Patents by Inventor Keiichiro Ashizawa

Keiichiro Ashizawa 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: 20090122249
    Abstract: The present invention is to provide the multi-domain system IPS (In-Plane Switching mode) liquid crystal display which has high contrast and does not have an improper image display. According to an aspect of the present invention, there is provided a black matrix formed between a pair of substrates and formed over a plurality of drain lines and gate lines, a plurality of spaces arranged under the black matrix, wherein a plurality of liquid crystal molecules lined to a boundary direction of the black matrix in “OFF” state, and having a first group and a second group in “ON” state, wherein a switching angle of the second group is opposite to a switching angle of the first group.
    Type: Application
    Filed: October 14, 2008
    Publication date: May 14, 2009
    Inventors: Kazuhiko Yanagawa, Keiichiro Ashizawa, Masahiro Ishii, Masayuki Hikiba
  • Publication number: 20090051864
    Abstract: A liquid crystal display device includes opposing first and second substrates with a liquid crystal therebetween, and plural spacers formed on second substrate. An uneven portion of a rectangular shape is formed in an area on the first substrate facing an end portion of the respective spacers, and the end portion of the respective spacers and the uneven portion contact mutually, and a long side of the uneven portion is longer than one side of the end portion of the respective spacers, and a short side of the uneven portion is shorter than another side of the end portion of the respective spacers.
    Type: Application
    Filed: October 3, 2008
    Publication date: February 26, 2009
    Inventors: Kazuhiko Yanagawa, Keiichiro Ashizawa, Masahiro Ishii, Masayuki Hikiba
  • Publication number: 20090040438
    Abstract: A liquid crystal display apparatus includes a liquid crystal panel having polarizers, and a back light having a light source for illumination of the liquid crystal panel which has a characteristic of spectral transmittance required to satisfy the following equation, x>y>z, when a medium tone display voltage varies in a range between a minimum and maximum voltage for a Blue pixel, where “x” is a value of the transmittance in the panel at a wavelength corresponding to a longest wavelength in a range of wavelengths designated for blue light, “y” is a value of the transmittance in the panel at a wavelength corresponding to a maximum value of the intensity in a range of wavelengths designated for green light, and “z” is a value of the transmittance in the panel at a wavelength corresponding to a maximum value of the intensity in a range of wavelengths designated for red light.
    Type: Application
    Filed: October 2, 2008
    Publication date: February 12, 2009
    Inventors: Yuka Utsumi, Katsumi Kondo, Ikuo Hiyama, Osamu Itoh, Masahito Ohe, Kazuhiko Yanagawa, Keiichiro Ashizawa
  • Publication number: 20080303998
    Abstract: A liquid crystal display device includes a pair of substrates with a liquid crystal layer therebetween with a plurality of scanning signal lines and of video signal lines being formed on a first substrate. The scanning and video signal lines are arranged in a shape of a grid, and a pixel region is defined as a region surrounded by the scanning and video signal lines. A black matrix is formed on a second substrate, is arranged in a position overlapped on the scanning and video signal lines, and has an opening portion in each pixel region. A plurality of first electrodes are provided on the first substrate, and a plurality of second electrodes are provided on the second substrate, wherein at least one of first electrodes and at least one of the second electrodes are arranged in a position overlapped with the opening portion.
    Type: Application
    Filed: March 12, 2008
    Publication date: December 11, 2008
    Inventors: Masuyuki OHTA, Kazuhiko Yanagawa, Kazuhiro Ogawa, Keiichiro Ashizawa, Masahiro Yanai, Nobutake Konishi, Katsumi Kondo, Masahito Ohe, Sukekazu Aratani, Hagen Klausmann
  • Publication number: 20080297714
    Abstract: A display device includes first and second substrates with a liquid crystal layer therebetween, video signal lines and scan lines on one of the substrates, and display electrodes connected to a video signal line through an active device. Pixel areas are defined by the video signal and scan signal lines, and each pixel area has the display electrode, a reference electrode and the active device. Display electrodes are arranged on the first substrate and reference electrodes are arranged the second substrate. A part of the reference electrodes have a plurality layers and is conductive. A sealing material is formed between the substrates and along a periphery thereof and include conductive beads. A connecting terminal is formed from an edge of the first substrate to under the sealing material, and is connected electrically to the reference electrodes thorough the sealing material.
    Type: Application
    Filed: August 4, 2008
    Publication date: December 4, 2008
    Inventors: Kazuhiko Yanagawa, Masuyuki Ohta, Kazuhiro Ogawa, Keiichiro Ashizawa, Masahiro Yanai, Nobutake Konishi
  • Patent number: 7460201
    Abstract: A display device includes first and second substrates, video signal lines, gate signal lines, and counter voltage signal lines formed on the first substrate. Pixel electrodes, counter electrodes which are connected to the counter voltage signal line, and thin film transistors are formed on the first substrate. Pixels are formed wherein each pixel includes a pixel electrode, a counter electrode and a thin film transistor. The thin film transistor includes a first semiconductor layer, a drain electrode electrically connected to the video signal line, and a source electrode electrically connected to the pixel electrode. The pixel electrode has at least a first side portion which extends in parallel to the video signal line and at least a second side portion which does not extend in parallel to the video signal line and the gate signal line.
    Type: Grant
    Filed: July 18, 2007
    Date of Patent: December 2, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Keiichiro Ashizawa, Masayuki Hikiba, Masuyuki Ohta
  • Patent number: 7453541
    Abstract: The present invention is to provide the multi-domain system IPS (In-Plane Switching mode) liquid crystal display which has high contrast and does not have an improper image display. According to an aspect of the present invention, there is provided a black matrix formed between a pair of substrates and formed over a plurality of drain lines and gate lines, a plurality of spaces arranged under the black matrix, wherein a plurality of liquid crystal molecules lined to a boundary direction of the black matrix in “OFF” state, and having a first group and a second group in “ON” state, wherein a switching angle of the second group is opposite to a switching angle of the first group.
    Type: Grant
    Filed: May 2, 2007
    Date of Patent: November 18, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Kazuhiko Yanagawa, Keiichiro Ashizawa, Masahiro Ishii, Masayuki Hikiba
  • Publication number: 20080259267
    Abstract: A liquid crystal display device with a pair of substrates which are arranged to face each other with liquid crystal therebetween, columnar spacers having the substantially equal height formed on a liquid-crystal-side surface of one substrate, and the columnar spacers include the columnar spacer which is contact with a liquid-crystal-side surface of another substrate and the columnar spacer which is not contact with the liquid-crystal-side surface of another substrate.
    Type: Application
    Filed: May 5, 2008
    Publication date: October 23, 2008
    Inventors: Keiichiro Ashizawa, Mitsuo Nakatani, Hiroaki Miwa, Takao Tanaka, Sadafumi Hirai, Shinichi Kawabe, Makoto Sasaki, Kazuyuki Ito, Masahiro Ieda
  • Patent number: 7433012
    Abstract: A liquid crystal display apparatus includes a liquid crystal panel including a pair of polarizers, and a back light provided at a back side of said liquid crystal panel. The liquid crystal panel is an active matrix type liquid crystal panel enabling display and has a characteristic of spectral transmittance required to satisfy the following equation, ×>y, when a drive voltage is applied thereto so as to vary from a dark state to a light state, in which “x” is a value of the transmittance in the liquid crystal panel at a wavelength which corresponds to one of 490 nm and 500 nm, and “y” is a value of the transmittance in the liquid crystal panel at a wavelength which corresponds to 545 nm.
    Type: Grant
    Filed: December 13, 2005
    Date of Patent: October 7, 2008
    Inventors: Yuka Utsumi, Katsumi Kondo, Ikuo Hiyama, Osamu Itoh, Masahito Ohe, Kazuhiko Yanagawa, Keiichiro Ashizawa
  • Patent number: 7408609
    Abstract: An active matrix liquid crystal display device includes a pair of substrates and a liquid crystal layer, a video signal lines and scan signal lines delimiting pixel areas having pixel electrodes and display electrodes, reference electrodes and active devices. The display electrodes are arranged on one of the substrates, and the reference electrodes are arranged on another of the substrates. A part of the reference electrodes have a first layer formed in the substrate side and a second layer formed in the liquid crystal layer side. Each of the display electrodes and the reference electrodes has a slit, the slit of the display electrodes and the slit of the reference electrodes being shifted with respect to one another in plan view.
    Type: Grant
    Filed: September 24, 2007
    Date of Patent: August 5, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Kazuhiko Yanagawa, Masuyuki Ohta, Kazuhiro Ogawa, Keiichiro Ashizawa, Masahiro Yanai, Nobutake Konishi
  • Patent number: 7385666
    Abstract: A liquid crystal display device with a pair of substrates which are arranged to face each other with liquid crystal therebetween, columnar spacers having the substantially equal height formed on a liquid-crystal-side surface of one substrate, and the columnar spacers include the columnar spacer which is contact with a liquid-crystal-side surface of another substrate and the columnar spacer which is not contact with the liquid-crystal-side surface of another substrate.
    Type: Grant
    Filed: October 21, 2004
    Date of Patent: June 10, 2008
    Assignee: Hitachi Displays, Ltd.
    Inventors: Keiichiro Ashizawa, Mitsuo Nakatani, Hiroaki Miwa, Takao Tanaka, Sadafumi Hirai, Shinichi Kawabe, Makoto Sasaki, Kazuyuki Ito, Masahiro Ieda
  • Patent number: 7345729
    Abstract: A liquid crystal display device includes a pair of substrates with a liquid crystal layer therebetween, a plurality of scanning signal lines and a plurality of video signal lines formed on one of said pair of substrates, a plurality of first electrodes on the one of said pair of substrates and a plurality of second electrodes on the one of said pair of substrates to drive the liquid crystal by a voltage difference with respect to the first electrode. The first electrodes have a bent form, and the second electrodes have a rectangular form.
    Type: Grant
    Filed: June 15, 2006
    Date of Patent: March 18, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Masuyuki Ohta, Kazuhiko Yanagawa, Kazuhiro Ogawa, Keiichiro Ashizawa, Masahiro Yanai, Nobutake Konishi, Katsumi Kondo, Masahito Ohe, Sukekazu Aratani, Hagen Klausmann
  • Publication number: 20080024711
    Abstract: An active matrix liquid crystal display device includes a pair of substrates and a liquid crystal layer, a video signal lines and scan signal lines delimiting pixel areas having pixel electrodes and display electrodes, reference electrodes and active devices. The display electrodes are arranged on one of the substrates, and the reference electrodes are arranged on another of the substrates. A part of the reference electrodes have a first layer formed in the substrate side and a second layer formed in the liquid crystal layer side. Each of the display electrodes and the reference electrodes has a slit, the slit of the display electrodes and the slit of the reference electrodes being shifted with respect to one another in plan view.
    Type: Application
    Filed: September 24, 2007
    Publication date: January 31, 2008
    Inventors: Kazuhiko Yanagawa, Masuyuki Ohta, Kazuhiro Ogawa, Keiichiro Ashizawa, Masahiro Yanai, Nobutake Konishi
  • Publication number: 20080013031
    Abstract: A display device includes first and second substrates, video signal lines, gate signal lines, and counter voltage signal lines formed on the first substrate. Pixel electrodes, counter electrodes which are connected to the counter voltage signal line, and thin film transistors are formed on the first substrate. Pixels are formed wherein each pixel includes a pixel electrode, a counter electrode and a thin film transistor. The thin film transistor includes a first semiconductor layer, a drain electrode electrically connected to the video signal line, and a source electrode electrically connected to the pixel electrode. The pixel electrode has at least a first side portion which extends in parallel to the video signal line and at least a second side portion which does not extend in parallel to the video signal line and the gate signal line.
    Type: Application
    Filed: July 18, 2007
    Publication date: January 17, 2008
    Inventors: Keiichiro ASHIZAWA, Masayuki Hikiba, Masuyuki Ohta
  • Patent number: 7298449
    Abstract: A first transparent substrate and a second transparent substrate having such a plurality of protrusions on the liquid crystal layer side as to contact with the first transparent substrate are so fixed by means of a sealant that they bend convexly to the liquid crystal layer. Thus, it is possible to suppress the mura defect of a panel, which might otherwise be caused by the heat radiation from a back light when a liquid crystal display apparatus is driven.
    Type: Grant
    Filed: August 10, 2004
    Date of Patent: November 20, 2007
    Assignee: Hitachi Displays, Ltd.
    Inventors: Makoto Tatemura, Hideyuki Honoki, Hiroko Hayata, Masanori Yuki, Keiichiro Ashizawa
  • Patent number: 7289182
    Abstract: An active matrix liquid crystal display device includes substrates, a liquid crystal layer therebetween, video signal lines and scan signal lines formed on one of the substrates, and pixel electrodes connected to one of the video signal lines through an active device. Pixel areas, which are defined by the video signal lines and the scan signal lines which are formed in the shape of a matrix, have display electrodes, reference electrodes and the active device arranged therein. The display electrodes are arranged on one of the substrates, and the reference electrodes are arranged on another of the substrates, and each of the display electrodes and the reference electrodes has a slit. The slit of the display electrodes and the slit of the reference electrodes are shifted with respect to one another in plan view.
    Type: Grant
    Filed: August 29, 2006
    Date of Patent: October 30, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Kazuhiko Yanagawa, Masuyuki Ohta, Kazuhiro Ogawa, Keiichiro Ashizawa, Masahiro Yanai, Nobutake Konishi
  • Publication number: 20070206145
    Abstract: The present invention is to provide the multi-domain system IPS (In-Plane Switching mode) liquid crystal display which has high contrast and does not have an improper image display. According to an aspect of the present invention, there is provided a black matrix formed between a pair of substrates and formed over a plurality of drain lines and gate lines, a plurality of spaces arranged under the black matrix, wherein a plurality of liquid crystal molecules lined to a boundary direction of the black matrix in “OFF” state, and having a first group and a second group in “ON” state, wherein a switching angle of the second group is opposite to a switching angle of the first group.
    Type: Application
    Filed: May 2, 2007
    Publication date: September 6, 2007
    Inventors: Kazuhiko Yanagawa, Keiichiro Ashizawa, Masahiro Ishii, Masayuki Hikiba
  • Patent number: 7251007
    Abstract: A display device includes a first substrate having formed thereon a plurality of video signal lines and a plurality of gate signal lines, a plurality of pixel electrodes, a plurality of thin film transistors, and a plurality of pixels. Each pixel includes a pixel electrode of the plurality of pixel electrodes and a thin film transistor of the plurality of thin film transistors. The thin film transistor includes a semiconductor layer, a drain electrode electrically connected to a drain signal line, and a source electrode electrically connected to the pixel electrode. The semiconductor layer has an outline so that a nearest portion to a center of the pixel is positioned under the source electrode in plan view.
    Type: Grant
    Filed: June 16, 2005
    Date of Patent: July 31, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Keiichiro Ashizawa, Masayuki Hikiba, Masuyuki Ohta
  • Patent number: 7248325
    Abstract: The present invention is to provide the multi-domain system IPS (In-Plane Switching mode) liquid crystal display which has high contrast and does not have an improper image display. According to an aspect of the present invention, there is provided a black matrix formed between a pair of substrates and formed over a plurality of drain lines and gate lines, a plurality of spaces arranged under the black matrix, wherein a plurality of liquid crystal molecules lined to a boundary direction of the black matrix in “OFF” state, and having a first group and a second group in “ON” state, wherein a switching angle of the second group is opposite to a switching angle of the first group.
    Type: Grant
    Filed: March 15, 2005
    Date of Patent: July 24, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Kazuhiko Yanagawa, Keiichiro Ashizawa, Masahiro Ishii, Masayuki Hikiba
  • Patent number: 7209211
    Abstract: A liquid crystal display apparatus having a liquid crystal panel including a pair of substrates, a plurality of electrodes formed on at least one of the pair of substrates and a liquid crystal layer sandwiched between the pair of substrates, and a light source provided on one surface of the liquid crystal panel. An electric field in the liquid crystal layer produced by the plurality of electrodes is predominantly in parallel with surfaces of the pair of substrates. The light source has a luminous characteristic with a first chromaticity and the liquid crystal panel has a characteristic of spectral transmittance with a second chromaticity different from the first chromaticity so as to compensate for the color of the light source.
    Type: Grant
    Filed: July 30, 2003
    Date of Patent: April 24, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Yuka Utsumi, Katsumi Kondo, Ikuo Hiyama, Osamu Itoh, Masahito Ohe, Kazuhiko Yanagawa, Keiichiro Ashizawa