摘要
激光器的谐振腔在实际装配过程及运行过程中很难保证完全调准,因此研究谐振腔的稳定性十分必要。采用"Rigord分析法"分析了抛物面镜离轴非稳腔和球面镜腔角度失调时功率提取效率的变化,对腔长改变时两种谐振腔的输出特性进行了讨论,同时研究了腔镜曲率半径增大的抛物面镜离轴非稳腔的稳定性。结果表明,当失调角度在±6 mrad变化时,抛物面镜腔的功率提取效率比球面镜腔高5.6%;当谐振腔腔长的变化值在―1~1 mm的范围内时,抛物面镜离轴非稳腔的功率提取效率比球面镜腔高3.5%;当谐振腔腔镜曲率半径增加2 mm时,抛物面镜腔的功率提取效率增加,且抗失调特性更好。
It is difficult to ensure perfect alignment of the laser resonator in the process of actural assembly and operation process. Therefore, it is necessary to study the stability of resonator. The "Rigord analysis method" is used to analyze the variation of power extraction efficiency for parabolic mirror off-axis unstable resonator and spherical mirror resonator, when the angle is out of adjustment. The output characteristics of the two types of resonator are discussed, and the stability of the off-axis unstable resonator is studied when the radius of curvature of the resonator mirror increased. The results show that the power extraction efficiency of the parabolic mirror resonator is 5.6% higher than that of the spherical mirror one when mirror tilt angles varied between ―6 mrad to 6 mrad. For parabolic mirror resonator, the power extraction efficiency is 3.5% higher that of the spherical mirror resonator, when the variation of cavity length is in the range of ―1 mm to 1 mm. When the radius of curvature of resonator mirror is increased by 2 mm, the power extraction efficiency of the parabolic mirror resonator is increased and the anti-misalignment characteristics are better.
引文
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