White LED light fades What factors influence Traditional packaged white LED, fluorescent plastic commonly used epoxy or silicone, after the light fades experimental results obtained with silica powder with white LED life is significantly longer than the epoxy. One reason is to use the above two methods into a finished packaged LED, UV-resistant silicone resin ratio and the strong cooling effect than the silicone resin is good; but under the same conditions, with the initial brightness of silica than with epoxy powder resin with powder to be low, the most important is the refractive index of silica gel (1.3-1.4) than the epoxy resin (1.5) is low, so the initial high light efficiency is less than epoxy. White LED to achieve a variety of ways, and is currently the most widely used one is the most mature in the blue chip on the smear layer of yellow phosphor, the blue and yellow mixed into white, so white LED phosphor material on the attenuation influence. Most mainstream market YAG phosphor is yttrium aluminum garnet phosphors, phosphor silicate nitride phosphor, compared with the blue LED chip white LED phosphor has the role of accelerated aging, and different manufacturers phosphor light failure is not the same degree of influence, which is closely related to the phosphor raw ingredients. Lehman photoelectric choose the best material white phosphor, so make white LED compared to peers in the attenuation control has been greatly improved. Currently white LED lighting has become the general household lighting has become a reality. But in the course of more white products attenuation, not suitable for the lighting market, Lehman photoelectric lighting for the high-end market demand, increase the development of white light by changing the packaging technology and materials with low attenuation white products developed for LED lighting industry to do a little modest.
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