强激光腔镜温升对腔几何参数和远场光强的影响

 利用交替方向隐式有限差分法分析了高能激光器虚共焦非稳腔反射镜的温度场及热变形的数值计算方法。以单晶硅为例，计算了反射镜由于吸收激光能量而形成的温度场分布以及由此引起的热变形对谐振腔几何结构参数的影响，并在此基础上数值模拟了热畸变情况下正支虚共焦非稳腔的远场光强分布。计算结果表明:在激光束辐照的开始阶段，温升场主要集中在激光束辐照的中心区域内，在整个镜面上远未拉平，由此引起的厚度方向温升分布也是如此，很不均匀。

Influences of temperature rise of high-power laser cavity-mirrors on resonator parameters and far-field intensity

The influences of the thermal deformation of resonator mirrors induced by absorption of laser energy on geometric structure parameters of unstable resonators and intensity distributions of the far field were theoretically analyzed using finite difference methods.The farfield intensity distribution of virtual confocal unstable resonator under different thermal distortions was simulated.The results show that the resonator parameters changed significantly due to thermal deformation of the mirrors,and the central intensities of the far fields reduced obviously with thermal deformation increase.