Patents by Inventor Hristina Galabova

Hristina Galabova 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: 6831720
    Abstract: A color liquid crystal display using reflective color filters using layers of cholesteric liquid crystals is disclosed. The reflective color filters have two different center wavelengths and bandwidths per layer and are stacked in two layers to provide colored light for displays. With various numbers of layers in the stack, different polarization levels are provided. The pixels in the display of the invention are arranged such that multiple adjacent sub-pixels in a layer with the same color makes the color filters easier to manufacture.
    Type: Grant
    Filed: May 30, 2003
    Date of Patent: December 14, 2004
    Assignee: Reveo, Inc.
    Inventors: Yingqiu Jiang, Le Li, Aharon Hochbaum, Sameer Vartak, Hristina Galabova, Richard Wiley, Sadeg M. Faris
  • Publication number: 20040095531
    Abstract: A color liquid crystal display using reflective color filters using layers of cholesteric liquid crystals is disclosed. The reflective color filters have two different center wavelengths and bandwidths per layer and are stacked in two layers to provide colored light for displays. With various numbers of layers in the stack, different polarization levels are provided. The pixels in the display of the invention are arranged such that multiple adjacent sub-pixels in a layer with the same color makes the color filters easier to manufacture.
    Type: Application
    Filed: May 30, 2003
    Publication date: May 20, 2004
    Inventors: Yingqiu Jiang, Le Li, Aharon Hochbaum, Sameer Vartak, Hristina Galabova, Richard Wiley, Sadeg M. Faris
  • Patent number: 6630974
    Abstract: Cholesteric liquid crystal films using varying pitch helix structures aligned perpendicular to the surface of the film for broadband reflection and transmission of circularly polarized light distort the light at large viewing angles of incidence due to the elliptical cross section of the CLC helix with the light at large incident angles. By using compensating films of an infrared cholesteric liquid crystal to rotate the major axis of the elliptical light to ±45 degrees and a homeotropic film having elongated molecules with the long axis perpendicular to the surface of the film to convert the elliptically adjusted light from the IR CLC film to circularly polarized light, the distortions at large angles can be eliminated. The compensated light will be circularly polarized for large angles of incidence over a broad band.
    Type: Grant
    Filed: May 14, 1999
    Date of Patent: October 7, 2003
    Assignee: Reveo, Inc.
    Inventors: Hristina Galabova, Le Li
  • Patent number: 6573961
    Abstract: Reflective color filters using layers of cholesteric liquid crystals with two different center wavelengths and bandwidths per layer are stacked in two layers to provide colored light for displays. With a two layer stack circularly polarized light of one handedness can be provided. With a two layer stack circulary unpolarized colored light can be provided. With a broadband polarizing filter overlapping other filters in the stack a black matrix can be provided by reflecting all colors and transmitting no light in the overlapping areas. When broadband reflective cholesteric liquid crystals are used two primary colors can be reflected in the same pixel of a display making reflective layers with two reflective portions per layer possible. Color displays having three linear sub-pixels with three primary colors or with four sub-pixels of white, blue, green, and red in a pixel with two colors in a top row and two colors on a bottom row can are made with two colors per layer in two layer stacks.
    Type: Grant
    Filed: May 17, 1999
    Date of Patent: June 3, 2003
    Assignee: Reveo, Inc.
    Inventors: Yingqiu Jiang, Le Li, Aharon Hochbaum, Sameer Vartak, Hristina Galabova, Richard Wiley, Sadeg M. Faris
  • Publication number: 20020113921
    Abstract: Reflective color filters using layers of cholesteric liquid crystals with two different center wavelengths and bandwidths per layer are stacked in two layers to provide colored light for displays. With a two layer stack circularly polarized light of one handedness can be provided. With a four layer stack unpolarized colored light can be provided. With a broadband polarizing filter overlapping other filters in the stack a black matrix can be provided by reflecting all colors and transmitting no light in the overlapping areas. When broadband reflective cholesteric liquid crystals are used two primary colors can be reflected in the same pixel of a display making reflective layers with two reflective portions per layer possible. Color displays having three linear sub-pixels with three primary colors or with four sub-pixels of white, blue, green, and red in a pixel with two colors in a top row and two colors on a bottom row can are made with two colors per layer in two layer stacks.
    Type: Application
    Filed: May 17, 1999
    Publication date: August 22, 2002
    Inventors: YINGQIU JIANG, LE LI, AHARON HOCHBAUM, SAMEER VARTAK, HRISTINA GALABOVA, RICHARD WILEY, SADEG M. FARIS