ABSTRACT Laser‐excited phosphor is a promising technology for new‐generation laser lighting. However, traditional plain‐like inorganic color converters exhibit limited thermal‐optical performance. Herein, novel phosphor‐in‐glass film (PiGF) converters based on 3D‐patterned Al 2 O 3 ceramic substrate, including hill‐like (PiGF‐H) and valley‐like (PiGF‐V) configurations, were constructed. Conformal PiGF preparation was achieved by regulating the fluidity of La 3 Si 6 N 11 :Ce 3+ phosphor‐glass paste during printing and sintering on substrates. The thermal‐optical performance was comprehensively evaluated and compared with conventional plain‐like PiGF (PiGF‐P). The inclined side walls of the 3D‐patterned surface promote multiple reflections and enhance the light excitation of the blue laser, enabling the PiGF‐H to substantially outperform the PiGF‐V and the PiGF‐P under 6–42 W blue laser excitation. The PiGF‐H achieves a high luminous flux of 4123 lm@36 W, significantly exceeding the PiGF‐V (2166@21 W) and the PiGF‐P (1701@18 W). Moreover, the PiGF‐H has the highest luminous efficacy with minimal attenuation, an optimal normalized spectral intensity distribution, and an appropriate white light with a correlated color temperature (CCT) of 4874 K. The operating temperature of PiGF‐H (240°C) is considerably lower than that of PiGF‐V (335°C) and PiGF‐P (359°C). This work provides valuable guidance for enhancing thermal‐optical characteristics of color converters in advanced laser lighting applications.
Zhao et al. (Mon,) studied this question.