Nano-patterning boosts LED efficiency (MAGAZINE)
A variety of nano-patterning technologies can be used to enhance the light-extraction efficiency of LED chips, according to Ki Dong Lee, Robert Sjodin, and Torbjorn Eriksson.
LED efficiency measures the final light output for a given electrical input, and is determined by four factors: internal quantum efficiency, extraction efficiency, electrical efficiency and package efficiency. Internal quantum efficiency measures how many photons can be generated for given electron-hole pair generation, and is determined mostly by the quality of the epitaxial layer. Lightextraction efficiency defines how many photons of those generated can escape the LED device, and is determined by the chip and package structure.
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