Optical design and precision analysis of a single-line-array pendulum sweep high-resolution mapping camera.

With the improvement of the satellite resolution, it is urgent to develop the single-line-array mapping camera. However, the camera accuracy is influenced by the satellite attitude's rapid maneuvering during the imaging process. In our study, a coaxial four-mirror optical system with a field bias with a focal length of 7050 mm, F-number of 10.8, field of view of 1.2°, and spectral range of 450-800 nm is designed. By combining mathematical modeling and ray tracing, the offset of the camera interior orientation elements caused by the misalignment of the secondary mirror is derived. The simulation results show that the maximum relative error does not exceed 2.119%. Besides, a desensitization design method based on the magnification parameter control method is proposed, and the results show that the sensitivity of camera interior orientation elements to the secondary mirror is reduced, indicating the effectiveness of the system desensitization design, which is of great significance for the improvement of camera accuracy.