Patents by Inventor Yoshiro Uchikawa

Yoshiro Uchikawa 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).

  • Liquid crystal video display device having pulse-width modulated "ON" signal for gradation display
    Patent number: 4743096
    Abstract: The present invention provides, in an active matrix liquid crystal display device of the type including non-linear elements, for the application of an ON pulse-width modulation signal by the data line driving circuit at the rearward end of each selected period, during which the voltage corresponding to the duty-cycle of the selected signal is applied to the liquid crystal layer. The result is accurate reproduction of gray-scale images in the display under conditions of high duty-cycle driving. Further, cross-talk between columns caused by the data signal is controlled by supplying a signal voltage which eliminates the residual charges in the liquid crystal layer at the end of each selected period.
    Type: Grant
    Filed: January 30, 1987
    Date of Patent: May 10, 1988
    Assignee: Seiko Epson Kabushiki Kaisha
    Inventors: Yoichi Wakai, Satoru Yazawa, Hiroaki Ikejiri, Yoshiro Uchikawa, Masahide Isuda
  • System for driving a liquid crystal matrix display so as to avoid crosstalk
    Patent number: 4640582
    Abstract: The invention relates to a system for driving a liquid crystal matrix display for use in a television wherein the signal applied to each pixel is inverted at a rate not greater than that necessary to scan a single pixel but greater than the rate necessary to cause crosstalk and in any event greater than the rate necessary to scan a line of pixels without inverting.
    Type: Grant
    Filed: May 7, 1984
    Date of Patent: February 3, 1987
    Assignee: Kabushiki Kaisha Seiko Epson
    Inventors: Kikuo Oguchi, Yoshiro Uchikawa