Park Hoo Keun, Oh Jeong Rok, Do Young Rag
Department of Chemistry, Kookmin University, Seoul 136-702, Korea.
Opt Express. 2011 Dec 5;19(25):25593-601. doi: 10.1364/OE.19.025593.
This paper reports the optical effects of a two-dimensional (2D) SiNx photonic crystal layer (PCL) on Y3Al5O12:Ce3+ (YAG:Ce) yellow ceramic plate phosphor (CPP) in order to enhance the forward emission of YAG:Ce CPP-capped high-power white light-emitting diodes (LEDs). By adding the 2D SiNx PCL with a 580 nm lattice constant, integrated yellow emission was improved by a factor of 1.72 compared to that of a conventional YAG:Ce CPP capped on a blue LED cup. This enhanced forward yellow emission is attributed to increased extraction of yellow emission light and improved absorption of blue excitation light through Bragg scattering and/or the leaky modes produced by the 2D PCLs. The introduction of 2D PCL can also reduce the wide variation of optical properties as a function of both ambient temperature and applied current, compared to those of a high-power YAG:Ce CPP-capped LED.
本文报道了二维（2D）SiNx光子晶体层（PCL）对Y3Al5O12:Ce3+（YAG:Ce）黄色陶瓷板荧光粉（CPP）的光学效应，以增强YAG:Ce CPP封装的高功率白光发光二极管（LED）的正向发射。通过添加晶格常数为580 nm的2D SiNx PCL，与封装在蓝色LED杯上的传统YAG:Ce CPP相比，黄色发射积分提高了1.72倍。这种增强的正向黄色发射归因于通过布拉格散射和/或2D PCL产生的泄漏模式增加了黄色发射光的提取以及提高了蓝色激发光的吸收。与高功率YAG:Ce CPP封装的LED相比，引入2D PCL还可以减少光学性能随环境温度和施加电流的宽范围变化。
