Patents by Inventor Prasanth Kumar Nammalwar
Prasanth Kumar Nammalwar 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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Patent number: 11851595Abstract: A lighting apparatus includes a semiconductor light source in direct contact with a polymer composite comprising a color stable Mn4+ doped phosphor, wherein the lighting apparatus has a color shift of ?1.5 MacAdam ellipses after operating for at least 2,000 hour at a LED current density greater than 2 A/cm2, a LED wall-plug efficiency greater than 40%, and a board temperature greater than 25° C.Type: GrantFiled: July 13, 2021Date of Patent: December 26, 2023Assignee: CURRENT LIGHTING SOLUTIONS, LLCInventors: James Edward Murphy, Anant Achyut Setlur, Florencio Garcia, Robert Joseph Lyons, Ashfaqul Islam Chowdhury, Nagaveni Karkada, Prasanth Kumar Nammalwar, William Winder Beers
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Publication number: 20210340443Abstract: A lighting apparatus includes a semiconductor light source in direct contact with a polymer composite comprising a color stable Mn4+ doped phosphor, wherein the lighting apparatus has a color shift of ?1.5 MacAdam ellipses after operating for at least 2,000 hour at a LED current density greater than 2 A/cm2, a LED wall-plug efficiency greater than 40%, and a board temperature greater than 25° C.Type: ApplicationFiled: July 13, 2021Publication date: November 4, 2021Inventors: James Edward MURPHY, Anant Achyut SETLUR, Florencio GARCIA, Robert Joseph LYONS, Ashfaqul Islam CHOWDHURY, Nagaveni KARKADA, Prasanth Kumar NAMMALWAR, William Winder BEERS
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Patent number: 11149195Abstract: A process for coating a phosphor of formula I: Ax[MFy]:Mn4+ includes combining the phosphor of formula I in particulate form with a first solution including a compound of formula II: Ax[MFy] to form a suspension and combining a second solution with the suspension, the second solution including a precursor including an element selected from the group consisting of calcium, strontium, magnesium, yittrium, barium, scandium, lanthanum, and combinations thereof. A population of particles having a core including a phosphor of formula I and a manganese-free composite coating disposed on the core, and a lighting apparatus (10) including the population of particles are also presented.Type: GrantFiled: November 15, 2017Date of Patent: October 19, 2021Assignee: CURRENT LIGHTING SOLUTIONS, LLCInventors: Digamber Gurudas Porob, Prasanth Kumar Nammalwar, Srinidhi Ramachandra, Matthew David Butts, James Edward Murphy
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Patent number: 11098246Abstract: A lighting apparatus includes a semiconductor light source in direct contact with a polymer composite comprising a color stable Mn4+ doped phosphor, wherein the lighting apparatus has a color shift of ?1.5 MacAdam ellipses after operating for at least 2,000 hour at a LED current density greater than 2 A/cm2, a LED wall-plug efficiency greater than 40%, and a board temperature greater than 25° C.Type: GrantFiled: March 6, 2019Date of Patent: August 24, 2021Assignee: CURRENT LIGHTING SOLUTIONS, LLCInventors: James Edward Murphy, Anant Achyut Setlur, Florencio Garcia, Robert Joseph Lyons, Ashfaqul Islam Chowdhury, Nagaveni Karkada, Prasanth Kumar Nammalwar, William Winder Beers
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Patent number: 10920136Abstract: A process for synthesizing a manganese doped phosphor of formula I: Ax [MFy]:Mn4+ is presented. The process includes contacting a first solution with a second solution and a third solution in the presence of a plurality of inert particles. The first solution and the second solution include a composition of formula II: Ax[MnFy]. The third solution includes a source of M, where A is Li, Na, K, Rb, Cs, or combinations thereof; M is Si, Ge, Sn, Ti, Zr, Al, Ga, In, Sc, Hf, Y, La, Nb, Ta, Bi, Gd, or combinations thereof; x is an absolute value of a charge of the [MFy] ion; and y is 5, 6 or 7.Type: GrantFiled: October 18, 2016Date of Patent: February 16, 2021Assignee: CURRENT LIGHTING SOLUTIONS, LLCInventors: Ravikumar Hanumantha, Prasanth Kumar Nammalwar, Digamber Gurudas Porob
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Patent number: 10815423Abstract: A process for synthesizing a Mn4+ doped phosphor of formula I by electrolysis is presented. The process includes electrolyzing a reaction solution comprising a source of manganese, a source of M and a source of A. One aspect relates to a phosphor composition produced by the process. A lighting apparatus including the phosphor composition is also provided. Ax[MFy]:Mn4+ (I) where, A is Li, Na, K, Rb, Cs, or a combination thereof; M is Si, Ge, Sn, Ti, Zr, Al, Ga, In, Sc, Hf, Y, La, Nb, Ta, Bi, Gd, or a combination thereof; x is the absolute value of the charge of the [MFy] ion; and y is 5, 6 or 7.Type: GrantFiled: March 2, 2016Date of Patent: October 27, 2020Assignee: CURRENT LIGHTING SOLUTIONS, LLCInventors: Digamber Gurudas Porob, Anant Achyut Setler, Prasanth Kumar Nammalwar, James Edward Murphy
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Patent number: 10620324Abstract: A method and an apparatus for detecting photons are disclosed. The apparatus includes a scintillator single crystal and an avalanche photodiode coupled to the scintillator single crystal. The scintillator single crystal is at a temperature greater than about 175° C. and at a shock level in a range from about 20 Grms to about 30 Grms. The scintillator single crystal includes a praseodymium doped composition selected from (LaxY1-x)2Si2O7:Pr, ABCl3-yXy:Pr, A2(Li,Na)LaCl6-yXy:Pr, or any combinations thereof. As used herein A is cesium, rubidium, potassium, sodium, or a combination thereof, B is calcium, barium, strontium, magnesium, cadmium, zinc, or a combination thereof, and X is bromine, iodine, or a combination thereof. Further, (0<x<1), and (0<y<3).Type: GrantFiled: May 14, 2015Date of Patent: April 14, 2020Assignee: Baker Hughes Oilfield Operations, LLCInventors: Srinidhi Ramachandra, Wusheng Xu, Alok Mani Srivastava, Gopi Chandran Ramachandran, Prasanth Kumar Nammalwar, Sergei Ivanovich Dolinsky, Helene Claire Climent
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Publication number: 20190292448Abstract: A process for coating a phosphor of formula I: Ax[MFy]:Mn4+ includes combining the phosphor of formula I in particulate form with a first solution including a compound of formula II: Ax[MFy] to form a suspension and combining a second solution with the suspension, the second solution including a precursor including an element selected from the group consisting of calcium, strontium, magnesium, yittrium, barium, scandium, lanthanum, and combinations thereof. A population of particles having a core including a phosphor of formula I and a manganese-free composite coating disposed on the core, and a lighting apparatus (10) including the population of particles are also presented.Type: ApplicationFiled: November 15, 2017Publication date: September 26, 2019Inventors: Digamber Gurudas POROB, Prasanth Kumar NAMMALWAR, Srinidhi RAMACHANDRA, Matthew David BUTTS, James Edward MURPHY
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Publication number: 20190203116Abstract: A lighting apparatus includes a semiconductor light source in direct contact with a polymer composite comprising a color stable Mn4+ doped phosphor, wherein the lighting apparatus has a color shift of ?1.5 MacAdam ellipses after operating for at least 2,000 hour at a LED current density greater than 2 A/cm2, a LED wall-plug efficiency greater than 40%, and a board temperature greater than 25° C.Type: ApplicationFiled: March 6, 2019Publication date: July 4, 2019Inventors: James Edward MURPHY, Anant Achyut SETLUR, Florencio GARCIA, Robert Joseph LYONS, Ashfaqul Islam CHOWDHURY, Nagaveni KARKADA, Prasanth Kumar NAMMALWAR, William Winder BEERS
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Patent number: 10131835Abstract: A phosphor composition is derived from combining K2SiF6:Mn4+ in solid form with a saturated solution of a manganese-free complex fluoride including a composition of formula I: A3[MF6], where A is selected from Na, K, Rb, and combinations thereof and M is selected from Al, Ga, In, Sc, Y, Gd, and combinations thereof. The composition of formula I: A3[MF6] has a water solubility lower than a water solubility of K2SiF6. A lighting apparatus including the phosphor composition is also provided.Type: GrantFiled: December 16, 2014Date of Patent: November 20, 2018Assignee: General Electric CompanyInventors: Anant Achyut Setlur, Robert Joseph Lyons, Prasanth Kumar Nammalwar, James Edward Murphy, Florencio Garcia, Ravikumar Hanumantha
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Publication number: 20180312751Abstract: A process for synthesizing a manganese doped phosphor of formula I: Ax [MFy]:Mn4+ is presented. The process includes contacting a first solution with a second solution and a third solution in the presence of a plurality of inert particles. The first solution and the second solution include a composition of formula II: Ax[MnFy]. The third solution includes a source of M, where A is Li, Na, K, Rb, Cs, or combinations thereof; M is Si, Ge, Sn, Ti, Zr, Al, Ga, In, Sc, Hf, Y, La, Nb, Ta, Bi, Gd, or combinations thereof; x is an absolute value of a charge of the [MFy] ion; and y is 5, 6 or 7.Type: ApplicationFiled: October 18, 2016Publication date: November 1, 2018Inventors: Ravikumar HANUMANTHA, Prasanth Kumar NAMMALWAR, Digamber Gurudas POROB
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Publication number: 20180051207Abstract: A process for synthesizing a Mn4+ doped phosphor of formula I by electrolysis is presented. The process includes electrolyzing a reaction solution comprising a source of manganese, a source of M and a source of A. One aspect relates to a phosphor composition produced by the process. A lighting apparatus including the phosphor composition is also provided. Ax[MFy]:Mn4+ (I) where, A is Li, Na, K, Rb, Cs, or a combination thereof; M is Si, Ge, Sn, Ti, Zr, Al, Ga, In, Sc, Hf, Y, La, Nb, Ta, Bi, Gd, or a combination thereof; x is the absolute value of the charge of the [MFy] ion; and y is 5, 6 or 7.Type: ApplicationFiled: March 2, 2016Publication date: February 22, 2018Inventors: Digamber Gurudas POROB, Anant Achyut SETLER, Prasanth Kumar NAMMALWAR, James Edward MURPHY
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Patent number: 9698314Abstract: A process for synthesizing a color stable Mn4+ doped phosphor includes contacting a precursor of formula I, in gaseous form at an elevated temperature with a fluorine-containing oxidizing agent to form the color stable Mn4+ doped phosphor Ax[MFy]:Mn4+??I wherein A is Li, Na, K, Rb, Cs, NR4 or a combination thereof; M is Si, Ge, Sn, Ti, Zr, Al, Ga, In, Sc, Hf, Y, La, Nb, Ta, Bi, Gd, or a combination thereof; R is H, lower alkyl, or a combination thereof; x is the absolute value of the charge of the [MFy] ion; and y is 5, 6 or 7.Type: GrantFiled: March 13, 2014Date of Patent: July 4, 2017Assignee: General Electric CompanyInventors: James Edward Murphy, Anant Achyut Setlur, Florencio Garcia, Robert Joseph Lyons, Ashfaqul Islam Chowdhury, Nagaveni Karkada, Prasanth Kumar Nammalwar
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Publication number: 20170145304Abstract: A lighting apparatus includes a semiconductor light source in direct contact with a polymer composite comprising a color stable Mn4+ doped phosphor, wherein the lighting apparatus has a color shift of 1.5 MacAdam ellipses after operating for at least 2,000 hour at a LED current density greater than 2 A/cm2, a LED wall-plug efficiency greater than 40%, and a board temperature greater than 25° C.Type: ApplicationFiled: January 10, 2017Publication date: May 25, 2017Inventors: James Edward Murphy, Anant Achyut Setlur, Florencio Garcia, Robert Joseph Lyons, Ashfaqul Islam Chowdhury, Nagaveni Karkada, Prasanth Kumar Nammalwar, William Winder Beers
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Publication number: 20170097426Abstract: A method and an apparatus for detecting photons are disclosed. The apparatus includes a scintillator single crystal and an avalanche photodiode coupled to the scintillator single crystal. The scintillator single crystal is at a temperature greater than about 175° C. and at a shock level in a range from about 20 Grms to about 30 Grms. The scintillator single crystal includes a praseodymium doped composition selected from (LaxY1-x)2Si2O7:Pr, ABCl3-yXy:Pr, A2(Li, Na)LaCl6-yXy:Pr, or any combinations thereof. As used herein A is cesium, rubidium, potassium, sodium, or a combination thereof, B is calcium, barium, strontium, magnesium, cadmium, zinc, or a combination thereof, and X is bromine, iodine, or a combination thereof. Further, (0<x<1), and (0<y<3).Type: ApplicationFiled: May 14, 2015Publication date: April 6, 2017Inventors: Srinidhi RAMACHANDRA, Wusheng XU, Alok Mani SRIVASTAVA, Gopi Chandran RAMACHANDRAN, Prasanth Kumar NAMMALWAR, Sergei Ivanovich DOLINSKY, Helene Claire CLIMENT
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Patent number: 9611237Abstract: A phosphor material is presented that includes a blend of a first phosphor, a second phosphor and a third phosphor. The first phosphor includes a composition having a general formula of RE2?yM1+yA2?yScySin?wGewO12+?:Ce3+ wherein RE is selected from a lanthanide ion or Y3+, where M is selected from Mg, Ca, Sr or Ba, A is selected from Mg or Zn and where 0?y?2, 2.5?n?3.5, 0?w?1, and ?1.5???1.5. The second phosphor includes a complex fluoride doped with manganese (Mn4+), and the third phosphor include a phosphor composition having an emission peak in a range from about 520 nanometers to about 680 nanometers. A lighting apparatus including such a phosphor material is also presented. The light apparatus includes a light source in addition to the phosphor material.Type: GrantFiled: September 20, 2012Date of Patent: April 4, 2017Assignee: GENERAL ELECTRIC COMPANYInventors: Prasanth Kumar Nammalwar, Digamber Gurudas Porob, Anant Achyut Setlur, Satya Kishore Manepalli
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Patent number: 9580648Abstract: A color stable Mn4+ doped phosphor of formula I, Ax[MFy]:Mn4+??I wherein A is Li, Na, K, Rb, Cs, or a combination thereof; M is Si, Ge, Sn, Ti, Zr, Al, Ga, In, Sc, Hf, Y, La, Nb, Ta, Bi, Gd, or a combination thereof; x is the absolute value of the charge of the [MFy] ion; y is 5, 6 or 7; and wherein % intensity loss of the phosphor after exposure to light flux of at least 80 w/cm2 at a temperature of at least 50° C. for at least 21 hours is ?4%.Type: GrantFiled: May 23, 2014Date of Patent: February 28, 2017Assignee: General Electric CompanyInventors: James Edward Murphy, Anant Achyut Setlur, Florencio Garcia, Robert Joseph Lyons, Ashfaqul Islam Chowdhury, Nagaveni Karkada, Prasanth Kumar Nammalwar
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Publication number: 20160376499Abstract: A phosphor composition is derived from combining K2SiF6:Mn4+ in solid form with a saturated solution of a manganese-free complex fluoride including a composition of formula I:A3[MF6], where A is selected from Na, K, Rb, and combinations thereof and M is selected from Al, Ga, In, Sc, Y, Gd, and combinations thereof. The composition of formula I:A3[MF6] has a water solubility lower than a water solubility of K2SiF6. A lighting apparatus including the phosphor composition is also provided.Type: ApplicationFiled: December 16, 2014Publication date: December 29, 2016Inventors: Anant Achyut Setlur, Robert Joseph Lyons, Prasanth Kumar Nammalwar, James Edward Murphy, Florencio Garcia, Ravikumar Hanumantha
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Patent number: 8906724Abstract: A process for synthesizing a color stable Mn4+ doped phosphor includes contacting a precursor of formula I, in gaseous form at an elevated temperature with a fluorine-containing oxidizing agent to form the color stable Mn4+ doped phosphor Ax[MFy]:Mn4+??I wherein A is Li, Na, K, Rb, Cs, or a combination thereof; M is Si, Ge, Sn, Ti, Zr, Al, Ga, In, Sc, Hf, Y, La, Nb, Ta, Bi, Gd, or a combination thereof; x is the absolute value of the charge of the [MFy] ion; and y is 5, 6 or 7.Type: GrantFiled: June 23, 2014Date of Patent: December 9, 2014Assignee: General Electric CompanyInventors: James Edward Murphy, Anant Achyut Setlur, Florencio Garcia, Robert Joseph Lyons, Ashfaqul Islam Chowdhury, Nagaveni Karkada, Prasanth Kumar Nammalwar
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Publication number: 20140327026Abstract: A process for synthesizing a color stable Mn4+ doped phosphor includes contacting a precursor of formula I, in gaseous form at an elevated temperature with a fluorine-containing oxidizing agent to form the color stable Mn4+ doped phosphor Ax[MFy]:Mn4+ wherein A is Li, Na, K, Rb, Cs, or a combination thereof; M is Si, Ge, Sn, Ti, Zr, Al, Ga, In, Sc, Hf, Y, La, Nb, Ta, Bi, Gd, or a combination thereof; x is the absolute value of the charge of the [MFy] ion; and y is 5, 6 or 7.Type: ApplicationFiled: June 23, 2014Publication date: November 6, 2014Inventors: James Edward Murphy, Anant Achyut Setlur, Florencio Garcia, Robert Joseph Lyons, Ashfaqul Islam Chowdhury, Nagaveni Karkada, Prasanth Kumar Nammalwar