Highly efficient all-nitride phosphor-converted white light emitting diode
Regina Mueller-Mach
Lumileds Lighting U.S., LLC, 370 West Trimble Road, MS 91UK, San Jose, CA 95131, USA
Search for more papers by this authorGerd Mueller
Lumileds Lighting U.S., LLC, 370 West Trimble Road, MS 91UK, San Jose, CA 95131, USA
Search for more papers by this authorMichael R. Krames
Lumileds Lighting U.S., LLC, 370 West Trimble Road, MS 91UK, San Jose, CA 95131, USA
Search for more papers by this authorHenning A. Höppe
Institute of Inorganic and Analytic Chemistry, University of Freiburg, Albertstr. 21, 79104 Freiburg, Germany
Search for more papers by this authorFlorian Stadler
Department of Chemistry and Biochemistry, University of Munich (LMU), Butenandtstr. 5–13, 81377 Munich, Germany
Search for more papers by this authorCorresponding Author
Wolfgang Schnick
Department of Chemistry and Biochemistry, University of Munich (LMU), Butenandtstr. 5–13, 81377 Munich, Germany
Phone: +49 89 2180 77436, Fax: +49 89 2180 77440Search for more papers by this authorThomas Juestel
University of Applied Sciences Muenster, Stegerwaldstr. 39, 48565 Steinfurt, Germany
Search for more papers by this authorPeter Schmidt
Philips Research Laboratories Aachen, Weisshausstr. 2, 52066 Aachen, Germany
Search for more papers by this authorRegina Mueller-Mach
Lumileds Lighting U.S., LLC, 370 West Trimble Road, MS 91UK, San Jose, CA 95131, USA
Search for more papers by this authorGerd Mueller
Lumileds Lighting U.S., LLC, 370 West Trimble Road, MS 91UK, San Jose, CA 95131, USA
Search for more papers by this authorMichael R. Krames
Lumileds Lighting U.S., LLC, 370 West Trimble Road, MS 91UK, San Jose, CA 95131, USA
Search for more papers by this authorHenning A. Höppe
Institute of Inorganic and Analytic Chemistry, University of Freiburg, Albertstr. 21, 79104 Freiburg, Germany
Search for more papers by this authorFlorian Stadler
Department of Chemistry and Biochemistry, University of Munich (LMU), Butenandtstr. 5–13, 81377 Munich, Germany
Search for more papers by this authorCorresponding Author
Wolfgang Schnick
Department of Chemistry and Biochemistry, University of Munich (LMU), Butenandtstr. 5–13, 81377 Munich, Germany
Phone: +49 89 2180 77436, Fax: +49 89 2180 77440Search for more papers by this authorThomas Juestel
University of Applied Sciences Muenster, Stegerwaldstr. 39, 48565 Steinfurt, Germany
Search for more papers by this authorPeter Schmidt
Philips Research Laboratories Aachen, Weisshausstr. 2, 52066 Aachen, Germany
Search for more papers by this authorAbstract
The development and demonstration of a highly efficient warm-white all-nitride phosphor-converted light emitting diode (pc-LED) is presented utilizing a GaN based quantum well blue LED and two novel nitrogen containing luminescent materials, both of which are doped with Eu2+. For color conversion of the primary blue the nitridosilicates M2Si5N8 (orange-red) and MSi2O2N2 (yellow-green), with M = alkaline earth, were employed, thus achieving a high luminous efficiency (25 lumen/W at 1 W input), excellent color quality (correlated color temperature CCT = 3200 K, general color rendering index Ra > 90) and the highest proven color stability of any pc-LED obtained so far. Thus, these novel all-nitride LEDs are superior to both incandescent and fluorescent lamps and may therefore become the next generation of general lighting sources. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
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