腔内像散扰动对正支共焦腔模式影响的数值分析

 针对激光器出光过程中腔内像差扰动带来的输出光束质量和光束能量下降问题，分析了腔内像差扰动对非稳腔模式的影响，并采用数值迭代法计算了理想情形和腔内像散扰动对无源正支共焦腔输出模式强度和相位分布的影响，进一步采用Zernike模式法对光束相位进行了像差拟合，得到了前35阶Zernike像差系数、点扩散函数(PSF)分布和环围能量曲线，计算了腔内像散扰动量与远场Strehl比的关系。结果表明：对小菲涅耳数正支共焦腔，腔内像散扰动对输出光束强度和相位分布均有明显影响，相位分布中一些高阶Zernike像差也有所增大。因此在进行腔内像差校正时，应优先考虑此类像差的校正。

Numerical analysis of mode properties for confocal unstable resonators with intracavity astigmatism-aberrated perturbation

For a laser resonator cavitiy using an unstable resonator configuration, experiments have proved that the intracavity perturbation is an important influencing factor for degrading the output energy and the beam quality. The influence on eigenmode properties for passive unstable resonators has been analyzed. The effect of the intracavity astigmatism-tilted perturbation on the mode properties for positive-branch confocal unstable resonators has been calculated numerically by using an iterative method. The phase structure of the output beam is analyzed by adopting the Zernike mode-reconstruction theory; and Zernike aberration coefficients of the first 35 order, integrated relative far-field intensity, and point spread function(PSF) are all obtained. These numerical results illustrate that sma