基于自再现原理，利用菲涅耳基尔霍夫衍射积分方程，引入腔镜失调、激光介质上的增益分布以及光阑口径，采用本征矢量法分析了大口径平凹腔薄片激光器的本征模式，并计算了相应的光束质量因子M2。建立了千瓦级薄片激光系统和光纤扫描光斑诊断装置，开展了高功率激光输出特性研究。结果表明，在大口径高功率平凹腔中多个本征模式可同时起振，获得高功率激光输出，有较大的失调容限；输出功率随腔镜失调角度的增大而减小；失调容限随孔径光阑尺寸的减小而减小；失调引入了新的模式竞争，光束质量因子M2随腔镜失调角度的增大而变小。所得结果为高功率、高光束质量激光系统设计提供了有用参考。

Based on self-recurrence method and Fresnel-Kirchhoff diffraction formula, we have studied eigen modes and their beam quality factor M2 in the large-aperture high-power thin disk laser with gain distribution, aperture stop and tilt mirror, etc. By using eigenvector method. The large-aperture thin disk kilowatt laser system and fiber-scan measurement device is developed. The output characteristics of large-aperture thin disk laser have been studied both experimentally and theoretically. The results show that large-aperture high-power plano-concave resonator contains many eigen modes, has high misalignment tolerance, can obtain high-power laser output; the output power is quadratic function of the mirror tilt angle; the misalignment tolerance decreases as the aperture stop diameter decreases. The misalignment may bring forth new mode competition. M2 decreases as the tilt angle increases. The results obtained will be useful for the design of the high-power laser system.