基于最优Zernike模型系数最小化的共形光学像差校正机理研究

Aimed at the problems with traditional conformal optical aberration correction methods, including the narrow detecting field, the overcomplicating of the correctors and the loss of the adaptive correction strategy in consideration of conformal opticalaberration characteristic, and faced to the conformal optical system with a wide off-axis scanning field of view, we will be devoted to solve these above problems and to explore the conformal optical dynamic aberration correcting theory and method based on the dropping of Zernike mode coefficients. The main research contents include: 1) the Wassermann-Wolf theory is developed further , and the mutil-field-point aberrational-free original structure will be designed, thus the imaging field will be expanded to the limit with the assist of the adaptive wavefront correcting method; 2) the influence law of the deformable mirrors (DM) parameters to the conformal optical system residual aberrations after correcting should be revealed, and the optimal parameters should be given; 3)based on the above works, the adaptive wavefront closed loop correction mechanism which the mode coefficients of the optimal Zernike model decreasing are studied, and the acquisition method of the Zernike optimizing model which has the stronger aberration correcting ability and the fastest convergence speed is proposed. Thus on the basis of keeping the nice aerodynamic performance of the high-speed platform, the wide detecting field and real time imagery capability can be guaranteed，which will establish the foundation for the extensive use of conformal optics in the field of high speed aircraft.

针对以往的共形光学像差校正方法探测视场较小，校正器机构复杂，自适应波前校正策略未考虑共形光学像差特性等问题，面向超大离轴扫描视场的共形光学系统，深入探索基于Zernike模式系数下降的动态像差校正原理与方法。主要研究内容与目标为：1）进一步发展Wassermann-Wolf消像差理论，设计多视场点消像差初始共形结构，从而配合自适应波前校正手段，将成像视场增大到极限；2）揭示变形镜参数对共形光学系统校正后残差的影响规律，完成参数优化选取；3）在前两项的基础上探索基于最优Zernike模型中模式系数最小化的自适应波前闭环校正机理，建立像差校正效果好且收敛速度最快的Zernike最优化模型。从而在保证高速载体空气动力学性能的基础上，保证光电成像系统的大探测视场和实时成像性能，为共形光学技术在高速飞行器领域中的广泛应用奠定基础。

面向超大离轴扫描视场的共形光学系统，研究了基于Zernike模式系数下降的动态像差校正原理与方法。同时，针对目前搜索/跟踪红外成像系统探测器分辨率较低的问题，研究了基于压缩编码的超分辨成像机理与技术。分析了共形光学窗口随扫描视场像差变化规律，研究了 Wassermann-Wolf （W-W） 像差校正理论并基于此理论设计了大视场共形光学系统初始结构。构建了基于模型的遗传算法优化方法，推导了Zernike多项式系数与变形镜驱动器电压之间的转换矩阵，利用无波前探测器自适应光学系统校正残余像差。该方法比起驱动电压直接优化法，优化速度提高了20倍左右，共形光学系统波前校正算法收敛迭代次数<50 次，视场范围达±60°，且各个扫描视场的成像质量均接近衍射极限。通过仿真实验和桌面原理性验证实验，证明了该方法的可行性。本项目研究的共形光学系统在获得优良成像效果的同时计算速度优势明显；同时这种基于自适应变形镜的校正方法不会打破飞行器内部运动平衡，伺服控制实现难度较小。对可用于搜索/跟踪系统的红外超分辨成像机理与技术进行了研究，建立了基于“块状”压缩感知和光场编码的超分辨成像光学系统的基本成像模型，并进行了超分辨成像原理验证实验，验证了重建算法的有效性，获得了4倍超分辨倍率。设计了含DMD的超分辨成像光学系统，提出了装调误差对超分辨成像质量影响的分析方法。在成像模型中分别引入适当的偏心、倾斜、镜片间隔误差、离焦等装调误差，对超分辨重建结果进行仿真分析，得出了该超分辨成像光学系统装调时的公差范围。本项目的成功实施为自适应光学技术和超分辨率成像技术在共形光学红外搜索-跟踪系统中的工程应用提供了理论和实验基础。相关研究发表SCI收录论文6篇，EI收录论文11篇，授权专利5项，在国际会议上做特邀报告一次，培养3名硕士研究生，部分研究成果支撑吉林省科技进步一等奖1项。