The excellent luminous efficiency and high thermal stability of phosphor-in-glass for high-power laser

At present, fluorescent glass mainly emits a single yellow light. The characteristic of green and red luminescent materials limits its omni-directional combination with yellow light materials, resulting in high correlated color temperature and low color rendering index of laser lighting devices, which seriously reduces the quality of laser lighting. Therefore, the development of multi-color fluorescent glass to improve the color quality is a huge challenge in laser lighting technology. In this research, the glass matrix that can be compounded with multi-color phosphors is proposed to solve the problems of phosphor decomposition, oxidation, corrosion, and blackening during the vitrification process. Surprisingly, a 50 wt. % Ce:YAG&1.5 wt. % CaAlSiN3-PiG (50 Y&1.5 R-PiG) sample exhibits an excellent internal quantum efficiency of 94% and achieves a high luminous efficiency of 184 lm/W under laser irradiation. Moreover, an ultrahigh luminous efficiency of 331 lm/W is realized by using a laser device with a heat sink. It demonstrated that Y&R-PiG can own excellent application prospects in high-quality lighting fields, such as laser displays and automobile headlights.