报道了一种基于周期性极化掺氧化镁铌酸锂晶体(MgO: PPLN)的高峰值功率、纳秒宽调谐中红外光参量振荡器(Optical parametric oscillation, OPO)。采用重复频率30~50 kHz、脉冲宽度小于4 ns的高光束质量1064 nm基频光泵浦基于极化周期为29 μm MgO: PPLN的OPO，当MgO: PPLN温度为80 ℃时获得30 kHz、脉宽1.19 ns、峰值功率48.45 kW的3.93 μm激光输出。在MgO: PPLN 温度区间为50~200 ℃时，中红外调谐输出波长为3.77~3.96 μm。根据实验结果分析讨论了不同重复频率下转换效率的特点、温度调谐特性与理论分析的一致性。

受激布里渊散射(Stimulated Brillouin Scattering, SBS)是一种光学三阶非线性效应，其反射光具有相位共轭特性，在振幅、相位、偏振方面与入射光呈现时间反演关系，并保持与入射光相同的波前。在主振荡功率放大（Master Oscillator Power-Amplifier, MOPA）结构的纳秒激光器中，激光放大器中的热效应及光路中大量的光学元件使传输光束存在严重的波前畸变，在恶化光束质量的同时也限制了功率进一步提升的可能性。在此类激光器中使用基于受激布里渊散射的相位共轭镜(Stimulated Brillouin Scattering Phase Conjugate Mirror, SBS-PCM)，使光束往返通过引入严重波前畸变的激光放大器能够实时补偿畸变，从而优化激光器的输出光束质量，并有利于功率的进一步提升，进而促进纳秒激光器向着兼顾高功率和高光束质量的方向发展，因此在高功率纳秒激光器中得到广泛应用。文中首先从理论方面简要介绍了SBS-PCM的基本原理及其相位共轭特性，其次对比了不同SBS-PCM介质的特点及适用范围，概述了国内外机构对SBS-PCM的研究进展及高功率纳秒激光器中SBS-PCM的典型应用情况及发展历程，并最终对SBS-PCM发展趋势进行了展望。

介绍了一种激光二极管叠阵（LDA）侧面Zigzag泵浦多边形薄片激光放大器构型，采用三维光线追迹方法进行了详细的模拟仿真，优化设计了此放大器系统的泵浦耦合结构，主要研究了多边形增益介质的掺杂离子浓度与侧面切角对介质内部泵浦光分布的影响。在晶体厚度1.5 mm、端面口径16 mm的条件下，侧面切角在35°～65°，Nd³⁺掺杂浓度为0.20 at.%～0.30 at.%时，模拟仿真中Nd：YAG多边形薄片对泵浦光的吸收分布较均匀，泵浦光分布均匀性均优于0.1，同时在实验中得到了平顶的荧光分布和增益分布。介质内储能的均匀平顶分布有利于实现高功率高光束质量的激光输出，为侧面Zigzag泵浦多边形薄片激光器系统的设计与进一步实验提供了重要参考。

A laser diode array side-pumped Nd:glass square rod amplifier of the dimensions 12 mm×12 mm is designed. The fluorescence is evenly distributed in the Nd:glass amplifier. When the pump power is 66.32 kW, the small signal gain increases by 3.23 times. Under the condition of a 1 Hz repetition frequency, 50 mJ of injected seed-light energy, and a 10 mm×10 mm aperture, the output energy of the laser beam can reach 1.62 J during the four-pass amplification. The output energy stability of the laser pulse is 2.94% (RMS), and the square pulse distortion is smaller than 2. The energy amplification of the injected laser beam from millijoules to joules is realized.

To obtain a laser output with a high-quality beam and a square, super-Gaussian, flat-top distribution, a high-energy laser needs to conduct spatial reshaping of the geometric outline of an injected Gaussian laser pulse and the non-uniform gain of multi-level energy amplification units. A digital micro-mirror device is very suitable for a working environment that has a high electromagnetic interference in a high-energy laser system. We present an algorithm and an experiment of spatial beam shaping that is based on the use of a digital micro-mirror device. Through secondary shaping, the near-field modulation degree of the beam (the ratio of the maximum value of the light intensity to the average value) decreases from 1.79∶1 (after primary shaping) to 1.24∶1, an improvement of 30.7%. The energy loss is 32.9%. Meanwhile, the beam after secondary shaping possesses extremely strong stability. Under the condition where the input-shaping aperture remains unchanged, the dispersity of the near-field modulation degree of the output beam is only 1.6%. Thus, the influences of the environmental changes and the random distribution of the “noise” in the beam intensity distribution are reduced.