激光器与单模光纤球透镜耦合的蒙特卡洛分析

为了研究半导体激光器与单模光纤在采用球透镜耦合方式的封装过程中不同耦合参量对耦合效率的影响,建立了半导体激光器与单模光纤通过球透镜耦合的光传输模型。基于ABCD矩阵和高斯光束与单模光纤耦合理论,计算了半导体激光器与单模光纤的球透镜耦合效率,以光功率下降0.5dB为评判标准,给出了在透镜半径为0.5mm时的各参量容忍度。采用蒙特卡洛分析方法,结合耦合效率计算模型,模拟仿真了各参量满足正态分布时的耦合效率分布状况。结果表明,能达到的最大耦合效率为0.616,最大概率耦合效率为0.585,参量区间缩小一半对耦合效率的提升较明显,但进一步缩小参量区间对耦合效率的提升不明显。此研究方法对激光器件封装过程中的对准单元精度选取与耦合效率预估具有指导意义。

Analysis coupling between a laser and a single-mode fiber with a ball lens based on Monte Carlo method

In order to study effect of different parameters on coupling efficiency between a semiconductor laser and a single-mode fiber with a ball lens, its optical transmission model was established. Based on ABCD matrix and the coupling theory of Gaussian beam to a single-mode fiber, its coupling efficiency was calculated. The parameter tolerances were obtained when the coupling efficiency decreased 0.5dB and the ball lens was in 0.5mm radius. Combined with coupling efficiency calculation model, the coupling efficiency distribution was simulated with Monte Carlo method when the parameters met the normal distribution. The result shows that maximum efficiency reaches 0.616 and the maximum likely efficiency is 0.585. The efficiency improves significantly as the parameters’ tolerances reduce by half. But further narrowing of tolerances can’t enhance the efficiency obviously. The research approach is instructive for selection of alignment units and estimation of coupling efficiency in laser device package.