Patents by Inventor Katuyuki Hunahata

Katuyuki Hunahata 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 display device using nematic liquid crystal having twisted helical structure and a phase correction plate
    Patent number: 4906073
    Abstract: In a liquid crystal display device, light transmitting through a liquid crystal layer is colored depending on the structural conditions of the liquid crystal display device. The phase of the transmission light is corrected by means of a phase correction plate to make the transmission light approximate achromatic color, thereby permitting monochromatic display or color display.
    Type: Grant
    Filed: July 27, 1988
    Date of Patent: March 6, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Katuyuki Hunahata, Yuji Mori, Jun-ichi Hirakata, Yoshiharu Nagae, Hideaki Kawakami, Kiyoshige Kinugawa, Yasuhiko Kando
  • Projector using guest-host liquid crystal cells for improved color purity
    Patent number: 4838655
    Abstract: The disclosure relates to a projector having an arrangement of polarizers and liquid crystal cells aligned on the axis of light in the order a first color polarizer colored in red, a first twisted nematic liquid crystal cell, a second twisted nematic liquid crystal cell, a second color polarizer colored in a green, a third twisted nematic liquid, a neutral polarizer and Guest-Host type colored in blue. Since, according to this, a polarizer having inferior color characteristics can be replaced by a Guest-Host type liquid crystal cell, the excitation purity and the scope of color reproduction are improved. Further, since the mixture of color is additive, the brightness of the reproduced color is also much improved.
    Type: Grant
    Filed: January 6, 1988
    Date of Patent: June 13, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Katuyuki Hunahata, Yoshiharu Nagae, Masahiro Takasaka, Yuji Mori, Minoru Hoshino, Yasuyuki Kozima, Youhei Saito, Kyohei Fukuda, Hayao Kozai, Tadahiko Hasimoto, Yoshiaki Tsuchihashi