# Three-Band Spectral Camera Structure Design Based on the Topology Optimization Method
## 1 Introduction
[PERSON] [19] designed a size optimization strategy with the fundamental frequency as the objective function, obtaining the optimal distribution of materials in the support structure of a space multispectral camera, resulting in a configuration with high stiffness and favorable dynamic properties. On the other hand, topology optimization reduces the material usage while maintaining both the quality and the robustness of the structures [20]. Although topology optimization alters the structure, it effectively enhances the performance by optimizing the material distribution and improving the structural efficiency. [PERSON] et al. [21] optimized the flexible vibration-damping support structure of a space camera through topology optimization, targeting the RMS values of random responses. [PERSON] et al. [22] optimized the main load-bearing substrate of a camera through topology optimization, reducing its weight from 36.8 kg to 15.6 kg, achieving a weight reduction rate of 58.2%. Similarly, [PERSON] et al. [23] used topology optimization to refine the main support structure of the optical system in a space camera. After optimization, the first-order natural frequency of the primary support structure increased from 41 Hz to 72 Hz, while its weight decreased by 15%. Lastly, [PERSON] [24] applied topology optimization for the lightweight design of a 300-mm-aperture secondary mirror structure, ensuring that the RMS of each reflective mirror surface met the requirement of being less than 12.6 nm. In summary, contemporary research primarily focuses on optimizing individual structural components, while studies on the overall load-bearing framework remain relatively scarce. In particular, the structural design of three-band cameras is relatively underexplored, with structural optimization in this domain being even more limited. This underscores the critical need for focused research and development regarding their supporting structures. Moreover, existing optimization methodologies tend to emphasize either topology optimization or parameter optimization, with limited investigation into their interactions. This gap constrains advancements in multispectral camera design, as the integration of these optimization approaches is crucial in achieving more efficient and robust structures. Three-band cameras' structural optimization remains a key focal point, requiring further exploration to bridge existing gaps and drive innovation in the field. The purpose of this study is to perform the topology optimization of the overall support structure of a camera to achieve an optimal solution. Using a simulation analysis platform, topology optimization is applied to the housing and support components. For structural components that meet performance requirements but exhibit redundancies, further refinement is conducted through parameter optimization to enhance the design stability and precision. The final design is validated through static and dynamic analyses, as well as imaging tests, confirming its performance and reliability. This study provides a reference for the development of three-band camera structures.