大视场高分辨率可缩放计算光学成像研究

Imaging system with large field-of-view and high-resolution plays a key role in the fields of space remote sensing, earth observation, and defense security. Based on the design idea that optical system with multi-aperture has the ability of precision aberration correction and that with single aperture may obtain high-resolution after aberration correction, a new type of computational optical imaging system with large field-of-view and high-resolution is studied, and the space-bandwidth product scales with its dimension. Through the research on the imaging theory, the optimally design and realization methods, the imaging model and aberration theory is found. And a new image registrtion method based on the Coutourlet unified frame is also studied. It will realize a smooth high-precision registration, and obtain a high-resolution and large field-of-view panoramic image without Mosaic. Then the computational simulation and the imaging experiment are performed to verify the researched theory, the design methods and the stitching algorithm, respectively. This project breaks through the current restrictions from optical imaging idea and the image stitching method, and an innovative type of imaging is realized. It has great significance for developing optical imaging system with small size, large field-of-view, and high-resolution.

大视场高分辨率成像系统在空间遥感、对地观测和国防安全等领域具有重要用途。本课题拟采用多孔径系统可精细校正像差和校正像差后的单孔径系统可获得高角分辨率的思想，研究空间带宽积性能可随系统尺寸缩放的大视场高分辨率新型计算光学成像系统。研究其成像理论、优化设计方法及实现方法，建立一种可缩放计算光学成像系统的成像模型和像差理论。研究基于Contourlet统一变换框架的图像拼接新方法，实现子图像间的平滑过渡和高精度无缝拼接，获得消除Mosaic现象的高分辨率大视场全景图像。通过仿真研究验证理论和设计方法的正确性，并通过成像实验验证图像拼接算法的有效性。本课题将从光学成像思想和高精度图像拼接方法两方面突破现有方法的约束，实现一种新型大视场高分辨率成像方法，对于小型化、大视场、高分辨的光学成像系统的发展具有积极的参考作用。

在空间遥感、对地观测、国防安全等的许多应用领域中，对于成像系统空间带宽积（Spatial Band-width Product, SBP）性能的要求不断提高，要求其在很宽的视场内、有极高的角分辨率。而采用结构简单紧凑、成本低廉的光学系统，要在大视场内实现接近于衍射极限的分辨率，对于当前的设计来说是一个极具挑战性的问题。本课题采用多孔径系统可精细校正像差和校正像差后的单孔径系统可获得高角分辨率的思想，可利用简单的结构和设计，使全视场获得衍射极限的成像性能，克服了传统方法大口径、大视场系统像差校正困难、系统复杂、成本高等缺点。进一步，基此优化设计了视场100º、分辨率千兆像素的大视场高分辨光学成像系统，像质评价结果表明其具有可缩放特性；通过研制具有七个子通道的多尺度成像系统原理样机，利用该原理样机进行光学成像，获得了较好的光学图像，验证了其轴外视场与中心视场成像性能的一致性。为下一步开展宽视场高分辨成像系统奠定了坚实的基础。为开展凝视型大视场高光谱成像系统提供了新方法。