电激励红外多波段化学激光器的光腔参量选择

腔镜曲率半径和腔长的选配对于激光器的输出特性有重要的影响。以HF为例，在某电激励红外多波段化学激光器平台上，选取了耦合输出率为15％的四组不同曲率半径腔镜的组合，在其他工作参量相同的前提下，获得了一组与模体积最大化原则预测结果恰好相反的功率输出数据。结合烧蚀的光斑模式，利用Rigrod发展的一种基于ABCD传输矩阵的等效简化处理方法对实验结果进行了分析，推测原因可能在于增益区气流通道长矩形截面在高度方向上所形成的衍射损耗。结论表明对于此类器件，在光腔参量的选择中应该考虑到这种衍射损耗。

Choice of Cavity's Parameters for a Discharge Driven Infrared Multi-Band Chemical Laser

The influence of cavity mirror′s curvature and cavity length on laser performance cannot be under-estimated. A group of power output experimental data was obtained under same running conditions for four combinations of cavity mirror with output coupling of 15% near 2.7 μm but different curvatures on a discharge driven infrared multi-band chemical laser, and it is contrary to the principle of mode volume maximization. With the help of burned laser mode patters, a rather simple method introduced by Rigrod based ABCD matrix theory was taken to analyze the complex experimental result and it seemed that the problem rests in the diffraction loss induced by gain region gas channel′s transverse rectangular slit cross-section at height direction. The conclusion is that for these devices, this kind of diffraction loss should be considered at the choice of cavity′s parameters.