Tunable natural light realized by phosphor-innovation light-emitting-diode technology

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Abstract

The nature and quality of artificial lighting are becoming more and more recognized and debated issues concerning their impact on comfort, well-being and even human’s health (chronobiology). Therefore, the target must be to emulate natural (sun) light for indoor illumination. In this paper parameters which are responsible for the nature and quality of light sources are elaborated. Leading edge high quality light sources, realized by light emitting diodes (LEDs) for emulating natural light, are presented.

The junction temperature of electroluminescence devices is a key parameter which influences emission wavelength, light output (power efficiency), light degradation and lifetime of the LEDs. We present experimental data and a model which allows one to derive the junction temperature of LEDs under operation.

Keywords

light emitting diodes PI-LED natural light junction temperature white light emitter chronobiology 

Veränderbares natürliches Licht realisiert mit Phosphor-Innovation Licht-Emittierender-Dioden-Technologie

Zusammenfassung

Die Natur und die Qualität künstlicher Lichtquellen und deren Auswirkungen auf Komfort, Wohlbefinden und Gesundheit werden immer stärker wahrgenommen und diskutiert (Chronobiologie). Daraus folgt nahezu zwingend die Forderung, natürliches (Sonnen-)Licht im Bereich der Innenraumbeleuchtung nachzubilden. In dieser Arbeit werden wesentliche Parameter, welche die Natur und die Qualität von Lichtquellen bestimmen, behandelt. Präsentiert werden technologisch führende und hoch qualitative Lichtquellen zur Erzeugung von „natürlichem“ Licht unter Verwendung von Licht emittierenden Dioden (LEDs).

Die Temperatur der Grenzschicht ist ein Schlüsselparameter, der die Emissionswellenlänge, die Lichtausbeute (Effizienz), die Lichtdegradation und letztlich die Lebensdauer von LEDs bestimmt. Wir präsentieren Messergebnisse zur Grenzschichttemperatur und ein Modell, welches erlaubt, die Temperatur der Grenzschicht der LED im Betrieb zu bestimmen.

Schlüsselwörter

Licht emittierende Dioden PI-LED Natürliches Licht Grenzschichttemperatur Weißlicht-Emitter Chronobiologie 

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Copyright information

© Springer-Verlag Wien 2012

Authors and Affiliations

  • Reinhold Hetzel
    • 1
    • 2
  • Stefan Tasch
    • 2
  • Günther Leising
    • 1
  1. 1.Institute of Solid State PhysicsGraz University of TechnologyGrazAustria
  2. 2.LUMITECH Produktion und Entwicklung GmbHJennersdorfAustria

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