Unique Multilayer Gradient Design of Al2O3 Doping Phosphor-In-Glass Film Enabling High-Luminance Laser Lighting

Abstract

Next-generation high-luminance laser lighting faces a crucial challenge in developing a transmissive color converter with efficient heat dissipation and phosphor conversion. Herein, a unique architecture of Al₂O₃ particles gradient doping phosphor-in-glass film (PiGF) coated on a transparent sapphire (AGD-PiGF@S) is designed and prepared by a simple multilayer printing and low-temperature sintering strategy. By optimizing the multilayer gradient doping structure, the 9-0%AGD-PiGF@S converter enables a high-luminance white light with a high luminous flux (LF) of 2996 lm under a maximum laser power density saturation threshold (LPD-ST) of 19 W mm⁻², which is 2.63 times of the traditional PiGF@S converter with a LF of 1139 lm@11 W mm⁻². The working temperature of this AGD-PiGF@S converter is decreased by 35.8°C@11 W mm⁻² (≈23.82%). Compared with the Al₂O₃ uniform doping PiGF@S (4.5%AUD-PiGF@S) converter, the maximum LF and luminous efficiency (LE) of AGD-PiGF@S are increased by 58.18% and 33.20%, respectively. The findings will provide a new idea for realizing the preferably color converter in high-luminance laser lighting and display.