在常规重复频率77MHz掺钛蓝宝石飞秒激光器的基础上,通过腔内引入Herriott型多通望远镜系统增加总腔长及对腔内色散的深入分析和实验控制,实现了低重复频率、高脉冲能量飞秒激光振荡的稳定运行.在连续功率8.2W的532nm激光抽运下,得到了重复频率11MHz、单脉冲能量达72.73nJ、对应峰值功率MW量级的结果.相对80MHz重复频率下6.25nJ的单脉冲能量及150kW的峰值功率,其输出能力提高了约一个量级. On the basis of 77MHz Ti: sapphire femtosecond laser with repetition rate of 77MHz, the introduction of Herriott multifocal telescope system to increase the total cavity length and the in-depth analysis and experimental control of intracavity dispersion have realized the low repetition rate and high pulse energy Femtosecond laser oscillation stable operation.Under the 532nm laser pumping with continuous power of 8.2W, we get the result that the repetition frequency is 11MHz and the single pulse energy is 72.73nJ, corresponding to the order of the peak power MW.Compared with the 6.25nJ Single pulse energy and peak power of 150kW, the output capacity increased by about one order of magnitude.