Thermal dynamic modeling of laser diode cooling system considering surrounding ambient condition

Laser-driven white lighting consists of blue laser diode (LD) and yellow phosphor, and it is attracting attention as a future lighting technology due to its advantages such as high luminous intensity, efficacy and the possibility of miniaturization. The optical efficiency of LD is highly affected by the temperature, cooling system is critical for many practical applications such as automotive headlamp. This study presents a single phase liquid cooling system which was selected for both higher cooling performance and lower consumption power. Also, a thermal dynamic model was proposed for predicting the LD temperature with experiment to validate the model. The system consists of an LD, heat spreader, heat sink and liquid pump. A heat spreader was designed with liquid cooling channels based on the model in consideration of both the thermal resistance and pressure drop. Also, the effect of surrounding ambient conditions was analyzed for considering real vehicle situation.