腔长微调节结构在光学谐振器里有重要应用。一种由双楔镜组成的腔长微调节结构被提出，该结构可实现不依赖于腔镜的腔长调节。双楔镜结构由斜面平行对立放置的两个直角楔镜构成，通过在垂直方向上驱动楔镜移动实现双楔镜内部光程改变，进而改变所处谐振腔内光路的光程。双楔镜结构对光程改变量的理论计算公式被建立，根据公式，光程改变量与楔镜楔角大小成正相关关系，与楔镜折射率成正相关关系，与楔镜振幅成线性关系。楔镜的楔角和折射率共同决定双楔镜结构的光程调节效率。经理论设计，楔角29°、折射率1.81的YAG双楔镜结构具有较高的调节效率和较小的光损耗，调节系数为0.53。实验上，以双角锥环形腔为基础，实现了双楔镜结构对腔长的调节，验证确定了双楔镜结构对腔长调节的可行性和有效性。讨论分析了双楔镜结构的变形结构：直角面对立双楔镜结构、基于正楔镜的双楔镜结构、多级双楔镜结构的光程调节性能。对比了双楔镜结构和其变形结构在光程调节效率、光损耗、光路调节难易程度的性能，确定了各种双楔镜结构在实际应用中的优缺点，为双楔镜结构的设计和选择提供了参考依据。

We demonstrate a single-longitudinal-mode Ho3+:YVO4 unidirectional ring laser based on the acousto-optic effect, utilizing the features of the acousto-optical Q switch and half-wave plate to achieve unidirectional operation. The maximum power achieved in the single-longitudinal-mode at 2053.9 nm is 941 mW when the absorbed power is set as 4.4 W, yielding a nearly 50% slope efficiency. The M2 factor is 1.1. The results show that such a technique offers a potentially promising new method for achieving a high power and narrow linewidth 2 μm single-longitudinal-mode laser.

We demonstrate a diode-pump Tm3+-doped all-fiber laser operating at 1908 nm based on a master oscillator power amplifier (MOPA) configuration. In our work, 152 W of laser output power is generated by a total incident pump power of 434 W at 790 nm, corresponding to the total optical efficiency of 35%. The laser wavelength is 1908.29 nm. To the best of our knowledge, it is the highest output power reached around 1908 nm with such a narrow linewidth of 0.18 nm based on a MOPA configuration.