一种非稳腔计算机辅助装调方法的数值模拟

Numerical Simulation for Computer-Aided Precise Alignment of Unstable Resonator

谐振腔的自动准直技术是高功率激光器工程实践中的关键技术之一。针对这一问题，对非稳腔的计算机辅助装调方法进行了研究，并对该过程进行了数值模拟。在失调参量和像差系数小范围内线性近似的前提下，获取到一系列表征系统失调的像差值之后，通过求解线性方程组来计算系统的失调量。根据求解结果对失调系统进行修正。数值模拟结果表明单结构参量失调可以很快求出，多结构参量失调情况通过几次迭代求解后也能得到比较理想的结果。目前已经可以确定多个同时存在的失调量（包含倾斜和偏心）。倾斜量的求解范围约为10～10^4μrad，偏心量的求解范围约为10^-2～1mm。这种辅助装调方法能够有效地指导谐振腔的精装调过程，为今后实际的激光器谐振腔系统的自动调节提供了一种方法。

The automatic alignment of resonator is one of the critical techniques in high-power laser technology. The method of computer-aided alignment of unstable resonator is presented and its numerical simulation results are given. The relation between mirror misalignments and its phase aberration coefficients is regarded as linear to some extent, especially under the condition of small misalignments. Mter getting a series of aberrations representing a misaligned system, we get the data of each misalignment by solving linear equations. Then the misaligned resonator is modified according to these results. The whole process is simulated numerically. Presently, multi-misalignments including both tilt and decentration can be calculated in this way. The numerical analysis shows that it is easy to figure out a single misalignment. Complex misaligned condition needs iteration. Tilt misalignments that can be figured out is 10～10^4μrad and the decentration range is 10^-2～1mm. This method can be used to guide resonator＇s alignment effectively and provide another way for laser resonator＇s automatic alignment in Dractical use.