High-efficiency phosphor-in-glass with ultra-high color rendering indexing for white laser diode lighting

• DOI: 10.1016/j.ceramint.2021.09.247
• Publication Date: 2021-09-27T08:16:55Z
• Authors: Jiangdan Zhang; Liansheng Wang; Fucai Xu; Luhan Wang; Li Xu; Qiangqiang Zhu; Xiaojuan Liang; Weidong Xiang
• Keywords: Color rendering index; Luminous efficacy; Color temperature; Luminous flux; High color; LED lamp

Abstract Stable color converters exhibiting high color rendering index have drawn researchers’ attention for their applications in high-quality white laser lighting. In this study, we develop the multi-color phosphor-in-glass (PIG) with the weight ratio of green-emitting (Y3Al3.08Ga1.92O12:Ce3+) to red-emitting (CaAlSiN3:Eu2+) phosphor powders (10/1–18/1) by low temperature co-sintering method. The obtained composite material displays an outstanding optical and thermal performance, including a high internal quantum efficiency of 84.2%, a high transparency of 45% in the visible region and a low thermal quenching (it remains 86% at 448 K). By integrating 450 nm blue laser diodes with optimized multi-color PIG, the white light with a maximum luminous flux of 258 lm and a luminous efficiency of 137 lm/W is achieved for the first time. Additionally, considering the white balance, by tailoring the weight ratio of green-emitting to red-emitting phosphor and the thickness of PIG, the 14/1 PIG at fixed thickness of 0.75 mm produces pure white light with ultra-high color rendering index of 95.2 and a high luminous efficiency of 120.9 lm/W under power density of 2.39 W/mm2 irradiation. The above superior characteristics imply that the multi-color PIG is an ideal candidate for high-quality white laser lighting applications.