Patents by Inventor Calvin Ma

Calvin Ma 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: 6344887
    Abstract: This invention is related to a full spectrum reflective or tranmissive black-and-white cholesteric liquid crystal display. The white state is realized by a full gamut of light reflection or transmission in the display's planar texture, and the black state is created by cholesterics' scattering type depolarization effect and polarizer's filtration effect in the display's focal conic texture. It has been discovered that the scattering depolarization effect and multi-filtration process can generate a black dark state, the optical “off” state in focal conic texture of cholesteric liquid crystals. In the dark-and-white cholesterics display can be easily upgraded to a full color display by means of micro-color filter structure in both front and back illuminating systems.
    Type: Grant
    Filed: September 10, 1999
    Date of Patent: February 5, 2002
    Inventors: Yao-Dong Ma, Calvin Ma