The study of planetary atmospheres and geology represents a fundamental area of research in deep space exploration and space astronomy. The advancement of wide-area detection and spectral identification of planetary climate changes, water-ice distribution, and surface topography provides essential scientific insights for understanding planetary origins and resource exploration. Contemporary deep space planetary exploration trends emphasize wide field of view (wide-FoV) coverage, high-resolution capabilities, multidimensional information acquisition, and comprehensive detection. Wide-FoV high-resolution camera payloads are crucial for mapping permanently shadowed or illuminated polar regions, analyzing small-scale terrain features, and achieving high-precision planetary surface mapping. Multi-wavelength global multispectral detection plays a vital role in prospecting planetary resources and identifying spectral signatures of minerals such as ilmenite and polar water ice. This study presents the design of a wide-FoV co-prism multispectral camera system for in-orbit deep space planetary exploration. The system utilizes a shared prism as a key optical element to achieve compact co-detection focal plane optics for wide-FoV multispectral imaging. The design accomplishes miniaturized detection with wide-FoV coverage and high spectral-spatial resolution, exhibiting superior imaging quality and favorable manufacturability and alignment characteristics. This system aims to contribute valuable insights to aberration theory research and system design studies of miniaturized wide-FoV multispectral cameras for deep space exploration.

This study implements a dual-band shared prism constructed from fused silica as the primary optical component, addressing the energy loss limitations of conventional dichroic beam splitters. This design enhancement substantially improves optical throughput efficiency and signal-to-noise ratio while optimizing the optical path configuration for system miniaturization. Utilizing ray geometric vector transmission theory, we develop a vector aberration model incorporating complex geometries for the wide-FoV co-prism multispectral camera. This model examines the correlations between key optical parameters—air spacing, equivalent optical path thickness of the prism, and prism angles—and fundamental aberrations including spherical aberration, coma, and astigmatism. Through integration of these analyses with system optical specifications, optimized initial structural parameters are designed for aberration reduction. The implementation of aspheric and cylindrical surfaces facilitated aberration and astigmatism correction optimization. System manufacturability and alignability are verified through tolerance analysis. Furthermore, the design encompasses a multispectral beam-splitting assembly and mechanical structure layout, enabling dual-band multispectral imaging detection for the integrated system.

The designed wide-FoV co-prism multispectral camera achieves multispectral imaging detection across a broad spectral range from 0.29 μm to 0.80 μm. It features a 60° wide-FoV in the ultraviolet (UV) band and a 90° wide-FoV in the visible band. After optimization, the dual-band camera design achieves a modulation transfer function (MTF) exceeding 0.7 at the 55 lp/mm cutoff frequency. The RMS spot size is less than 3 μm in the UV band and under 6 μm in the visible band, as illustrated in Figs. 7 and 8. This performance supports system miniaturization, and combines with an integrated structural design, resulting in an optical camera with a compact overall envelope of merely 30 mm×80 mm×150 mm and a mass of only 1.9 kg, as shown in Fig. 11.

This research presents an innovative optical payload configuration for deep space planetary exploration: a co-prism multispectral camera system integrating visible and ultraviolet wide-FoV imaging. The system incorporates a multispectral channel narrow-band filter array at the detection focal plane, enabling broadband multispectral imaging from 0.29 μm to 0.80 μm. The periscopic folding configuration of the shared prism achieves a compact dual-band co-focal plane layout, facilitating system miniaturization. The integrated structural design yields an optical camera with dimensions of 30 mm×80 mm×150 mm and a mass of 1.9 kg, with actual measurements being notably lower. A vector aberration analysis model is developed to achieve aberration correction across the wide spectral band and field of view. This model provides detailed analysis of aberration contributions from the shared prism structure, establishing a theoretical foundation for optical parameter design. The initial structure optimized through this model effectively meets imaging requirements while facilitating overall optical system optimization. The system offers significant implications for wide-FoV, multidimensional deep space exploration methods compatible with CubeSat payload constraints. This camera demonstrates potential for deployment in low-orbit missions around the Moon, Mars, and other planets, enabling the acquisition of large-area panoramic images with multispectral texture details. These capabilities will enhance the exploration of planetary geological characteristics and material identification, providing essential data for understanding planetary environments and identifying suitable landing sites.