Patents by Inventor Junichi Hirakata

Junichi Hirakata 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: 20050195348
    Abstract: A novel optical compensation film is disclosed. The optical compensation film has Re/Rth(450 nm), a ratio of Re to Rth measured at 450 nm, 0.4 to 0.95 times as large as Re/Rth(550 nm) at 550 nm, and having Re/Rth(650 nm) at 650 nm 1.05 to 1.9 times as large as Re/Rth(550 nm) at 550 nm. In the formulae, Re is in-plane retardation defined as Re={(nx?ny)×d1}; Rth is depth retardation defined as Rth=[{(nx+ny)/2?nz}×d1]; d1(nm) is a thickness of the film, nx, ny and nz are respectively mean refractive indices in the directions of x-axis, y-axis and z-axis orthogonal to each other; nx and ny are in-plane main mean refractive indices in parallel with the surface of said optical compensation film (where, ny<nx); and nz is a depth main mean refractive index.
    Type: Application
    Filed: February 9, 2005
    Publication date: September 8, 2005
    Applicant: Fuji Photo Film Co., Ltd.
    Inventors: Yukito Saitoh, Junichi Hirakata
  • Publication number: 20050162592
    Abstract: To provide a liquid crystal display, particularly TN type liquid crystal display capable of remarkably improving brightness inversion resistance at a high contrast with a simple configuration and an optical compensation film which realizes the aforementioned properties, the liquid crystal display includes a pair of polarizing plates, each of the polarizing plates being disposed on an outer side of a liquid crystal layer having a twisted structure, the liquid crystal layer being disposed between substrates facing to each other, at least one of the substrates having an electrode, each of the polarizing plates including a polarizing film, a protective film, and an optical compensation film, wherein the optical compensation film includes a compound having a discotic structure unit, and the compound having a discotic structure unit is aligned such that the average alignment direction of the molecular major axis of the discotic structure unit at each side of the upper and lower optical compensation films facing to
    Type: Application
    Filed: March 24, 2005
    Publication date: July 28, 2005
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventors: Junichi Hirakata, Kentaro Toyooka, Hiroyuki Mori
  • Publication number: 20050157225
    Abstract: A novel liquid crystal display is disclosed. The display comprises a pair of substrates disposed facing each other and at least one of which has an electrode, a liquid-crystal layer being sandwiched in between the pair of substrates and comprising liquid-crystal molecules aligned along with a first alignment axis and a second alignment axis respectively formed on facing surfaces of the first and second substrates, a pair of polarizing plates disposed sandwiching the liquid-crystal layer, and at least an optically anisotropic layer disposed between the liquid-crystal layer and either of the polarizing plates, and comprising at least one liquid crystal compound which is aligned along with a third alignment axis and is fixed in the alignment state.
    Type: Application
    Filed: January 14, 2005
    Publication date: July 21, 2005
    Applicant: Fuji Photo Film Co., Ltd.
    Inventors: Kentaro Toyooka, Yusuke Ohashi, Junichi Hirakata
  • Patent number: 6903716
    Abstract: In a display device, a first drive circuit supplies one and another first signals to plural adjacent scanning signal lines during first and second time intervals in a frame period, respectively. During the first time interval, a second drive circuit generates a second voltage corresponding to video data and supplies the second voltage to pixels associated with the adjacent scanning signal lines supplied with the first signal, and during the second time interval, the second drive circuit generates and supplies a second voltage to ones of the pixels associated with the adjacent scanning signal lines supplied with the first signal such that the pixels associated with the adjacent scanning signal lines supplied with the first signal produce luminance lower than that produced during the first time interval.
    Type: Grant
    Filed: March 7, 2003
    Date of Patent: June 7, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Kazuyoshi Kawabe, Junichi Hirakata
  • Publication number: 20050083470
    Abstract: A liquid crystal display device having first and second substrates with a liquid crystal layer therebetween, a plurality of gate signal lines and a plurality of drain signal lines, a plurality of counter voltage signal lines, a plurality of pixel regions defined by neighboring gate signal lines and drain signal lines, a counter electrode and a pixel electrode enabling formation of an electric field, and an orientation film being formed on the first substrate. The pixel electrode has a plurality of slits overlaps the counter electrode with an insulating layer therebetween. A pair of edges of the counter electrode and pixel electrode extend in parallel to the gate signal line and another pair of edges of the counter electrode and the pixel electrode extend in parallel to the drain line.
    Type: Application
    Filed: December 6, 2004
    Publication date: April 21, 2005
    Inventors: Kikuo Ono, Makoto Yoneya, Tsunenori Yamamoto, Junichi Hirakata, Yoshiaki Nakayoshi
  • Publication number: 20050083471
    Abstract: A liquid crystal display device having first and second substrates with a liquid crystal layer therebetween, a plurality of gate signal lines and a plurality of drain signal lines, a plurality of pixel regions defined by neighboring gate signal lines and drain signal lines, and a pixel electrode in each pixel region. The drain signal line has a metal layer and another layer formed by a transparent conductor, and the another layer is electrically connected to the metal layer. The pixel electrode is made of a transparent conductor, and a transparent conductor of the pixel electrode and the transparent conductor of the drain signal line are of the same material.
    Type: Application
    Filed: December 6, 2004
    Publication date: April 21, 2005
    Inventors: Kikuo Ono, Makoto Yoneya, Tsunenori Yamamoto, Junichi Hirakata, Yoshiaki Nakayoshi
  • Publication number: 20050078261
    Abstract: A liquid crystal display device having first and second substrates with a liquid crystal layer therebetween, a plurality of gate signal lines and a plurality of drain signal lines, a plurality of counter voltage signal lines, a plurality of pixel regions defined by neighboring gate signal lines and drain signal lines. and a counter electrode and a pixel electrode formed on the first substrate in each pixel region so as to enable an electric field to be formed therebetween. The counter electrode is of planar shape and made of a transparent conductor. The counter voltage signal line is made of metal and has a branch in each pixel region with the counter electrode being directly connected to the branch.
    Type: Application
    Filed: December 3, 2004
    Publication date: April 14, 2005
    Inventors: Kikuo Ono, Makoto Yoneya, Tsunenori Yamamoto, Junichi Hirakata, Yoshiaki Nakayoshi
  • Publication number: 20050078262
    Abstract: A liquid crystal display device having a first transparent insulating substrate, a second transparent insulating substrate, a liquid crystal layer having liquid crystal molecules interposed between the first and second substrates, a plurality of gate bus lines and a plurality of data bus lines formed on the first substrate, wherein an area formed by two gate bus lines intersecting two data bus lines substantially defines a unit pixel. A pixel electrode made from a transparent conductor material is arranged in each unit pixel and has a plurality of upper slits parallelly arranged at a first tilt angle and a plurality of lower slits parallelly arranged at a second tilt angle and the upper slits and the lower slits are arranged in the unit pixel as an mirror image of each other and upper slits not connected to any of the lower slits.
    Type: Application
    Filed: December 6, 2004
    Publication date: April 14, 2005
    Inventors: Kikuo Ono, Makoto Yoneya, Tsunenori Yamamoto, Junichi Hirakata, Yoshiaki Nakayoshi
  • Publication number: 20050078260
    Abstract: A liquid crystal display device having first and second substrates with a liquid crystal layer therebetween, a plurality of gate signal lines made of metal and a plurality of drain signal lines made of metal, a plurality of counter voltage signal lines, a plurality of pixel regions defined by neighboring gate signal lines and drain signal lines and a pixel electrode formed on first substrate in each pixel region. The pixel electrode and the counter voltage signal lines have an overlapping region, and an edge of the pixel electrode which extends in parallel to the drain signal line shifts to inside of the pixel region at the overlapping region as compared to the edge of the pixel electrode at a non-overlapping region.
    Type: Application
    Filed: December 3, 2004
    Publication date: April 14, 2005
    Inventors: Kikuo Ono, Makoto Yoneya, Tsunenori Yamamoto, Junichi Hirakata, Yoshiaki Nakayoshi
  • Publication number: 20050030461
    Abstract: A liquid crystal display device having first and second substrates with a liquid crystal layer therebetween, a plurality of gate signal lines and a plurality of drain signal lines, a plurality of counter voltage signal lines, a plurality of pixel regions defined by neighboring gate signal lines and drain signal lines and a counter electrode and a pixel electrode being formed on the first substrate in each pixel region and enabling forming of an electric field therebetween. The counter electrode is of planar shape and, the pixel electrode is of planar shape with plurality of slits and is overlapped with the counter electrode with an insulating layer provided therebetween. Both the counter electrode and pixel electrode are made of a transparent conductor. The counter voltage signal line is made of metal and extends in center region in each pixel region and is directly connected to the counter electrode.
    Type: Application
    Filed: September 14, 2004
    Publication date: February 10, 2005
    Inventors: Kikuo Ono, Makoto Yoneya, Tsunenori Yamamoto, Junichi Hirakata, Yoshiaki Nakayoshi
  • Patent number: 6798480
    Abstract: To improve optical transmission efficiency without reducing optical reflection efficiency.
    Type: Grant
    Filed: November 20, 2001
    Date of Patent: September 28, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Kikuo Ono, Junichi Hirakata, Takahiro Ochiai, Ryuutaro Oke
  • Publication number: 20040051692
    Abstract: A liquid crystal display device includes a liquid crystal display panel and a lighting device. The lighting device is supplied with alternately a first current during a period t1, and a second current during a second period t2 such that electric power E1 is lower than electric power E2. E1 is defined as (t1×ip−p(1)×Vp−p(1))/2+(t2×ip−p(2)×Vp−p(2))/2, where ip−p(1)=a peak-to-peak value of the first current, Vp−p(1)=a peak-to-peak value of a voltage across the light source during the period t1, ip−p(2)=a peak-to-peak value of the second current, and Vp−p(2)=a peak-to-peak value of a voltage across the light source during the period t2. E2 is defined as (t1+t2)×Ioff×Voff, where Ioff and Voff are effective values of the current and voltage of the light source, respectively.
    Type: Application
    Filed: August 8, 2003
    Publication date: March 18, 2004
    Applicants: Hitachi, Ltd., Hitachi Device Engineering Co., Ltd.
    Inventors: Junichi Hirakata, Kikuo Ono, Akira Shingai
  • Patent number: 6636190
    Abstract: A liquid crystal display device includes a liquid crystal display panel and a lighting device. The lighting device is supplied with alternately a first current during a period t1 and a second current during a second period t2 such that electric power E1 is lower than electric power E2. E1 is defined as (t1×ip-p(1)×Vp-p(1))/2+(t2×ip-p(2)×Vp-p(2))/2, where ip-p(1)=a peak-to-peak value of the first current, Vp-p(1)=a peak-to-peak value of a voltage across the light source during the period t1, ip-p(2)=a peak-to-peak value of the second current, and Vp-p(2)=a peak-to-peak value of a voltage across the light source during the period t2. E2 is defined as (t1+t2)×Ieff×Veff, where Ieff and Veff are effective values of the current and voltage of the light source, respectively.
    Type: Grant
    Filed: August 23, 2001
    Date of Patent: October 21, 2003
    Assignees: Hitachi, Ltd., Hitachi Device Engineering Co., Ltd.
    Inventors: Junichi Hirakata, Kikuo Ono, Akira Shingai
  • Publication number: 20030179221
    Abstract: In a hold-type display device such as a liquid crystal display device, a so-called blurring which appears on a profile of a displayed animated image or the like can be suppressed without damaging the brightness of the display image. According to the present invention, an image based on video data to be inputted to a display device is displayed for every frame period and, thereafter, the image is masked with a blanking image. Here, a ratio between an image display period of the video data and a blanking image display period in one frame period is adjusted based on the number of selection of pixel rows in a pixel array in response to a scanning clock for respective periods, frequency of the scanning clock, shortening of a horizontal period of display signal inputting to every pixel row with respect to a horizontal scanning period of the video data whereby the display image can be efficiently cancelled using the blanking image while ensuring the image display brightness of the video data.
    Type: Application
    Filed: March 20, 2003
    Publication date: September 25, 2003
    Inventors: Hiroyuki Nitta, Tsutomu Furuhashi, Junichi Hirakata, Yoshinori Tanaka, Kazuyoshi Kawabe
  • Publication number: 20030169247
    Abstract: In a display device, a first drive circuit supplies one and another first signals to plural adjacent scanning signal lines during first and second time intervals in a frame period, respectively. During the first time interval, a second drive circuit generates a second voltage corresponding to video data and supplies the second voltage to pixels associated with the adjacent scanning signal lines supplied with the first signal, and during the second time interval, the second drive circuit generates and supplies a second voltage to ones of the pixels associated with the adjacent scanning signal lines supplied with the first signal such that the pixels associated with the adjacent scanning signal lines supplied with the first signal produce luminance lower than that produced during the first time interval.
    Type: Application
    Filed: March 7, 2003
    Publication date: September 11, 2003
    Inventors: Kazuyoshi Kawabe, Junichi Hirakata
  • Publication number: 20030058229
    Abstract: A matrix-type display device includes a data generating circuit 102 for multiple scans for inserting blanking data to image data for one frame period of an image, and a timing controlling circuit 103 for multiple scans for generating clocks used by a gate line drive circuit 104 for scanning lines of a display element array 107 such that the image data and the blanking data can be displayed in one frame period. Here, the gate line drive circuit 104 simultaneously scans multiple lines adjacent to each other as a bundle. According to this configuration, the larger and more complicated construction can be suppressed, which can also suppress the image deterioration due to blurred moving picture.
    Type: Application
    Filed: July 23, 2002
    Publication date: March 27, 2003
    Inventors: Kazuyoshi Kawabe, Junichi Hirakata
  • Publication number: 20030043097
    Abstract: A liquid crystal display device having superior moving-image display characteristics are provided. In the liquid crystal display device, the timing of application of grayscale voltage to liquid crystal cells at the top end of its screen with respect to the timing of application of grayscale voltage to liquid crystal cells in the center of the screen and the timing of application of grayscale voltage to liquid crystal cells at the bottom end of the screen with respect to the timing of application of grayscale voltage to the liquid crystal cells in the center of the screen are made approximately coincident with each other or are deviated from each other by approximately one scanning-line selection period, and a liquid crystal panel is illuminated by a backlight which is intermittently lit in synchronism with vertical synchronizing signals.
    Type: Application
    Filed: May 15, 2002
    Publication date: March 6, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Akira Shingai, Junichi Hirakata
  • Patent number: 6404475
    Abstract: A liquid crystal display device suitable for generating an electric field sufficiently between the pixel electrode and the counter electrode to control the orientations of the liquid crystal molecules lying therebetween has a simple structure. A liquid crystal display device has a pair of substrates superposed on one another between which a liquid crystal layer is sealed, at least one video signal line and at least one pixel being formed on a surface of one of the pair of substrates confronting the liquid crystal layer. The pixel has at least one pixel electrode and at least two counter electrodes spaced from each other, and one of the counter electrodes is disposed adjacent to the one video signal line. The one video signal line and the one of the counter electrodes are spaced from one another by at least two insulating regions disposed along the surface, and one of the insulating regions comprises a material having a higher permittivity than that of the other regions.
    Type: Grant
    Filed: August 11, 1999
    Date of Patent: June 11, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Yoshiaki Nakayoshi, Kikuo Ono, Junichi Hirakata, Masahiro Ishii, Masuyuki Ohta, Nobuyuki Suzuki
  • Publication number: 20020067332
    Abstract: In a liquid crystal display device having a backlight, the backlight has a first state which outputs a first amount of light and a second state which generates a second amount of light and the time for the first state and the time for the second state are controlled. Due to such a constitution, the liquid crystal display device can display clear motion picture images in spite of a simple constitution thereof. Further, the liquid crystal display device can display clear and bright motion picture images.
    Type: Application
    Filed: November 15, 2001
    Publication date: June 6, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Junichi Hirakata, Kikuo Ono, Akira Shingai
  • Publication number: 20020057238
    Abstract: The present invention includes a panel on which a plurality of pixels are located, a light-source for visualizing an image displayed on the plurality of pixels, a controlling circuit for controlling the light-source, and an image-signal tone characteristic controlling circuit. Moreover, the light-source controlling circuit has a function of repeating a period. Here, the period includes a 1st time-period during which an electric current having a 1st intensity is fed to the light-source, and a 2nd time-period during which an electric current having a 2nd intensity differing from the 1st intensity is fed to the light-source. The light-source controlling circuit controls the 1st time-period and the 2nd time-period in accordance with display information. Also, in accordance with the display information as well, the tone characteristic controlling circuit is controlled so that the excellent contrast will be always available.
    Type: Application
    Filed: June 26, 2001
    Publication date: May 16, 2002
    Inventors: Hiroyuki Nitta, Takeshi Maeda, Kazuyoshi Kawabe, Junichi Hirakata