Patents by Inventor Hirobumi Koshi

Hirobumi Koshi 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: 7098881
    Abstract: A fast-write, high picture-quality LCD (Liquid Crystal Display) compatible with a high-resolution, large-sized liquid crystal panel. An output amplifier circuit of a liquid crystal driver circuit includes an amplifier configuration, which functions as an amplifier that amplifies the predetermined gray-scale voltage for output and as an amplifier that buffers the predetermined gray-scale voltage and outputs with no amplification, and a circuit for switching the above two types of amplifiers. In each horizontal period, a liquid crystal panel is driven by the amplified output for a predetermined period and by the buffered output for the rest of the period. A precharge control circuit is provided to check whether the gray-scale voltage is to be amplified depending upon display data.
    Type: Grant
    Filed: October 20, 2003
    Date of Patent: August 29, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Hiroyuki Nitta, Kazuyoshi Kawabe, Satoru Tsunekawa, Hirobumi Koshi
  • Patent number: 6801178
    Abstract: A liquid crystal driving device for controlling a liquid crystal panel and a liquid crystal display apparatus. Reference voltages are generated in a data driver from input reference voltages, and reference voltages are selected in accordance with the settings of gray scale control registers thereby to control the gray scale voltages.
    Type: Grant
    Filed: July 25, 2001
    Date of Patent: October 5, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Hiroyuki Nitta, Tsutomu Furuhashi, Makoto Kimura, Hirobumi Koshi, Takeshi Maeda
  • Publication number: 20040080522
    Abstract: A fast-write, high picture-quality LCD (Liquid Crystal Display) compatible with a high-resolution, large-sized liquid crystal panel. An output amplifier circuit of a liquid crystal driver circuit includes an amplifier configuration, which functions as an amplifier that amplifies the predetermined gray-scale voltage for output and as an amplifier that buffers the predetermined gray-scale voltage and outputs with no amplification, and a circuit for switching the above two types of amplifiers. In each horizontal period, a liquid crystal panel is driven by the amplified output for a predetermined period and by the buffered output for the rest of the period. A pre-charge control circuit is provided to check whether the gray-scale voltage is to be amplified depending upon display data.
    Type: Application
    Filed: October 20, 2003
    Publication date: April 29, 2004
    Inventors: Hiroyuki Nitta, Kazuyoshi Kawabe, Satoru Tsunekawa, Hirobumi Koshi
  • Patent number: 6661402
    Abstract: A fast-write, high picture-quality LCD (Liquid Crystal Display) compatible with a high-resolution, large-sized liquid crystal panel. An output amplifier circuit of a liquid crystal driver circuit includes an amplifier configuration, which functions as an amplifier that amplifies the predetermined gray-scale voltage for output and as an amplifier that buffers the predetermined gray-scale voltage and outputs with no amplification, and a circuit for switching the above two types of amplifiers. In each horizontal period, a liquid crystal panel is driven by the amplified output for a predetermined period and by the buffered output for the rest of the period. A pre-charge control circuit is provided to check whether the gray-scale voltage is to be amplified depending upon display data.
    Type: Grant
    Filed: October 30, 2000
    Date of Patent: December 9, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Hiroyuki Nitta, Kazuyoshi Kawabe, Satoru Tsunekawa, Hirobumi Koshi
  • Patent number: 6625207
    Abstract: In a low power consumption data transmission circuit and method, and a liquid crystal display apparatus using the same, 24-bit display data is transmitted from a transceiver circuit to a receiver circuit through a transmission line so that the display data is displayed on a liquid crystal panel. The transceiver circuit has a holding circuit including an 8-stage shift register. The transceiver circuit outputs 24-bit data to the transmission line by use of first and second output circuits when data different from data held in the holding circuit is to be transmitted from the transmission line and outputs data indicative of a hold position in the holding circuit from the second output circuit when the same data as that held in the holding circuit is to be transmitted from the transmission line.
    Type: Grant
    Filed: September 30, 1999
    Date of Patent: September 23, 2003
    Assignees: Hitachi, Ltd., Hitachi Video & Information System, Inc.
    Inventors: Hiroyuki Nitta, Satoru Tsunekawa, Hirobumi Koshi, Atsuhiro Higa
  • Patent number: 6603468
    Abstract: A liquid crystal display device includes a liquid crystal panel; a plurality of data drivers for applying, to the pixel elements, graduation voltages corresponding to the display data; a gate driver for selecting a pixel element to which a graduation voltage is to be applied; and a liquid crystal control circuit for controlling the data drivers on the basis of a transfer clock. Each data driver includes a reproducing circuit for reproducing the transfer clock input to the data driver such that the deviations between the duties of the display data and the transfer clock input to the data driver and the duties of the display data and the transfer clock output from the data driver become small, and for generating a latch clock, and a latch circuit for latching the display data input to the data driver.
    Type: Grant
    Filed: March 2, 2001
    Date of Patent: August 5, 2003
    Assignees: Hitachi, Ltd., Hitachi Device Engineering
    Inventors: Yoshihisa Ooishi, Hiroyuki Nitta, Akihiro Watanabe, Hirobumi Koshi, Satoru Tsunekawa
  • Patent number: 6392619
    Abstract: In a data transfer circuit, a hold signal generating circuit generates and outputs a hold signal Hold when transmission data is equal to transmission data one cycle before, and sets a 3-state output buffer for transmission data to high-impedance state, while, in a data reception circuit, when the hold signal Hold is valid, a data reception circuit outputs the reception data held, thereby power consumption in a data bus which is terminated with a terminal resistor is reduced.
    Type: Grant
    Filed: May 18, 1999
    Date of Patent: May 21, 2002
    Assignees: Hitachi, Ltd., Hitachi Video and Information System, Inc., Hitachi Device Engineering Co., Ltd.
    Inventors: Hiroyuki Nitta, Atsuhiro Higa, Masashi Nakamura, Satoru Tsunekawa, Hirobumi Koshi
  • Publication number: 20020011979
    Abstract: A liquid crystal driving device for controling a liquid crystal panel and a liquid crystal display apparatus. Reference voltages are generated in a data driver from input reference voltages, and reference voltages are selected in accordance with the settings of gray scale control registers thereby to control the gray scale voltages.
    Type: Application
    Filed: July 25, 2001
    Publication date: January 31, 2002
    Inventors: Hiroyuki Nitta, Tsutomu Furuhashi, Makoto Kimura, Hirobumi Koshi, Takeshi Maeda
  • Publication number: 20020003533
    Abstract: A liquid crystal display device includes a liquid crystal panel; a plurality of data drivers for applying, to the pixel elements, graduation voltages corresponding to the display data; a gate driver for selecting a pixel element to which a graduation voltage is to be applied; and a liquid crystal control circuit for controlling the data drivers on the basis of a transfer clock. Each data driver includes a reproducing circuit for reproducing the transfer clock input to the data driver such that the deviations between the duties of the display data and the transfer clock input to the data driver and the duties of the display data and the transfer clock output from the data driver become small, and for generating a latch clock, and a latch circuit for latching the display data input to the data driver.
    Type: Application
    Filed: March 2, 2001
    Publication date: January 10, 2002
    Inventors: Yoshihisa Ooishi, Hiroyuki Nitta, Akihiro Watanabe, Hirobumi Koshi, Satoru Tsunekawa
  • Patent number: 6166725
    Abstract: A liquid crystal display device includes a video signal line drive circuit which includes (1) a first drive voltage circuit including at least one first output circuit which outputs an LC driving voltage of positive polarity corresponding to display data, and at least one second output circuit which outputs an LC driving voltage of negative polarity corresponding to display data, the at least one first output circuit and the at least one second output circuit being arranged alternately in a first polarity order, (2) a second drive voltage circuit including at least one third output circuit which outputs an LC driving voltage of positive polarity corresponding to display data, and at least one fourth output circuit which outputs an LC driving voltage of negative polarity corresponding to the display data, the at least one third output circuit and the at least one fourth output circuit being arranged alternately in a second polarity order opposite to the first polarity order, (3) a first switching circuit which
    Type: Grant
    Filed: November 30, 1999
    Date of Patent: December 26, 2000
    Assignees: Hitachi, Ltd., Hitachi Device Engineering Co., Ltd.
    Inventors: Hironobu Isami, Hirobumi Koshi, Mitsuru Goto, Yukihide Ode, Hiroshi Watanabe
  • Patent number: 5995073
    Abstract: A method of driving the liquid crystal display device includes the steps of preparing a first drive voltage circuit formed by plural first output circuits having a latch circuit for latching display data and being connected to the latch circuit and outputting LC driving voltages of positive polarity and second output circuits having a latch circuit for latching display data and being connected to the latch circuit and outputting LC driving voltages of negative polarity arranged alternately, and a second drive voltage circuit formed by plural first output circuits having a latch circuit for latching display data and being connected to the latch circuit and outputting LC driving voltages of positive polarity and second output circuits having a latch circuit for latching display data and being connected to the latch circuit and outputting LC driving voltages of negative polarity arranged alternately in opposite polarity.
    Type: Grant
    Filed: April 9, 1997
    Date of Patent: November 30, 1999
    Assignees: Hitachi, Ltd., Hitachi Device Engineering Co., Ltd.
    Inventors: Hironobu Isami, Hirobumi Koshi, Mitsuru Goto, Yukihide Ode, Hiroshi Watanabe