A novel application of green (La, Ce, Tb)PO4:Ce:Tb phosphor on the luminous efficacy and color quality of white LEDs

Abstract

In this paper, we propose a method to enhance luminous efficacy and color quality of the multi-chip white LED lamps (MCW-LEDs) at high color correlated temperature. This can be done by the incorporation (La, Ce, Tb)PO4:Ce:Tb green phosphor (LaTb) with YAG:Ce yellow phosphor compounding. Index, the employment this green phosphor into MCW-LEDs could bring a great effect on the optical performance of MCW-LEDs. Simulation results demonstrated that the optical properties at temperature of 8500K significantly improve with a size range from 1–10 μm and the LaTb concentration from 0–1.8%, while the color quality scale (CQS) slightly decreases. With the proper choice of LaTb particle size range around 6–8 μm and the concentration around 1.5%, the optimal lumen output and color quality of MCW-LEDs can be achieved.