Fabrication, optical and luminescence properties of low pressure injection molded YAG:Ce tubular ceramics for outdoor lighting

Elaborating a high performance and thermostable LED lighting source based on YAG:Ce ceramic photo-convertor is mainstream for outdoor lighting. However, it still suffers from narrow luminous angle using traditional molding method. In this paper, high quality YAG:Ce tubular ceramic was prepared using a low pressure injection molding (LPIM) and vacuum sintering. The results showed the viscosity of suspension with 75.0 wt.% solid content was as low as 190.34 Pa?s at the shear rate of 100 (s-1), and the molding pressure and holding time were adopted to be 0.8 MPa and 8 s, respectively. Impressively, the final YAG:Ce ceramic (double polished to 1.0 mm) with relatively high in-line transmittance of 72.5 % was produced. Furthermore, constructing the YAG:Ce ceramic tube with the hexahedral columnar blue chip arrays, a 4 pi white light emission with a luminous efficiency of 126.46 lm/W and low correlated-color temperature of 4333 K and was attained.

Automated summary

This study demonstrates the fabrication of high quality YAG:Ce ceramic using LPIM and vacuum sintering methods, achieving high luminous efficiency for LED lighting. By constructing a unique blue chip array, a 4π white light emission with high efficiency is achieved.