Patents by Inventor Koichiro Shirota

Koichiro Shirota 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: 5307187
    Abstract: A liquid crystal display element comprises a liquid crystal material having a resistivity .rho..sub.LC (.OMEGA..multidot.cm) and a polymer matrix material having a resistivity .rho..sub.p (.OMEGA..multidot.cm). The ratio .rho..sub.LC /.rho..sub.p is defined to fall within a range of between 1 and 10.sup.5 (1.ltoreq..rho..sub.LC /.rho..sub.p .ltoreq.10.sup.5). Also, the particles diameters of the polymer matrix material or the liquid crystal material are distributed such that at least two peaks each having a half value width of at least 0.5 .mu.m are present within a range of between 0.5 .mu.m and 2.5 .mu.m. Further, a protective layer is formed to cover the outer surface of the liquid crystal material. The particular construction permits manufacturing a polymer dispersion type liquid crystal display element, which exhibits a high response speed, which can be operated with a low driving voltage, and which permits a high contrast.
    Type: Grant
    Filed: June 26, 1992
    Date of Patent: April 26, 1994
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kazuyuki Sunohara, Koichiro Shirota, Kenji Sano
  • Patent number: 5303073
    Abstract: A liquid crystal display element having a pair of substrates at least one of which is transparent, and a light control layer consisting of a dispersion type liquid crystal material held between the substrates. The dispersion type liquid crystal material consists of a supporting medium, liquid crystal molecules and a dichromatic dye which is oriented within the supporting medium. It is desirable to arrange a polarized light selecting element to cover the outer surface of one of the substrates.
    Type: Grant
    Filed: June 24, 1992
    Date of Patent: April 12, 1994
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koichiro Shirota, Kazuyuki Sunohara