高功率980nm垂直腔面发射激光器的亮度特性

在循环水冷却(工作环境温度控制在15℃)和连续注入电流条件下,从垂直腔面发射激光器(VCSEL)亮度基本定义出发,实验测量了不同注入电流时口径为400μm的高功率980nm InGaAs/GaAs应变量子阱垂直腔面发射激光器(VCSEL)的亮度特性。结果表明:在注入电流4 A时,随着注入电流的增加,亮度也跟着增加;当注入电流4A时,尽管输出功率在增加,但是器件的光束质量变差,M2因子升高,表明此时影响器件亮度的主导因素是M2因子,所以亮度减小;在注入电流为4A,输出功率为1.2W时,亮度达到最大值2.43kW/cm2.sr,此时的光束质量最好,M2因子为207。最后,分析了影响高功率VCSEL器件亮度特性的主要因素,提出了提高器件亮度特性的解决方法。

Brightness characteristics of 980 nm high power VCSEL

On the basis of the brightness definition of Vertical-cavity Surface-emitting Lasers(VCSELs), the brightness characteristics of high power strained quantum well 980 nm InGaAs/GaAs VCSEL with a diameter of 400 μm are demonstrated at continuous-wave(CW) operation with a recycled water cooling(the temperature is controlled at 15 ℃). The results show that when the injection current is smaller than 4 A, the brightness will increase with the increasing of injection current; while the injection current is larger than 4 A, the output power increases with the increasing of injection current, but the beam quality becomes bad, and then the M² is the main factor impacting on the brightness characteristics. When the injection current is 4 A and the output power is 1.2 W, the beam quality is the best, M² factor achieves 207, and the maximum brightness is 2.43 kW/cm²·sr. Finally, the main factors that impact the brightness characteristics of high-power VCSEL devices are analyzed, and the solutions to improve the brightness characteristics of the device are also proposed.