共衍射阵列成像多视线波前传感技术研究

Multi-line-of-sight wavefront sensing in a wide field of view has become a key technology for next generation multi-reference astronomical observation, multi-object laser propagation and some related areas Existing multi-line-of sight wavefront sensing achieves wavefront measurements by simply increasing the number of wavefront sensors or using some prior information. The algorithm for wavefront reconstruction still belongs to the traditional single-line-of-sight wavefront detection. This solution will increase the system complexity significantly. Therefore, this issue carries out a method research for multi-line-of-sight wavefront sensing based on a common diffraction element array and presents the idea of multi-wavefront separation and parallel reconstruction based the superposition image of the spot arrays of multi beams. A theoretical model for multi-line-of-sight wavefront reconstruction with a single Hartmann-Shack wavefront sensor will be built. The method adopts a detection mechanism that multi beams from multi objects imaged with a common diffraction element array and researches the space/frequency domain characteristics of the overlay image of the multi spot arrays. The mapping rule between the aberration modes and spot-array grid distributions will be explored. The algorithm verification and experimental investigation would also be developed. This project is committed to promoting a breakthrough for Hartmann-Shack wavefront sensing in the nature of the measure dimension from a ‘point’ source to a ‘surface’ view. Compared with traditional single-line-of-sight wavefront reconstruction algorithm, this method could provide a more advanced technique for wavefront detection and correction in conditions such as wide field of view and multi objects.

宽视场多视线波前探测已经成为下一代多信标天文观测、多目标激光传输等领域重点攻关的关键技术。现有的多视线波前探测主要通过简单地堆砌硬件数量（采用多个传感器）或者依赖先验信息来实现多波前重构，其波前重构机制仍属于传统的单视线波前探测范畴，致使系统复杂度线性增加。为此，本课题开展共衍射阵列成像多视线波前传感技术研究，基于多视线光束阵列叠加图像，提出多波前信息分离并行重建思想；基于单个哈特曼-夏克波前传感器结构，构建多视线波前重构的理论模型；引入多目标多视线光束共衍射成像的探测机制，掌握像差模式与光斑阵列网格分布映射规律，明晰多视线光斑阵列叠加图像空域/频域分布特征；并开展多视线波前并行重构的算法研究和实验验证。该技术致力于推动哈特曼-夏克波前传感技术测量维度从“点”源至“面”视场的本质突破，与传统的单视线波前重构方法相比，可为宽视场、多目标条件下的波前探测与校正提供一种更先进的技术手段。

宽视场多视线波前探测已经成为下一代多信标天文观测、多目标激光传输等领域重点攻关的关键技术。现有的多视线波前探测主要通过简单地堆砌硬件数量（采用多个传感器）或者依赖先验信息来实现多波前重构，其波前重构机制仍属于传统的单视线波前探测范畴，致使系统复杂度线性增加。为此，本项目提出开展共衍射阵列成像多视线波前传感技术研究。项目围绕多目标光束波前重构的研究目标，主要开展了共衍射阵列成像多视线哈特曼波前传感器数值模拟仿真平台、基于子孔径重心偏移变波门双光斑质心自动提取算法、基于部分子孔径的全局光斑质心推定方法、基于大气湍流像差传输模型的多视线波前关联特性研究分析、基于边缘检测和领域搜索的子孔径中多个子光斑质心提取方法、共衍射阵列成像多视线波前实时并行重构原理实验和实际场景验证等一系列研究工作，突破了完整的、面向实际应用的多视线哈特曼波前传感关键技术，可实现对多视线波前实时并行重建，提出了一种基于部分子孔径信息的哈特曼波前传感器全域子孔径信息推定技术，可将哈特曼波前传感器低质量、缺失的子孔径信息补全，掌握了基于大气湍流像差传输模型的多视线波前关联特性和多光束光斑阵列叠加特性，形成了多视线哈特曼波前传感器探测过程可等价于对多视线信标这类特殊扩展目标成像的模型认识，搭建原理实验获得了5视线、5′级宽视场的多视线波前并行重建数据，开展了国内首次激光大气传输双视线波前探测与校正技术验证试验，获得了宝贵的多视线波前探测校正的实测图像数据和波前重建数据，观测到了不同条件的非等晕像差数据。项目研究成果不仅在理论上探索了一条新的多视线波前探测技术路线，而且充分验证了多视线波前探测对实际大气湍流像差和非等晕像差测量的可行性，可推动单个哈特曼波前传感器的波前探测维度由单一视线的“点”向多个视线的“面”发展，为宽视场、多目标条件下的波前探测与校正提供了一种更先进的技术手段。