Patents by Inventor Liang-Chy Chien

Liang-Chy Chien 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: 5695682
    Abstract: A new liquid crystalline light modulating cell and material are characterized by liquid crystalline light modulating material of liquid crystal and polymer, the liquid crystal being a chiral nematic liquid crystal having positive dielectric anisotropy and including chiral material in an amount effective to form focal conic and twisted planar textures, the polymer being distributed in phase separated domains in the liquid crystal cell in an amount that stabilizes the focal conic and twisted planar textures in the absence of a field and permits the liquid crystal to change textures upon the application of a field. In one embodiment, the material is light scattering in a field-OFF condition and optically clear in a field-ON condition, while in another embodiment, the material is optically clear in a field-OFF condition and light scattering in a field-ON condition.
    Type: Grant
    Filed: February 24, 1997
    Date of Patent: December 9, 1997
    Assignee: Kent State University
    Inventors: J. William Doane, Deng-ke Yang, Liang-Chy Chien
  • Patent number: 5691795
    Abstract: A new liquid crystalline light modulating cell and material are characterized by liquid crystalline light modulating material of liquid crystal and polymer, the liquid crystal being a chiral nematic liquid crystal having positive dielectric anisotropy and including chiral material in an amount effective to form focal conic and twisted planar textures, the polymer being distributed in phase separated domains in the liquid crystal cell in an amount that stabilizes the focal conic and twisted planar textures in the absence of a field and permits the liquid crystal to change textures upon the application of a field. In one embodiment, the material is light scattering in a field-OFF condition and optically clear in a field-ON condition, while in another embodiment, the material is optically clear in a field-OFF condition and light scattering in a field-ON condition.
    Type: Grant
    Filed: April 20, 1995
    Date of Patent: November 25, 1997
    Assignee: Kent State University
    Inventors: J. William Doane, Deng-Ke Yang, Liang-Chy Chien
  • Patent number: 5668614
    Abstract: An improvement in a light modulating chiral nematic liquid crystal adapted to form focal conic and twisted planar textures and a liquid crystal device employing such a material, the improvement wherein the liquid crystal material includes a plurality of essentially distinct regions within which the liquid crystal has different pitch lengths, whereby the liquid crystal can be made to reflect different wavelengths of light in different regions. The regions are created by including in the chiral nematic liquid crystal composition, a chiral material adapted to change its chirality upon photo-irradiation, in an amount effective to change the pitch length of the liquid crystal composition upon photo-irradiation. By exposing different regions of the material to increasing amounts of photo-irradiation, the pitch length of each region can be selectively tuned to reflect light of a different wavelength.
    Type: Grant
    Filed: May 1, 1995
    Date of Patent: September 16, 1997
    Assignee: Kent State University
    Inventors: Liang-Chy Chien, Joseph William Doane
  • Patent number: 5437811
    Abstract: A new liquid crystalline light modulating cell and material are characterized by liquid crystalline light modulating material of liquid crystal and polymer, the liquid crystal being a chiral nematic liquid crystal having positive dielectric anisotropy and including chiral material in an amount effective to form focal conic and twisted planar textures, the polymer being distributed in phase separated domains in the liquid crystal cell in an amount that stabilizes the focal conic and twisted planar textures in the absence of a field and permits the liquid crystal to change textures upon the application of a field. In one embodiment, the material is light scattering in a field-OFF condition and optically clear in a field-ON condition, while in another embodiment, the material is optically clear in a field-OFF condition and light scattering in a field-ON condition.
    Type: Grant
    Filed: October 30, 1992
    Date of Patent: August 1, 1995
    Assignee: Kent State University
    Inventors: J. William Doane, Deng-ke Yang, Liang-Chy Chien