Patents by Inventor Karl A. Crandall

Karl A. Crandall 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).

  • Cholesteric liquid crystal devices
    Patent number: 5602662
    Abstract: A liquid crystal cell including chiral nematic liquid material with negative dielectric anisotropy. The cell is placed between two orthogonal polarizers. In the absence of an applied field, the liquid crystal molecules assume a homeotropic alignment. The liquid crystal molecules assume a twisted pattern in the field-on state.
    Type: Grant
    Filed: February 16, 1995
    Date of Patent: February 11, 1997
    Assignee: Case Western Reserve University
    Inventors: Charles Rosenblatt, Michael R. Fisch, Karl A. Crandall, Rolfe Petschek
  • Chiral nematic liquid crystal display with homeotropic alignment and negative dielectric anisotropy
    Patent number: 5477358
    Abstract: A liquid crystal cell including chiral nematic liquid material with negative dielectric anisotropy. The cell is placed between two orthogonal polarizers. In the absence of an applied field, the liquid crystal molecules assume a homeotropic alignment. The liquid crystal molecules assume a twisted pattern in the field-on state.
    Type: Grant
    Filed: June 21, 1993
    Date of Patent: December 19, 1995
    Assignee: Case Western Reserve University
    Inventors: Charles Rosenblatt, Michael R. Fisch, Karl A. Crandall, Rolfe Petschek