Title :
Uniform White Emission of WLEDs Realized by Multilayer Phosphor With Pyramidal Shape and Inversed Concentration Distribution
Author :
Liu, Zong-Yuan ; Li, Cheng ; Yu, Bin-Hai ; Wang, Yao-Hao ; Niu, Han-Ben
Author_Institution :
Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, Shenzhen University, Shenzhen, China
Abstract :
The effect of pyramidal multilayer phosphor layout on the color uniformity of white light-emitting diodes is analyzed, using the Monte Carlo ray-tracing optical simulation. The color uniformity has been improved by tailoring the number of layers, the pyramidal shape, and the phosphor concentration distribution. Results show that Layout C, with five layers and a three step inversed concentration distribution, can realize a much more uniform white emission with an angular color variation of 55 K and an angular color uniformity of 99.17%.
Keywords :
Color; Integrated circuits; Integrated optics; Layout; Light emitting diodes; Phosphors; Shape; Color uniformity; concentration; light-emitting diodes (LEDs); packaging; phosphor;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2012.2209200
