高功率激光装置是一个复杂的有源巨型光学工程，其性能指标要求逼近科学技术与物理极限。驱动器研制有物理设计、工程光学和结构工程设计三大过程，工程光学在其中起着重要作用。高功率激光装置工程光学设计需遵循其特有的设计原则和要点，以保证装置的高性能。根据驱动器设计指标和设计特点，从总体光学设计、光束质量控制以及光束打靶精度控制方面，综述了高功率激光装置工程光学设计中的关键科学技术问题以及相应解决方法，为未来高功率激光驱动器的发展提供必要的工程设计参考。

利用新型准直远场探测包光栅元件的双向衍射, 实现了空间滤波器的小孔准直, 特别是对同一段光路中两个空间滤波器的小孔对准.该方案克服了传统滤波器对小孔尺寸的限制并满足远场准直包高稳定性的要求, 在光路远场准直的同时实现了小孔中心位置的监测与准直调整, 并在以色列项目中得以成功应用, 装置实验结果表明: 针对装置15倍衍射极限大小的小孔, 对准精度小于小孔直径3%, 满足装置器件小孔对准调试小于小孔直径4%的要求.

高能拍瓦激光的高精度脉宽测量对离轴抛物面镜焦斑功率密度的诊断以及光栅损伤阈值的分析都具有重要意义。分析了光束指向性和近场分布的周期性调制这两方面的误差影响。结果表明, 当反射镜稳定性在5 μrad时,光束指向性的误差最大为0.03%。当近场调制周期增加时, 误差降低; 而调制度增加时, 误差增大。另外, 采用镜像结构能降低近场缺陷导致的测量误差。当调制深度为1.5、调制周期大于10时, 综合误差小于20%, 最小可降至10%。镜像结构的误差均小于15%, 最小可降至0。在拍瓦级激光脉宽测量实验中, 证实了近场调制对于脉宽测量的影响及改善效果。

Aiming at the disadvantage that the traditional measurement technique is sensitive to the incident direction of incident light, a beam-split technique of high power laser multi-parameter measurement based on integrating sphere is proposed. Numerical analysis and simulation about attenuation rate, time waveform of emergent light, and time waveform recovery of incident light are carried out by Monte-Carlo method, which validate the feasibility that the integrating sphere can be used as beam-splitter in laser measurement system. The energy and time waveform of nanosecond laser is measured based on integrating sphere. The theoretical analysis matches well with the experiment result. Experiment and simulation results show that spectrum parameter, energy parameter and time parameter of incident light can be recovered by measuring the parameters of the emergent light, when the light-split technique is used in laser parameters measurement. The proposed technique can conquer the disadvantage that the incident direction of incident light has great influence on the parameters of the emergent light in traditional technique. The proposed technical proposal possesses small volume and is easy to integrate, which can be used in modular design of multiple beam high power laser parameters measurement system.

Laser beam far-field alignment as well as frequency-doubling and frequency-tripling crystal adjustment is very important for high-power laser facility. Separate systems for beam and crystal alignment are generally used while the proposed approach by off-axial grating sampling share common optics for these two functions, reducing both space and cost requirements. This detection system has been demonstrated on the National Laser Facility of Israel. The experimental results indicate that the average far-field alignment error is <5% of the spatial filter pinhole diameter, average autocollimation angle error of crystals is <10 μrad, and average frequency-tripling conversion efficiency is 69.3%, which meet the alignment system requirements on the beam direction and crystals.

针对传统测量技术对入射光入射方向敏感的缺点，提出了一种基于积分球的高功率激光多参数测量的分光技术。采用蒙特卡罗法对衰减率、出射光时间波形特性、入射光时间波形恢复这三个方面进行了数值分析和仿真，验证了积分球作为激光测量系统中的分光元件的可行性。利用积分球对纳秒激光的能量和时间波形进行测量，实验结果与理论分析相符。实验与仿真均表明在激光参数测量中采用该分光技术，通过测量出射光各项参数可以恢复入射光的光谱参数、能量参数、时间参数，克服传统技术中入射光的入射方向对于出射光的各项参数有较大影响的问题。该技术方案占用空间小、易于集成，可用于多路高功率激光参数测量系统的模块化设计。

结合神光II升级装置腔空间滤波器远场准直的特点，通过建立孔间耦合模型，提出了一种孔间前馈补偿和孔内反馈调节相结合的多孔串并行综合准直控制方法。该方法通过位置预估和局部极值搜索来实现所有基准中心的提取,并依据图像Jacobian 矩阵，计算各反射镜电机的反馈控制量。将前孔准直调节量作为后孔准直扰动，并利用孔间耦合模型计算出后孔准直所需的前馈扰动补偿控制量，综合反馈控制量和前馈补偿量实现多孔的串并行准直调节。实验结果表明，基准中心的识别准确率达到97%以上，准直时间由约1 min缩短至30 s左右，在很大程度上提高了准直效率。

A new method is proposed to deduce the temporal resolution of a single-shot autocorrelator. A resolution test pattern is installed in one arm of the autocorrelator to add streaks on the beam cross section. Therefore, the autocorrelation signal is modulated when the streaked beam arrives at an autocorrelation crystal. Given the relationship between streak width and temporal delay in an autocorrelator, the temporal resolution is determined by the noncollinear angle, the streak’s width of the resolution test pattern, and the autocorrelation signal. Comparison experiments show that the proposed and conventional calibration schemes yield temporal resolutions of 65.6 and 67.8 fs∕pixel, respectively, with a relative error of 3.3%. An advantage of this method is that fine temporal resolution (65.6 fs∕pixel) is achievable on a short pulse (10 ps) despite the lack of a femtosecond pulse.

Pulse contrast is an important parameter for ultrafast pulses. It shall be 108 or higher in order to avoid effect from noise before main pulse. Diagnostics with cross-correlation can achieve high temporal resolution such as ~7fs. Cross-correlation has advantage in pulse contrast measurement than autocorrelation because it can distinguish noise before or after main pulse. High dynamic range is also essential in pulse contrast measurement. Cross-correlation signal from a single shot is converted into a signal series through fiber array, which can be analyzed by a set of a PMT and an oscilloscope. Noise from nonlinear crystal and scatter needs decrease to improve dynamic range. And pulse power is also discussed in pulse contrast experiments. Time delay τ is generated by travel stage in measurement for repetition pulses. Then energy instability will generate error in this measurement. In measurement for single shot pulse, time delay τ is generated by slant angle of beams. The scanning procession is completed with thousands parts of beam section within a single shot, and error will generated from no uniformity in near field. Performance test of pulse contrast measurement is introduced in subsequent sections. Temporal resolution is testified by self-calibration. Dynamic range is judged by a parallel flat. At last pulse contrast of petawatt laser is diagnosed by a single shot cross-correlator with high confidence. The ratio is 10-6 at 50ps before main pulse, and 10-4 at 10ps before main pulse.