Abstract

This paper reports on an extensive analysis of the degradation of remote phosphors for solid-state lighting applications. The study is based on combined optical and thermal measurements, carried out before and during long-term stress tests, and provides the following results: 1) During normal operation, phosphors can show significant self-heating; 2) as a consequence of self-heating, the conversion efficiency of the phosphors decreases; and 3) exposure to long-term stress tests at moderate/high temperature levels (in the range of 85 °C-145 °C) can lead to remarkable degradation of the phosphors. Degradation mainly consists in a decrease in conversion efficiency and in worsening of the chromatic properties of the light-emitting diode-phosphor system. Finally, an activation energy value of 1.2 eV was extrapolated for the thermally activated degradation of the phosphors.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.