荧光转换白光激光二极管荧光玻璃主动散热研究

Active heat dissipation of phosphor-in-glass in phosphor-converted white laser diode

提出一种主动散热的荧光玻璃(PiG)用于反射型白光激光二极管(LD)封装,利用热电制冷器(TEC)的帕尔帖效应来增强荧光玻璃热耗散,降低大功率激光激发下荧光玻璃工作温度,从而提高白光激光二极管光热性能.将荧光玻璃浆料涂覆在热电制冷器冷端陶瓷基板表面,再通过低温烧结获得荧光玻璃膜-热电制冷器(PiG-TEC)结构.当激光功率从1.1 W增加到6.2 W时,荧光玻璃的工作温度从-5.9℃缓慢增加到23.8℃,最高工作温度仍处于较低水平.当激光功率为6.2 W时,采用热电制冷器主动散热的荧光玻璃的工作温度降低了49℃(约67%).此外,在不同激光功率下,荧光玻璃膜-热电制冷器封装的白光激光二极管均表现出稳定的光学性能.当激光功率为6.2 W时,白光激光二极管的光通量为756.1 lm,色温为5 132 K,CIE色坐标为(0.343 5,0.379 5).实验结果表明:利用热电制冷器的帕尔帖效应实现了荧光玻璃的主动散热,满足了大功率荧光转换白光激光二极管封装需求.

In this work,a reflective phosphor-converted white laser diode(pc-wLD) encapsulant with a thermally self-managing phosphor-in-glass(PiG) converter was proposed.Through utilizing the Peltier effect of thermoelectric cooler(TEC) to increase the heat dissipation of PiG,the working temperature of PiG under high-power laser excitation was decreased and the photothermal performance of pc-wLDs was enhanced.The PiG-TEC structure was prepared by printing and sintering a phosphor glass film on the cold side of thermoelectric cooler. As the laser power increases from 1.1 W to 6.2 W,the working temperature of the PiG film increases slowly from -5.9 ℃ to 23.8 ℃,the maximum temperature remains relatively low. The working temperature of PiG equipped with a thermally self-managing TEC is reduced by 49.0 ℃(about 67%) at the laser power of 6.2 W. Moreover,the pcwLDs with PiG-TEC structure achieve stable light quality under various laser powers. At the laser power of 6.2 W,the luminous flux,the correlated color temperature(CCT),and the chromaticity coordinate of the pc-wLD is 756.1 lm,5 132 K and CIE chromaticity coordinates(0.343 5,0.379 5),respectively.The results demonstrate that the Peltier effect of TEC achieves active heat dissipation of PiG and satisfies the encapsulant demands of high power phosphor-converted white laser diodes.