Patents by Inventor Ashfaqul I. Chowdhury

Ashfaqul I. Chowdhury 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: 20110242817
    Abstract: A heat sink includes a thermally conductive layer comprising at least one of fullerenes and nanotubes disposed in a polymeric host. The thermally conductive layer may be disposed on a heat sink body, which may be thermally insulating and/or plastic, and may include surface area enhancing heat radiating structures, such as fins, with the thermally conductive layer being disposed over at least the surface area enhancing heat radiating structures. A light emitting diode (LED)-based lamp embodiment includes the heat sink and an LED module including one or more LED devices secured with and in thermal communication with the heat sink. A method embodiment includes forming the heat sink body and disposing the thermally conductive layer on the heat sink body. The disposing may comprise spray coating. An external energy field may be applied during spray coating to impart a non-random orientation to nanotubes in the polymeric host.
    Type: Application
    Filed: December 28, 2010
    Publication date: October 6, 2011
    Inventors: Ashfaqul I. Chowdhury, Gray R. Allen, Joshua I. Rintamaki
  • Publication number: 20110242816
    Abstract: A heat sink comprises a heat sink body, which in some embodiments is a plastic heat sink body, and a thermally conductive layer disposed over the heat sink body. In some embodiments the thermally conductive layer comprises a copper layer. A light emitting diode (LED)-based lamp comprises the aforementioned heat sink and an LED module including one or more LED devices in which the LED module is secured with and in thermal communication with the heat sink. Some such LED-based lamps may have an A-line bulb configuration or an MR or PAR configuration. Disclosed method embodiments comprise forming a heat sink body and disposing a thermally conductive layer on the heat sink body. The forming may comprise molding the heat sink body, which may be plastic. In some method embodiments the heat sink body includes fins and the disposing includes disposing the thermally conductive layer over the fins.
    Type: Application
    Filed: December 28, 2010
    Publication date: October 6, 2011
    Inventors: Ashfaqul I. Chowdhury, Gary R. Allen, Thomas A. Knapp
  • Patent number: 7352118
    Abstract: A metal halide lamp (10) includes a light-transmissive envelope (12) which encloses a metal halide pool (30) for generating a discharge when spaced apart electrodes (20, 22) within the envelope are supplied with an electric current. A multi-layer coating (40) is deposited on a surface (42) of the envelope. The coating includes several layers of at least two materials of different refractive index, which, in combination, reflect radiation in the UV region of the electromagnetic spectrum. Rather than optimizing the coating for a normal (i.e., 0°) angle of incidence on the coating, the multi-layer coating is optimized at an angle which is selected to be within 10° of the mean angle (?) of incidence of the UV radiation on the arctube surface, thereby increasing the amount of UV radiation which is returned to the metal halide pool.
    Type: Grant
    Filed: December 10, 2003
    Date of Patent: April 1, 2008
    Assignee: General Electric Company
    Inventors: Ashfaqul I. Chowdhury, Rajasingh Israel, Gary R. Allen
  • Publication number: 20080036384
    Abstract: An electric lamp (12) includes a generally cylindrical lamp vessel (16) which encloses an interior space (18). A source of illumination (20) is disposed within the interior space. A reflective layer (28) is disposed on a light transmissive first end (22) of the lamp vessel. The reflective layer reflects light emitted by the source of illumination into the interior space. The lamp is suited to use in a vehicle headlamp. The reflective layer enables the lamp to have a higher efficiency than a conventional lamp with a black end coat.
    Type: Application
    Filed: August 9, 2006
    Publication date: February 14, 2008
    Inventors: Ashfaqul I. Chowdhury, Rajasingh S. Israel, Peter Brown, Tianji Zhao, Bart P. Terburg
  • Patent number: 6967443
    Abstract: A halogen infrared lamp (100) having an infrared reflective coating (118) along with a totally reflecting coating (120) on ends of an ellipsoidal portion of the envelope. The totally reflecting coating reflects the infrared radiation escaping at acute angles and directs the infrared radiation towards the filament to increase the temperature of the filament and thus increase the efficacy of the lamp. The totally reflecting coating may also extend to portions of tubular members extending from the ellipsoidal portion of the envelope.
    Type: Grant
    Filed: November 14, 2003
    Date of Patent: November 22, 2005
    Assignee: General Electric Company
    Inventors: Laurence Bigio, Rajasingh Israel, Ashfaqul I. Chowdhury, Laszlo Lieszkovszky
  • Publication number: 20040104678
    Abstract: A halogen infrared lamp (100) having an infrared reflective coating (118) along with a totally reflecting coating (120) on ends of an ellipsoidal portion of the envelope. The totally reflecting coating reflects the infrared radiation escaping at acute angles and directs the infrared radiation towards the filament to increase the temperature of the filament and thus increase the efficacy of the lamp. The totally reflecting coating may also extend to portions of tubular members extending from the ellipsoidal portion of the envelope.
    Type: Application
    Filed: November 14, 2003
    Publication date: June 3, 2004
    Applicant: General Electric Company
    Inventors: Laurence Bigio, Rajasingh Israel, Ashfaqul I. Chowdhury, Laszlo Lieszkovszky