- Oct 20, 2017 -
The presence of incompatible volatile organic compounds (VOCs) in LED-based solid state lighting (SSL) designs can impair the performance and reduce the lifetime of these illumination systems. Glues, conformal coatings, O-rings, gaskets, and potting compounds are materials frequently used in the construction of LED-based luminaires or lamps and often contain VOCs. The presence of chemically incompatible VOCs on or near LEDs can degrade the light output levels or cause changes in the chromaticity point of the light. The photograph in Figure 1 above is an example of this VOC degradation on the surface of an LED. This sensitivity to VOCs is not unique to one LED manufacturer but is a known problem for all types of blue, royal blue and white-light LEDs. Chemical incompatibility in SSL is often a localized phenomenon, occurring in luminaire designs that seal portions of the system, resulting in an LED operating environment having elevated temperatures with little or no air movement. However, with proper design and adequate testing, chemical incompatibility effects can be prevented.