Full Extraction of 2D Photonic Crystal Assisted $ \hbox{Y}_{3}\hbox{Al}_{5}\hbox{O}_{12}$:Ce Ceramic Plate Phosphor for Highly Efficient White LEDs

Abstract

In this paper, we report the optical and thermal effects of filling the air gap between a ceramic plate phosphor (CPP) and a cup-type light-emitting diode (LED) in a white phosphor-converted LED (pc-LED) package. The aim of our work was to improve extraction efficiency fully, as well as to enhance heat dissipation; and in this case, the CPP was a two-dimensional (2D) TiO2 nanobowl photonic crystal layer (PCL)-assisted Y3Al5O12: Ce3 +(YAG: Ce). By adding a 2D TiO2 PCL and eliminating the air gap between the CPP and the LED cup, our package exhibited better luminous efficacy, more uniform optical properties, and higher thermal conductivity than those of a 2D TiO2 PCL-assisted CPP-capped LED with an air gap and a conventional phosphor powder dispersed in an LED package.