panel which provides at least two kinds of color filters FIL(R), FIL(G) . . . of different colors and a black matrix BM interposed between said respective color filters on one substrate SUB2, a group of electrodes PX, CT, CT1, CT2, SD2 . . . for selecting pixels formed on the other substrate SUB1, a liquid crystal layer LC made of a liquid crystal composition sandwiched between the substrates and having a dielectric anisotropy, a polarizing plate POL1, POL2 laminated on an outer surface of at least one of the substrates, and drive means which applies drive voltages for display to a group of the electrodes.
    Type: Grant
    Filed: December 3, 1999
    Date of Patent: August 13, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Hidehiro Sonoda, Masahito Ohe, Hiroaki Asuma, Shigeru Matsuyama
  • Publication number: 20020093617
    Abstract: For suppressing a brightness irregularity and contrast deterioration in a displaying screen of a liquid crystal display device which comprises a pair of substrates at least one of which is transparent, at least two kinds of color filters being formed on one of the pair of substrates, a black matrix being provided between the color filters, a group of electrodes being formed on either one of the pair of substrates, a layer of liquid crystal compounds sealed between the pair of substrates, due to noise electrical field appearing therein or unevenness of a cell gap between the pair of substrates, the present invention provides a columnar spacer having smaller resistivity than that of the liquid crystal compounds in a part of an area on the one of the pair of substrates which is hidden by the black matrix.
    Type: Application
    Filed: March 15, 2002
    Publication date: July 18, 2002
    Applicant: Hitachi Ltd.
    Inventors: Shigeru Matsuyama, Hiroaki Asuma, Kazuhiko Yanagawa
  • Patent number: 6411360
    Abstract: For suppressing a brightness irregularity and contrast deterioration in a displaying screen of a liquid crystal display device which comprises a pair of substrates at least one of which is transparent, at least two kinds of color filters being formed on one of the pair of substrates, a black matrix being provided between the color filters, a group of electrodes being formed on either one of the pair of substrates, a layer of liquid crystal compounds sealed between the pair of substrates, due to noise electrical field appearing therein or unevenness of a cell gap between the pair of substrates, the present invention provides a columnar spacer having smaller resistivity than that of the liquid crystal compounds in a part of an area on the one of the pair of substrates which is hidden by the black matrix.
    Type: Grant
    Filed: June 13, 2000
    Date of Patent: June 25, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Shigeru Matsuyama, Hiroaki Asuma, Kazuhiko Yanagawa
  • Publication number: 20020070912
    Abstract: A display region which is a collection of the pixel regions is divided into two separate display regions using an imaginary line extending along the x direction as a boundary. The scanning signal driving circuit which supplies the scanning signals to respective gate signal lines in one display region and the scanning signal driving circuit which supplies the scanning signals to respective gate signal lines in the other display region are separately formed. The drain signal lines at one display region are separated from the drain signal lines at the other display region. The video signal driving circuit which supplies the video signals to respective drain signal lines in one display region and the video signal driving circuit which supplies the video signals to respective drain signal lines in the other display region are separately formed. The display device with the little power consumption can thereby be obtained.
    Type: Application
    Filed: December 3, 2001
    Publication date: June 13, 2002
    Inventors: Hiroaki Asuma, Atsushi Hasegawa
  • Patent number: 6392732
    Abstract: An active matrix type liquid crystal display apparatus, including a pair of substrates and a liquid crystal layer interposed between said pair of substrates. One of the pair of substrates has plural scanning electrodes and plural signal electrodes arranged to cross the plural scanning electrodes. Pixels are formed at regions surrounded by the scanning electrodes and the signal electrodes. Respective ones of the pixels include an active element arranged at a vicinity of the crossing point of the scanning electrode and the signal electrode, a pixel electrode connected to the active element and a common electrode arranged in correspondence to the pixel electrode. Further, there is provided a colored filter and a shielding layer having a specific resistivity of less than 108 &OHgr;.cm.
    Type: Grant
    Filed: July 20, 2000
    Date of Patent: May 21, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Masahito Oh-e, Sukekazu Aratani, Shigeru Matsuyama, Hiroaki Asuma, Kiyoshige Kinugawa
  • Patent number: 6337728
    Abstract: A liquid crystal display device capable of preventing occurrence of display irregularity due to movement of spherical spacer materials. The liquid crystal display device includes a pixel electrode and counter electrode that are formed on a liquid crystal-side surface of one transparent substrate of respective transparent substrates disposed opposing each other with a liquid crystal being laid therebetween, wherein the transmissivity of light transmitting between this pixel electrode and the counter electrode is controlled by twisting of molecules of the liquid crystal as caused by an electric field generated between the pixel electrode and counter electrode. In the liquid crystal display device, spacer materials are provided between respective ones of said transparent substrates. These spacers are fixed and disposed on an insulating layer underlying an orientation film which is in contact with said liquid crystal on the one transparent substrate side.
    Type: Grant
    Filed: October 8, 1998
    Date of Patent: January 8, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Keiko Inoue, Shigeru Matsuyama, Setsuo Kobayashi, Hiroaki Asuma
  • Patent number: 6275279
    Abstract: In a liquid crystal display panel, the shrinkage of an end-scaling material for sticking a pair of substrates together is prevented or relaxed to restrain peeling of the end-sealing material from the substrates, thereby preventing any leakage of a liquid crystal and penetration of contaminants. A liquid crystal display device is assembled by bonding together a pair of substrates, which are opposed to each other across a predetermined gap and at least one of which has an electrode group formed over a surface opposed to the other substrate, with a sealing material along their peripheries excluding a liquid crystal filling port, and then sealing the liquid crystal filling port with an end-sealing material after the filling of the liquid crystal and hermetically sealing the liquid crystal in the gap between both substrates. In the liquid crystal display device, a resin which constitutes the end-sealing material contains particulates of average particle size of 0.1 &mgr;m to 3.
    Type: Grant
    Filed: December 1, 1999
    Date of Patent: August 14, 2001
    Assignee: Hitachi, LTD
    Inventors: Hiroaki Asuma, Shigeru Matsuyama, Tohru Sasaki, Noboru Kunimatsu, Masamitsu Furuie
  • Patent number: 6100956
    Abstract: In an active matrix type liquid crystal display apparatus, respective ones of the electrodes on a substrate are provided so that an electric field substantially parallel to the substrate can be supplied to a liquid crystal layer. Polarizers for changing the optical characteristics based on the alignment of the liquid crystal layer are provided, as well as a shielding layer formed in parallel to the image signal electrodes on the substrate. The specific resistivity of the shielding layer is less than 10.sup.8 .OMEGA..multidot.cm.
    Type: Grant
    Filed: August 24, 1998
    Date of Patent: August 8, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Masahito Oh-e, Sukekazu Aratani, Shigeru Matsuyama, Hiroaki Asuma, Kiyoshige Kinugawa
  • Patent number: 6040887
    Abstract: A liquid crystal display device comprising a black mask formed on one of a pair of substrates at least one of which is transparent, a group of electrodes formed on at least one of the pair of substrates, a liquid crystal layer comprising a liquid crystal composition substance having a dielectric anisotropy and held between the pair of substrates, an orientation control film formed between the liquid crystal layer and one of the substrates for orienting liquid crystal molecules of the liquid crystal composition substance in a predetermined direction, a polarizer laminated on at least one of the pair of substrates, and a driver for applying a drive voltage to the group of electrodes, wherein the group of electrodes has a structure that the electrodes are so arranged as to generate an electric field having a component predominantly in parallel with the interface between the orientation control film and the liquid crystal layer, the liquid crystal composition substance has a resistivity of not smaller than 10.
    Type: Grant
    Filed: October 28, 1998
    Date of Patent: March 21, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Shigeru Matsuyama, Hiroaki Asuma, Masato Shimura, Yoshifumi Tomita, Sukekazu Aratani
  • Patent number: 5831701
    Abstract: A liquid crystal display device comprising a black mask formed on one of a pair of substrates at least one of which is transparent, a group of electrodes formed on at least one of the pair of substrates, a liquid crystal layer comprising a liquid crystal composition substance having a dielectric anisotropy and held between the pair of substrates, an orientation control film formed between the liquid crystal layer and one of the substrates for orienting liquid crystal molecules of the liquid crystal composition substance in a predetermined direction, a polarizer laminated on at least one of the pair of substrates, and a driver for applying a drive voltage to the group of electrodes, wherein the group of electrodes has a structure that the electrodes are so arranged as to generate an electric field having a component predominantly in parallel with the interface between the orientation control film and the liquid crystal layer, the liquid crystal composition substance has a resistivity of not smaller than 10.
    Type: Grant
    Filed: June 6, 1996
    Date of Patent: November 3, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Shigeru Matsuyama, Hiroaki Asuma, Masato Shimura, Yoshifumi Tomita, Sukekazu Aratani
  • Patent number: 5805247
    Abstract: In an active matrix type liquid crystal display apparatus, respective ones of the electrodes on a substrate are provided so that an electric field substantially parallel to the substrate can be supplied to a liquid crystal layer. Polarizers for changing the optical characteristics based on the alignment of the liquid crystal layer are provided, as well as a shielding layer formed in parallel to the image signal electrodes on the substrate. The specific resistivity of the shielding layer is less than 10.sup.8 .OMEGA..multidot.cm.
    Type: Grant
    Filed: October 10, 1996
    Date of Patent: September 8, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Masahito Oh-e, Sukekazu Aratani, Shigeru Matsuyama, Hiroaki Asuma, Kiyoshige Kinugawa
  • Patent number: 5633739
    Abstract: A color liquid crystal display device comprising a color filter having a structure including a black matrix BM formed on a transparent substrate, a colored layer FIL colored into at least three primary colors and formed by thermal dye transfer technology, a protective area for protecting against dye diffusion filling the gaps between the colored patterns, a transparent protective overcoat PSV2 formed on the colored layer and a transparent conductive electrode ITO2 formed on the transparent protective overcoat. The protective area against dye diffusion is constituted of a not-colored part FIL(T) of a dye receiving layer, protective overcoats PSV2 and PSV3, or of a black matrix with a high heat resistance. Moreover, the protective film is made from a metal-containing organic silicon compound that can be hardened by light or heat.
    Type: Grant
    Filed: October 30, 1995
    Date of Patent: May 27, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Shigeru Matsuyama, Hiroaki Asuma
  • Patent number: 5541748
    Abstract: A liquid crystal display provided with a matrix of inverted-stagger thin-film transistors has a plurality of gate insulating films formed over gate lines and including one insulating film formed in contact with gate electrodes of the thin-film transistors and in self-alignment with gate lines in the picture display area of the liquid crystal display. The rest of the gate insulating films not crossing the gate electrodes and in contact with a semiconductor layer are patterned in conformity with drain electrodes (data lines), and a semiconductor layer and an insulating film not crossing the drain electrode and crossing the gate electrodes are patterned at the same time. The method has less steps than the conventional method, is capable of fabricating a liquid crystal display capable of displaying pictures in a high picture quality at a high yield rate.
    Type: Grant
    Filed: June 7, 1994
    Date of Patent: July 30, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Kikuo Ono, Junichi Ohwada, Hideaki Yamamoto, Hiroaki Asuma, Nobutake Konishi