高功率980nm垂直腔面发射激光器的亮度特性

Brightness characteristics of 980 nm high power VCSEL

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。

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/cm^2· 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.