大口径长焦距相机主次镜支撑结构方案初步研究

Research on Support Structure between Primary and Secondary Mirror in Large-aperture and Long-focal-length Space Camera

随着航天技术的迅猛发展,为了实现高分辨率的对地观测,大口径、长焦距的空间相机已成为发展趋势。连接相机主镜和次镜的支撑结构,很大程度上影响相机的成像性能和稳定性,是光学系统的敏感环节。为了得到更好的成像品质,文章选择了筒式、三杆式与桁架式这3种支撑方案作为研究对象,通过工程分析软件对每种结构的设计参数进行优化并进行有限元分析,通过对结构的力学稳定性、热稳定性以及质量等因素的综合考虑,最终选择桁架式支撑结构为最优方案,更适合于大口径、长焦距相机的发展趋势,并提出了该种结构进一步优化的空间与方向。

With the rapid development of space technology, large-aperture and long-focal-length space camera has become a trend in order to achieve high-resolution earth observation. And the support structure of space camera that connects the primary mirror and secondary mirror, is a sensitive part of the optical system due to its large affect on the stability and image quality of the camera. In order to get better image quality, the three support schemes including cylinder, three-rod and truss, are studied in this paper with size optimization and finite element analysis on the engineering software. By considering the mechanical stability, thermal stabil-ity, weight and other factors, the truss support structure is the optimal solution that is more suited to the devel-opment of large aperture and long focal length of a space camera. Meanwhile, the paper proposes the scope and direction for further optimizing truss structure.