Patents by Inventor Asad A. Khan

Asad A. Khan 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).

  • Publication number: 20050036077
    Abstract: A liquid crystal display device includes cell wall structure and a chiral nematic liquid crystal material. The cell wall structure and the liquid crystal cooperate to form focal conic and twisted planar textures that are stable in the absence of a field. A device applies an electric field to the liquid crystal for transforming at least a portion of the material to at least one of the focal conic and twisted planar textures. The liquid crystal material has a pitch length effective to reflect radiation having a wavelength in both the visible and the infrared ranges of the electromagnetic spectrum at intensity that is sufficient for viewing by an observer. One liquid crystal material may be disposed in a single region or two or more liquid crystal materials may be used, each in separate regions even without the infrared reflecting layer. One aspect of the invention is directed to a photolithography method for patterning a substrate of the display.
    Type: Application
    Filed: September 22, 2003
    Publication date: February 17, 2005
    Inventors: Asad Khan, Xiao-Yang Huang, Haiji Yuan, Minhua Lu
  • Patent number: 6830789
    Abstract: A unique class of chiral additive materials is disclosed for use in cholesteric displays that possess a helical twist power substantially independent of temperature. The additives have a solubility and a helical twist power large enough to be used as a single chiral component with little dilution of the physical properties of the nematic liquid crystal host mixture. The chiral additives may be used in combination with non-chiral additives to provide a helical twisting power substantially independent of temperature suitable for cholesteric displays.
    Type: Grant
    Filed: September 24, 2001
    Date of Patent: December 14, 2004
    Assignees: Kent Displays, Inc., Kent State University
    Inventors: Joseph W. Doane, Asad A. Khan, Alexander J. Seed
  • Patent number: 6654080
    Abstract: A liquid crystal display device includes cell wall structure and a chiral nematic liquid crystal material. The cell wall structure and the liquid crystal cooperate to form focal conic and twisted planar textures that are stable in the absence of a field. A device applies an electric field to the liquid crystal for transforming at least a portion of the material to at least one of the focal conic and twisted planar textures. The liquid crystal material has a pitch length effective to reflect radiation having a wavelength in both the visible and the infrared ranges of the electromagnetic spectrum at intensity that is sufficient for viewing by an observer. One liquid crystal material may be disposed in a single region or two or more liquid crystal materials may be used, each in separate regions even without the infrared reflecting layer. One aspect of the invention is directed to a photolithography method for patterning a substrate of the display.
    Type: Grant
    Filed: June 10, 1999
    Date of Patent: November 25, 2003
    Assignee: Kent Displays, Inc.
    Inventors: Asad A. Khan, Xiao-Yang Huang, Haiji Yuan, Minhua Lu
  • Patent number: 6638891
    Abstract: A mixed metal oxide catalytic system for producing olefins and carboxylic acids from lower alkanes comprising a catalyst composition having the formula MoaVbAlcXdYeOz wherein: X is at least one element selected from the group consisting of W and Mn; Y is at least one element selected from the group consisting of Pd, Sb, Ca, P, Ga, Ge, Si, Mg, Nb, and K; a is 1; b is 0.01 to 0.9; c is >0 to 0.2; d is >0 to 0.5; e is >0 to 0.5; and z is an integer representing the number of oxygen atoms required to satisfy the valency of Mo, V, Al, X, and Y.
    Type: Grant
    Filed: January 7, 2003
    Date of Patent: October 28, 2003
    Assignee: Saudi Basic Industries Corporation
    Inventors: Khalid Karim, Mohammad H. Al-Hazmi, Asad Khan, Syed Irshad Zaheer
  • Patent number: 6532052
    Abstract: The present invention is directed to a cholesteric liquid crystal display that includes a homogeneous alignment surface effective to provide increased brightness, low focal conic reflectance and/or reflected light treat is to a significant degree circularly polarized. The homogeneous alignment surface substantially homogeneously aligns the liquid crystal director adjacent thereto. The homogeneous alignment surface may be disposed on one or both sides of a cell of the display. In the case of a cell in which the homogeneous alignment surface is disposed on only one side, the substrate with the inhomogeneous alignment surface may be upstream or downstream of the substrate with the homogeneous alignment surface relative to a direction of incident light. Also included especially in the case of a cell that has the homogeneous alignment surface on both sides is the use of a polarizer to provide very good brightness and low focal conic reflectance.
    Type: Grant
    Filed: August 23, 1999
    Date of Patent: March 11, 2003
    Assignee: Kent Displays, Inc.
    Inventors: Asad A. Khan, Xiao-Yang Huang, J. William Doane, Gene A. Miceli, Donald J. Davis
  • Publication number: 20020187281
    Abstract: A unique class of chiral additive materials is disclosed for use in cholesteric displays that possess a helical twist power substantially independent of temperature. The additives have a solubility and a helical twist power large enough to be used as a single chiral component with little dilution of the physical properties of the nematic liquid crystal host mixture. The chiral additives may be used in combination with non-chiral additives to provide a helical twisting power substantially independent of temperature suitable for cholesteric displays.
    Type: Application
    Filed: September 24, 2001
    Publication date: December 12, 2002
    Inventors: Joseph W. Doane, Asad A. Khan, Alexander J. Seed
  • Patent number: 6483563
    Abstract: The present invention is directed to a cholesteric liquid crystal display that includes a homogeneous alignment surface effective to provide increased brightness, low focal conic reflectance and/or reflected light that is to a significant degree circularly polarized. The homogeneous alignment surface substantially homogeneously aligns the liquid crystal director adjacent thereto. The homogeneous alignment surface may be disposed on one or both sides of a cell of the display. In the case of a cell in which the homogeneous alignment surface is disposed on only one side, the substrate with the inhomogeneous alignment surface may be upstream or downstream of the substrate with the homogeneous alignment surface relative to a direction of incident light. Also included especially in the case of a cell that has the homogeneous alignment surface on both sides is the use of a polarizer to provide very good brightness and low focal conic reflectance.
    Type: Grant
    Filed: October 9, 2001
    Date of Patent: November 19, 2002
    Assignee: Kent Displays, Inc.
    Inventors: Asad A. Khan, Xiao-Yang Huang, J. William Doane, Gene A. Miceli, Donald J. Davis
  • Publication number: 20020101554
    Abstract: The present invention is directed to a cholesteric liquid crystal display that includes a homogeneous alignment surface effective to provide increased brightness, low focal conic reflectance and/or reflected light that is to a significant degree circularly polarized. The homogeneous alignment surface substantially homogeneously aligns the liquid crystal director adjacent thereto. The homogeneous alignment surface may be disposed on one or both sides of a cell of the display. In the case of a cell in which the homogeneous alignment surface is disposed on only one side, the substrate with the inhomogeneous alignment surface may be upstream or downstream of the substrate with the homogeneous alignment surface relative to a direction of incident light. Also included especially in the case of a cell that has the homogeneous alignment surface on both sides is the use of a polarizer to provide very good brightness and low focal conic reflectance.
    Type: Application
    Filed: October 9, 2001
    Publication date: August 1, 2002
    Applicant: Kent Displays Incorporated
    Inventors: Asad A. Khan, Xiao-Yang Huang, J. William Doane, Gene A. Miceli, Donald J. Davis
  • Patent number: 6377321
    Abstract: A liquid crystal display device includes cell wall structure and a chiral nematic liquid crystal material. The cell wall structure and the liquid crystal cooperate to form focal conic and twisted planar textures that are stable in the absence of a field. A device applies an electric field to the liquid crystal for transforming at least a portion of the material to at least one of the focal conic and twisted planar textures. The liquid crystal material has a pitch length effective to reflect radiation having a wavelength in both the visible and the infrared ranges of the electromagnetic spectrum at intensity that is sufficient for viewing by an observer. One liquid crystal material may be disposed in a single region or two or more liquid crystal materials may be used, each in separate regions even without the infrared reflecting layer. One aspect of the invention is directed to a photolithography method for patterning a substrate of the display.
    Type: Grant
    Filed: June 10, 1999
    Date of Patent: April 23, 2002
    Assignee: Kent Displays, Inc.
    Inventors: Asad A. Khan, Xiao-Yang Huang, Haiji Yuan, Minhua Lu, Ellison C. Urban
  • Publication number: 20020030776
    Abstract: A reflective cholesteric display that may be viewed under a wide range of ambient lighting conditions, ranging from complete darkness to bright sunlight. The display includes a chiral nematic liquid crystal material located between first and second substrates, an ambidextrous or bi-directional circular polarizer, a partial mirror, also referred to as a transflector, and a light source. The liquid crystal material includes focal conic and planar textures that are stable in the absence of an electric field. The ambidextrous circular polarizer is located adjacent to one of the substrates that constrain the liquid crystal material. The chiral nematic liquid crystal display may be operated in both a transmissive mode and a reflective mode.
    Type: Application
    Filed: September 24, 2001
    Publication date: March 14, 2002
    Applicant: Kent Displays Incorporated
    Inventors: Asad A. Khan, Michael E. Stefanov, Clive Catchpole
  • Patent number: 6258992
    Abstract: Lower hydrocarbons are converted to carboxylic acids and/or dehydrogenated hydrocarbon product by contacting a feed mixture containing lower hydrocarbons, oxygen source, diluent, and sulfur-containing compound, with a multifunctional, mixed metal catalyst at a temperature from about 150° C. up to about 400° C. The lower hydrocarbons include C2-C4, and the presence of sulfur compound in the feed mixture results in increased yield of carboxylic acid and/or dehydrogenated hydrocarbon product.
    Type: Grant
    Filed: September 17, 1999
    Date of Patent: July 10, 2001
    Assignee: Saudi Basic Industries Corporation
    Inventors: Khalid Karim, Asad Khan
  • Patent number: 6156928
    Abstract: A mixed metal oxide catalytic system consisting of molybdenum, vanadium, lanthanum and palladium providing higher yields of acetic acid in low temperature single stage oxidation of ethane with molecular oxygen-containing gas without or with reduced production of by-products such as ethylene and CO.
    Type: Grant
    Filed: February 8, 2000
    Date of Patent: December 5, 2000
    Assignee: Saudi Basic Industries Corporation
    Inventors: Khalid Karim, M. H. Al-Hazmi, Asad Khan
  • Patent number: 6130356
    Abstract: A mixed metal oxide MoVLaPdNbXO catalytic system (wherein X=Al, Ga, Ge and/or Si) providing higher selectivity and space time yield of acetic acid at low pressure and low temperature in a single stage oxidation of ethane with a molecular oxygen-containing gas and steam.
    Type: Grant
    Filed: February 14, 2000
    Date of Patent: October 10, 2000
    Assignee: Saudi Basic Industries Corporation
    Inventors: Khalid Karim, Mohammad Al-Hazmi, Asad Khan
  • Patent number: 6087297
    Abstract: A mixed metal oxide catalytic system consisting of molybdenum, vanadium, lanthanum and palladium providing higher yields of acetic acid in low temperature single stage oxidation of ethane with molecular oxygen-containing gas without or with reduced production of by-products such as ethylene and CO.
    Type: Grant
    Filed: June 29, 1998
    Date of Patent: July 11, 2000
    Assignee: Saudi Basic Industries Corporation
    Inventors: Khalid Karim, Mohammad H. Al-Hazmi, Asad Khan
  • Patent number: 6034752
    Abstract: A liquid crystal display device includes cell wall structure and a chiral nematic liquid crystal material. The cell wall structure and the liquid crystal cooperate to form focal conic and twisted planar textures that are stable in the absence of a field. A device applies an electric field to the liquid crystal for transforming at least a portion of the material to at least one of the focal conic and twisted planar textures. The liquid crystal material has a pitch length effective to reflect radiation having a wavelength in both the visible and the infrared ranges of the electromagnetic spectrum at intensity that is sufficient for viewing by an observer. One liquid crystal material may be disposed in a single region or two liquid crystal materials may be used, each in separate regions. One aspect of the invention is directed to a photolithography method for patterning a substrate of the display. The display may also have multicolor capabilities by including at least two materials that reflect visible light.
    Type: Grant
    Filed: March 22, 1997
    Date of Patent: March 7, 2000
    Assignee: Kent Displays Incorporated
    Inventors: Asad A. Khan, Ellison C. Urban, II, Donald J. Davis, Xiao-Yang Huang, Kellie D. Hoke
  • Patent number: 5077929
    Abstract: A self-propelled fishing device is described which can be used to tow a fishing line away from shore or from a stationary fishing boat. The device may be used to carry lures or baited hooks. It can be made to turn, submerge or move to a desired position and stop by a series of tugs on the fishing line. It can be reeled in or guided along a return path.
    Type: Grant
    Filed: July 22, 1991
    Date of Patent: January 7, 1992
    Inventor: Asad A. Khan