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).
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Publication number: 20050036077Abstract: 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: ApplicationFiled: September 22, 2003Publication date: February 17, 2005Inventors: Asad Khan, Xiao-Yang Huang, Haiji Yuan, Minhua Lu
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Patent number: 6830789Abstract: 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: GrantFiled: September 24, 2001Date of Patent: December 14, 2004Assignees: Kent Displays, Inc., Kent State UniversityInventors: Joseph W. Doane, Asad A. Khan, Alexander J. Seed
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Patent number: 6654080Abstract: 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: GrantFiled: June 10, 1999Date of Patent: November 25, 2003Assignee: Kent Displays, Inc.Inventors: Asad A. Khan, Xiao-Yang Huang, Haiji Yuan, Minhua Lu
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Molybdenum and vanadium based catalysts for the oxidation of alkanes to carboxylic acids and olefins
Patent number: 6638891Abstract: 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: GrantFiled: January 7, 2003Date of Patent: October 28, 2003Assignee: Saudi Basic Industries CorporationInventors: Khalid Karim, Mohammad H. Al-Hazmi, Asad Khan, Syed Irshad Zaheer -
Patent number: 6532052Abstract: 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: GrantFiled: August 23, 1999Date of Patent: March 11, 2003Assignee: Kent Displays, Inc.Inventors: Asad A. Khan, Xiao-Yang Huang, J. William Doane, Gene A. Miceli, Donald J. Davis
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Publication number: 20020187281Abstract: 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: ApplicationFiled: September 24, 2001Publication date: December 12, 2002Inventors: Joseph W. Doane, Asad A. Khan, Alexander J. Seed
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Patent number: 6483563Abstract: 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: GrantFiled: October 9, 2001Date of Patent: November 19, 2002Assignee: Kent Displays, Inc.Inventors: Asad A. Khan, Xiao-Yang Huang, J. William Doane, Gene A. Miceli, Donald J. Davis
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Publication number: 20020101554Abstract: 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: ApplicationFiled: October 9, 2001Publication date: August 1, 2002Applicant: Kent Displays IncorporatedInventors: Asad A. Khan, Xiao-Yang Huang, J. William Doane, Gene A. Miceli, Donald J. Davis
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Patent number: 6377321Abstract: 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: GrantFiled: June 10, 1999Date of Patent: April 23, 2002Assignee: Kent Displays, Inc.Inventors: Asad A. Khan, Xiao-Yang Huang, Haiji Yuan, Minhua Lu, Ellison C. Urban
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Publication number: 20020030776Abstract: 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: ApplicationFiled: September 24, 2001Publication date: March 14, 2002Applicant: Kent Displays IncorporatedInventors: Asad A. Khan, Michael E. Stefanov, Clive Catchpole
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Patent number: 6258992Abstract: 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: GrantFiled: September 17, 1999Date of Patent: July 10, 2001Assignee: Saudi Basic Industries CorporationInventors: Khalid Karim, Asad Khan
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Patent number: 6156928Abstract: 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: GrantFiled: February 8, 2000Date of Patent: December 5, 2000Assignee: Saudi Basic Industries CorporationInventors: Khalid Karim, M. H. Al-Hazmi, Asad Khan
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Patent number: 6130356Abstract: 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: GrantFiled: February 14, 2000Date of Patent: October 10, 2000Assignee: Saudi Basic Industries CorporationInventors: Khalid Karim, Mohammad Al-Hazmi, Asad Khan
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Patent number: 6087297Abstract: 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: GrantFiled: June 29, 1998Date of Patent: July 11, 2000Assignee: Saudi Basic Industries CorporationInventors: Khalid Karim, Mohammad H. Al-Hazmi, Asad Khan
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Patent number: 6034752Abstract: 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: GrantFiled: March 22, 1997Date of Patent: March 7, 2000Assignee: Kent Displays IncorporatedInventors: Asad A. Khan, Ellison C. Urban, II, Donald J. Davis, Xiao-Yang Huang, Kellie D. Hoke
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Patent number: 5077929Abstract: 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: GrantFiled: July 22, 1991Date of Patent: January 7, 1992Inventor: Asad A. Khan