The linear state space model of an optical remote sensing camera with an aperture of φ572 mm was established using the structural dynamics and linear state space theory. Modal reduction was carried out using the balanced reduction method. Combined with the controllable and observability matrix, the model order was reduced. To obtain the frequency response curve between the excitation input point and the response output point, we performed a frequency response analysis with the reduced state space model. The initial frequency response curve was plotted and compared with the response curves of the DC gain method and the balanced reduction method. The accuracy and rationality of the simulation analysis were verified by dynamic tests. The balanced reduction method under state space representation provides a new method for studying the dynamics of lightweight opto-mechanical structures. It can characterize the inherent properties of the system by using the reduction model and has higher computational efficiency, which is helpful to analyze the frequency response characteristics of complex linear systems quickly and accurately.

As space remote sensing technology continuously evolves toward large apertures and high resolutions, optical systems impose increasingly stringent requirements on the mass, specific stiffness, and surface figure stability of mirrors. Leveraging unparalleled design freedom, additive manufacturing (AM) technology enables the physical fabrication of complex architectures—such as topology optimization (TO), lattices, and Voronoi structures—thereby breaking through the limitations of traditional lightweight mirror designs. This review first introduces the relevant manufacturing technologies for AM space mirrors and analyzes the characteristics of metallic and ceramic materials suitable for AM, with a particular focus on the advantages and limitations of the two most widely applied core materials: AlSi10Mg and silicon carbide (SiC). Subsequently, it reviews the state of the art in AM space mirrors, organized according to their structural typologies. Furthermore, it delves into the critical post-processing technologies required to achieve high-precision surface figures and summarizes the prevailing challenges confronting AM mirrors. Finally, it outlines future research directions for AM mirrors.