Patents by Inventor Wolfgang Kempfert

Wolfgang Kempfert 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
  • Patent number: 7855393
    Abstract: The invention relates to a light emitting device having a radiation emitting element, for example a light emitting diode, and a luminescent material which is able to absorb a part of the radiation sent out by the radiation emitting element and to send out light with a wavelength which is different from the wavelength of the absorbed radiation. The device further has diffusing particles which are able to scatter a part of the radiation sent out by the radiation emitting element, and/or to scatter a part of the light sent out by the luminescent material. The diffusing particles are of non-activated luminescent material, through which production is simplified.
    Type: Grant
    Filed: January 8, 2007
    Date of Patent: December 21, 2010
    Assignee: Tridonic Optoelectronics GmbH
    Inventors: Sven Rösler, Sylke Rösler, Wolfgang Kempfert, Detlef Starick, Peter Pachler, Stefan Tasch, Paul Hartmann, Hans Hoschopf
  • Patent number: 7679101
    Abstract: The light emitting device has a light emitting diode which is made of a nitride semiconductor and a phosphor which absorbs a part of lights emitted from the light emitting diode and emits different lights with wavelengths other than those of the absorbed lights. The phosphor is made of alkaline earth metal silicate fluorescent material activated with europium.
    Type: Grant
    Filed: November 30, 2006
    Date of Patent: March 16, 2010
    Assignees: Toyoda Gosei Co., Ltd., Tridonic Optoelectronics GmbH, Litec GBR, Leuchstoffwerk Breitungen GmbH
    Inventors: Koichi Ota, Atsuo Hirano, Akihito Ota, Stefan Tasch, Peter Pachler, Gundula Roth, Walter Tews, Wolfgang Kempfert, Detlef Starick
  • Publication number: 20090294788
    Abstract: The invention relates to a light emitting device having a radiation emitting element, for example a light emitting diode, and a luminescent material which is able to absorb a part of the radiation sent out by the radiation emitting element and to send out light with a wavelength which is different from the wavelength of the absorbed radiation. The device further has diffusing particles which are able to scatter a part of the radiation sent out by the radiation emitting element, and/or to scatter a part of the light sent out by the luminescent material. The diffusing particles are of non-activated luminescent material, through which production is simplified.
    Type: Application
    Filed: January 8, 2007
    Publication date: December 3, 2009
    Applicant: TRIDONIC OPTOELECTRONICS GMBH
    Inventors: Sven Rosler, Sylke Rosler, Wolfgang Kempfert, Detlef Starick, Peter Pachler, Stefan Tasch, Paul Hartmann, Hans Hoschopf
  • Patent number: 7259396
    Abstract: The invention relates to a light source comprising a light-emitting element, which emits light in a first spectral region, and comprising a luminophore, which comes from the group of alkaline-earth orthosilicates and which absorbs a portion of the light emitted by the light source and emits light in another spectral region. According to the invention, the luminophore is an alkaline-earth orthosilicate, which is activated with bivalent europium and whose composition consists of: (2-x-y)SrOx(Ba, Ca)O (1-a-b-c-d)SiO2aP2O5bAl2O3cB2O3dGeO2: y Eu2+ and/or (2-x-y)BaOx((Sr, Ca)O (1-a-b-c-d)SiO2aP2O5bAl2O3cB2O3dGeO2: y Eu2+. The desired color (color temperature) can be easily adjusted by using a luminophore of the aforementioned type.
    Type: Grant
    Filed: August 4, 2006
    Date of Patent: August 21, 2007
    Assignee: Toyoda Gosei Co., Ltd.
    Inventors: Stefan Tasch, Peter Pachler, Gundula Roth, Walter Tews, Wolfgang Kempfert, Detlef Starick
  • Publication number: 20070090383
    Abstract: The light emitting device has a light emitting diode which is made of a nitride semiconductor and a phosphor which absorbs a part of lights emitted from the light emitting diode and emits different lights with wavelengths other than those of the absorbed lights. The phosphor is made of alkaline earth metal silicate fluorescent material activated with europium.
    Type: Application
    Filed: November 30, 2006
    Publication date: April 26, 2007
    Applicants: Toyoda Gosei Co., Ltd., Tridonic Optoelectronics GMBH, Litec GBR, Leuchstoffwerk Breitungen GMBH
    Inventors: Koichi Ota, Atsuo Hirano, Akihito Ota, Stefan Tasch, Peter Pachler, Gundula Roth, Walter Tews, Wolfgang Kempfert, Detlef Starick
  • Patent number: 7187011
    Abstract: The invention relates to a light source comprising a light-emitting element, which emits light in a first spectral region, and comprising a luminophore, which comes from the group of alkaline-earth orthosilicates and which absorbs a portion of the light emitted by the light source and emits light in another spectral region. According to the invention, the luminophore is an alkaline-earth orthosilicate, which is activated with bivalent europium and whose composition consists of: (2-x-y)SrOx(Ba, Ca)O (1-a-b-c-d)SiO2 aP2O5 bAl2O3 cB2O3 dGeO2: y Eu2+ and/or (2-x-y)BaO x((Sr, Ca)O (1-a-b-c-d)SiO2 aP2O5 bAl2O3 cB2O3 dGeO2: y Eu2+. The desired color (color temperature) can be easily adjusted by using a luminophore of the aforementioned type.
    Type: Grant
    Filed: October 26, 2004
    Date of Patent: March 6, 2007
    Assignee: Toyoda Gosei Co., Ltd.
    Inventors: Stefan Tasch, Peter Pachler, Gundula Roth, Walter Tews, Wolfgang Kempfert, Detlef Starick
  • Patent number: 7157746
    Abstract: The light emitting device has a light emitting diode which is made of a nitride semiconductor and a phosphor which absorbs a part of lights emitted from the light emitting diode and emits different lights with wavelengths other than those of the absorbed lights. The phosphor is made of alkaline earth metal silicate fluorescent material activated with europium.
    Type: Grant
    Filed: September 30, 2004
    Date of Patent: January 2, 2007
    Assignees: Toyoda Gosei Co., Ltd., Tridonic Optoelectronics GmbH, Litec GBR, Leuchstoffwerk Breitungen GmbH
    Inventors: Koichi Ota, Atsuo Hirano, Akihito Ota, Stefan Tasch, Peter Pachler, Gundula Roth, Walter Tews, Wolfgang Kempfert, Detlef Starick
  • Publication number: 20060267031
    Abstract: The invention relates to a light source comprising a light-emitting element, which emits light in a first spectral region, and comprising a luminophore, which comes from the group of alkaline-earth orthosilicates and which absorbs a portion of the light emitted by the light source and emits light in another spectral region. According to the invention, the luminophore is an alkaline-earth orthosilicate, which is activated with bivalent europium and whose composition consists of: (2-x-y)SrOx(Ba, Ca)O (1-a-b-c-d)SiO2aP2O5bAl2O3cB2O3dGeO2: y Eu2+ and/or (2-x-y)BaOx((Sr, Ca)O (1-a-b-c-d)SiO2aP2O5bAl2O3cB2O3dGeO2: y Eu2+. The desired color (color temperature) can be easily adjusted by using a luminophore of the aforementioned type.
    Type: Application
    Filed: August 4, 2006
    Publication date: November 30, 2006
    Inventors: Stefan Tasch, Peter Pachler, Gundula Roth, Walter Tews, Wolfgang Kempfert, Detlef Starick
  • Patent number: 7138660
    Abstract: The light emitting device has a light emitting diode which is made of a nitride semiconductor and a phosphor which absorbs a part of lights emitted from the light emitting diode and emits different lights with wavelengths other than those of the absorbed lights. The phosphor is made of alkaline earth metal silicate fluorescent material activated with europium.
    Type: Grant
    Filed: March 24, 2005
    Date of Patent: November 21, 2006
    Assignees: Toyoda Gosei Co., Ltd., Tridonic Optoelectronics GmbH, Litec GBR, Leuchstoffwerk Breitungen GmbH
    Inventors: Koichi Ota, Atsuo Hirano, Akihito Ota, Stefan Tasch, Peter Pachler, Gundula Roth, Walter Tews, Wolfgang Kempfert, Detlef Starick
  • Patent number: 6943380
    Abstract: The light emitting device has a light emitting diode which is made of a nitride semiconductor and a phosphor which absorbs a part of lights emitted from the light emitting diode and emits different lights with wavelengths other than those of the absorbed lights. The phosphor is made of alkaline earth metal silicate fluorescent material activated with europium.
    Type: Grant
    Filed: December 28, 2001
    Date of Patent: September 13, 2005
    Assignees: Toyoda Gosei Co., Ltd., Tridonic Optoelectronics GmbH, Litec GBR, Leuchstoffwerk Breitungen GmbH
    Inventors: Koichi Ota, Atsuo Hirano, Akihito Ota, Stefan Tasch, Peter Pachler, Gundula Roth, Walter Tews, Wolfgang Kempfert, Detlef Starick
  • Publication number: 20050162069
    Abstract: The light emitting device has a light emitting diode which is made of a nitride semiconductor and a phosphor which absorbs a part of lights emitted from the light emitting diode and emits different lights with wavelengths other than those of the absorbed lights. The phosphor is made of alkaline earth metal silicate fluorescent material activated with europium.
    Type: Application
    Filed: March 24, 2005
    Publication date: July 28, 2005
    Applicants: Toyoda Gosei Co., Ltd., Tridonic Optoelectronics GMBH, Litec GBR, Leuchstoffwerk Breitungen GMBH
    Inventors: Koichi Ota, Atsuo Hirano, Akihito Ota, Stefan Tasch, Peter Pachler, Gundula Roth, Walter Tews, Wolfgang Kempfert, Detlef Starick
  • Publication number: 20050082574
    Abstract: The invention relates to a light source comprising a light-emitting element, which emits light in a first spectral region, and comprising a luminophore, which comes from the group of alkaline-earth orthosilicates and which absorbs a portion of the light emitted by the light source and emits light in another spectral region. According to the invention, the luminophore is an alkaline-earth orthosilicate, which is activated with bivalent europium and whose composition consists of: (2-x-y)SrOx(Ba, Ca)O (1-a-b-c-d)SiO2 aP2O5 bAl2O3 cB2O3 dGeO2: y Eu2+ and/or (2-x-y)BaO x((Sr, Ca)O (1-a-b-c-d)SiO2 aP2O5 bAl2O3 cB2O3 dGeO2: y Eu2+. The desired color (color temperature) can be easily adjusted by using a luminophore of the aforementioned type.
    Type: Application
    Filed: October 26, 2004
    Publication date: April 21, 2005
    Inventors: Stefan Tasch, Peter Pachler, Gundula Roth, Walter Tews, Wolfgang Kempfert, Detlef Starick
  • Publication number: 20050077532
    Abstract: The light emitting device has a light emitting diode which is made of a nitride semiconductor and a phosphor which absorbs a part of lights emitted from the light emitting diode and emits different lights with wavelengths other than those of the absorbed lights. The phosphor is made of alkaline earth metal silicate fluorescent material activated with europium.
    Type: Application
    Filed: September 30, 2004
    Publication date: April 14, 2005
    Applicants: Toyoda Gosei Co., Ltd., Tridonic Optoelectronics GMBH, Litec GBR, Leuchstoffwerk Breitungen GMBH
    Inventors: Koichi Ota, Atsuo Hirano, Akihito Ota, Stefan Tasch, Peter Pachler, Gundula Roth, Walter Tews, Wolfgang Kempfert, Detlef Starick
  • Patent number: 6841092
    Abstract: The present invention provides a secured document including a composition capable of anti-Stokes fluorescence containing an ion capable of absorption of electromagnetic radiation, an ion capable of emitting electromagnetic radiation, and a matrix composition comprising gadolinium, yttrium, lanthanum, and lutetium, wherein the wavelength of the emitted electromagnetic radiation is shorter than the wavelength of the absorbed electromagnetic radiation, and wherein the concentrations of the absorbing and emitting ions are adjusted to achieve concentration quenching of anti-Stokes luminescence.
    Type: Grant
    Filed: March 18, 2002
    Date of Patent: January 11, 2005
    Assignees: Bundesdruckerei GmbH, Fa. Leuchtstoffwerk Breitungen GmbH
    Inventors: Manfred Paeschke, Benedikt Ahlers, Anett Bailleu, Oliver Muth, Arnim Franz-Burgholtz, Wolfgang Schmidt, Detlef Starick, Wolfgang Kempfert
  • Patent number: 6809347
    Abstract: The invention relates to a light source comprising a light-emitting element, which emits light in a first spectral region, and comprising a luminophore, which comes from the group of alkaline-earth orthosilicates and which absorbs a portion of the light emitted by the light source and emits light in another spectral region. According to the invention, the luminophore is an alkaline-earth orthosilicate, which is activated with bivalent europium and whose composition consists of: (2-x-y)SrOx(Ba, Ca)O(1-a-b-c-d)SiO2aP2O5bAl2O3cB2O3dGeO2:yEu2+ and/or (2-x-y)BaOx((Sr, Ca)O(1-a-b-c-d)SiO2aP2O5bAl2O3cB2O3dGeO2:yEu2+. The desired color (color temperature) can be easily adjusted by using a luminophore of the aforementioned type.
    Type: Grant
    Filed: December 22, 2003
    Date of Patent: October 26, 2004
    Assignees: Leuchtstoffwerk Breitungen GmbH, Tridonic Optoelectronics GmbH, Bitec GbR, Toyoda Gosei Co., Ltd.
    Inventors: Stefan Tasch, Peter Pachler, Gundula Roth, Walter Tews, Wolfgang Kempfert, Detlef Starick
  • Publication number: 20040090174
    Abstract: The invention relates to a light source comprising a light-emitting element, which emits light in a first spectral region, and comprising a luminophore, which comes from the group of alkaline-earth orthosilicates and which absorbs a portion of the light emitted by the light source and emits light in another spectral region. According to the invention, the luminophore is an alkaline-earth orthosilicate, which is activated with bivalent europium and whose composition consists of: (2-x-y)SrOx(Ba, Ca)O(1-a-b-c-d)SiO2aP2O5bAl2O3cB2O3dGeO2:yEu2+ and/or (2-x-y)BaOx((Sr, Ca)O(1-a-b-c-d)SiO2aP2O5bAl2O3cB2O3dGeO2:yEu2+. The desired color (color temperature) can be easily adjusted by using a luminophore of the aforementioned type.
    Type: Application
    Filed: December 22, 2003
    Publication date: May 13, 2004
    Inventors: Stefan Tasch, Peter Pachler, Gundula Roth, Walter Tews, Wolfgang Kempfert, Detlef Starick
  • Publication number: 20040051111
    Abstract: The light emitting device has a light emitting diode which is made of a nitride semiconductor and a phosphor which absorbs a part of lights emitted from the light emitting diode and emits different lights with wavelengths other than those of the absorbed lights. The phosphor is made of alkaline earth metal silicate fluorescent material activated with europium.
    Type: Application
    Filed: June 30, 2003
    Publication date: March 18, 2004
    Inventors: Koichi Ota, Atsuo Hirano, Akihito Ota, Stefan Tasch, Peter Pachler, Gundula Roth, Walter Tews, Wolfgang Kempfert, Detlef Starick
  • Publication number: 20020130304
    Abstract: The present invention provides a secured document including a composition capable of anti-Stokes fluorescence containing an ion capable of absorption of electromagnetic radiation, an ion capable of emitting electromagnetic radiation, and a matrix composition comprising gadolinium, yttrium, lanthanum, and lutetium, wherein the wavelength of the emitted electromagnetic radiation is shorter than the wavelength of the absorbed electromagnetic radiation, and wherein the concentrations of the absorbing and emitting ions are adjusted to achieve concentration quenching of anti-Stokes luminescence.
    Type: Application
    Filed: March 18, 2002
    Publication date: September 19, 2002
    Applicant: Bundesdruckerei GmbH and Fa. Leuchtstoffwerk Breitungen GmbH
    Inventors: Manfred Paeschke, Benedikt Ahlers, Anett Bailleu, Oliver Muth, Arnim Franz-Burgholtz, Wolfgang Schmidt, Detlef Starick, Wolfgang Kempfert