Off-Axial Three-Mirror System With Integrated Freeform Mirrors

The patent merges the primary mirror and tertiary mirror into a single integrated component with a freeform surface. This combination eliminates the need for separate assembly and alignment of these two mirrors, directly resolving the contradiction by reducing assembly complexity while maintaining the optical functionality of both mirrors. The integrated design allows the system to benefit from simpler manufacturing of the combined structure while avoiding the alignment difficulties that would arise from using separate mirrors.

The patent employs a freeform surface described by mathematical polynomials (such as Zernike or XY polynomials) for the integrated mirror. This allows continuous adjustment of surface parameters and coefficients to optimize imaging performance across multiple fields of view. The freeform surface provides numerous adjustable parameters that enable fine-tuning of optical paths, thereby increasing degrees of freedom for imaging optimization while remaining manufacturable through precision polishing and measurement techniques.

By integrating the primary and tertiary mirrors into a single component, the patent eliminates alignment errors that would occur between separate mirrors. The integrated design ensures that the optical surfaces are precisely positioned relative to each other during manufacturing, achieving higher system alignment precision. At the same time, the freeform surface allows independent optimization of different regions of the mirror to maintain individual mirror optimization benefits.