Patents by Inventor Rudolf Dennstedt

Rudolf Dennstedt 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: 8815120
    Abstract: The present invention relates to alkaline earth metal silicate luminophores having improved long-term stability and to a corresponding method for improving the long-term stability of alkaline earth metal silicate luminophores. The luminophore according to the invention is a luminophore comprising a base lattice according to the general chemical formula EAxSiyOz, where x, y, z>0. The component EA is formed by one or more alkaline earth metals. An activator, for example Eu2+ or Mn2+, is doped into the base lattice. The luminophore has the fundamental property to absorb radiation in a first wavelength range and emit radiation in a second wavelength range that is different from the first wavelength range. The luminophore is designed in the form of crystals. According to the invention, the surfaces of the crystals of the luminophore are chemically modified such that at least portions of the surfaces thereof are formed by a chemical compound of the general formula EauZ2.
    Type: Grant
    Filed: October 14, 2010
    Date of Patent: August 26, 2014
    Assignee: Leuchtstoffwerk Breitungen GmbH
    Inventors: Wolfgang Kempfert, Sylke Rosler, Sven Rosler, Cheng-Jun Duan, Rudolf Dennstedt
  • Publication number: 20120193579
    Abstract: The present invention relates to alkaline earth metal silicate luminophores having improved long-term stability and to a corresponding method for improving the long-term stability of alkaline earth metal silicate luminophores. The luminophore according to the invention is a luminophore comprising a base lattice according to the general chemical formula EAxSiyOz, where x, y, z>0. The component EA is formed by one or more alkaline earth metals. An activator, for example Eu2? or Mn2?, is doped into the base lattice. The luminophore has the fundamental property to absorb radiation in a first wavelength range and emit radiation in a second wavelength range that is different from the first wavelength range. The luminophore is designed in the form of crystals. According to the invention, the surfaces of the crystals of the luminophore are chemically modified such that at least portions of the surfaces thereof are formed by a chemical compound of the general formula EauZ2.
    Type: Application
    Filed: October 10, 2010
    Publication date: August 2, 2012
    Applicant: LEUCHTSTOFFWERK BREITUNGEN GMBH
    Inventors: Wolfgang Kempfert, Sylke Rosler, Sven Rosler, Cheng-Jun Duan, Rudolf Dennstedt