Luminescence material characterizations on laser-phosphor lighting techniques

This study examines three different types of laser carriers, including the phosphors in silicone (PiS), the phosphor in glass (PiG), and alumina-based ceramic binders (CP), for laser-phosphor lighting characterizations via a laser projector light source module. The thermal influence of heat spreading on these phosphor materials and their luminescence performance is also investigated. The conversion efficiency of PiS, PiG and CP was found to be 29.7%, 34.6% and 31.8%, with their corresponding maximum laser power operations of 3.9 W, 7.9 W, and 17.2 W, respectively. This work further correlates the maximum laser operation power with the thermal conductivity of luminescence material. From the optical engine perspective, it was found that CP exhibits the superior thermal conductivity of 17.0 W/m⋅K for slight hot-spot IR observation and higher laser power operation. This work finally delivers a CP device for 50.2W maximum laser operation with the operating temperature below 100 °C. The simulation is also carried out in order to examine spreading resistance's influence, when subject to convective boundary condition. CP's response sensitivity to heat transfer coefficient was found to be rather small.