Patents by Inventor Yumi Baba

Yumi Baba 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 with compensators
    Patent number: 5493431
    Abstract: A liquid crystal display device of stable color tone uses phase difference plates made of a uniaxially stretched polymer film and comprises a polarizer plate, a first phase difference plate, a second phase difference plate, a supertwisted nematic type liquid crystal display panel, and a polarizer plate which are stacked on each other in this order. The rate of retardation change with the change in viewing angle of the uniaxially stretched polymer film is denoted coefficient K defined by three-dimensional refractive indexes, coefficient K1 of one of the phase difference plates is set in a range of -1.ltoreq.K1.ltoreq.0.17 and coefficient K2 of the other phase difference plate is set in a range of 0.ltoreq.K2.ltoreq.1.
    Type: Grant
    Filed: January 28, 1993
    Date of Patent: February 20, 1996
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yumi Baba, Hiroshi Ohnishi, Toshiyuki Yoshimizu, Keiko Kishimoto