根据小型Offner凸光栅光谱成像仪光学系统的特点,对其反射镜支撑结构和桁架结构进行了研究,完成了小型Offner光谱成像系统的结构设计,建立了系统的3D实体模型。为了验证结构设计的合理性,对设计的3D模型进行有限元分析。在模态分析中得到该结构的第一阶固有频率为362 Hz,高于系统设计要求的120 Hz;在加速度及温度载荷分析中,得到主要光学元件的面形值以及它们之间的相对位置变化,其离轴及偏角均在允许公差范围内,说明结构刚度满足使用要求,证明了结构设计的合理性。

On the basis of characteristics of optical systems of Offner spectral imagers,the material choices of every parts,structure design of mirrors and frames in the imagers were investigated,then the structure design of a compact Offner spectral imaging system was achieved and its 3D model was established.In order to prove the reasonability of the structure,the 3D model was analysed by finite element method.The analysis results indicate that the first natural frequency of the structure is 362 Hz,which is higher than 120 Hz requested by the system.Furthermore,the analysis results of weight and temperature indicate that the RMS of surface figure,distances,centrifugal axes and the deflection of angle in every important parts all meet the requirements of the system tolerance.These results validate the rationality of structure of the compact Offner spectral imaging system.