Error analysis and optimization of a dual-output beams optical system assembled using a serial-parallel hybrid platform

Optical path folding is an effective strategy for miniaturizing precision optical systems. However, it substantially increases the system’s sensitivity to machining and assembly errors. This paper proposes a system-level error modeling and optimization framework for a folded-path optical system assembled using a serial-parallel hybrid motion platform. An error model of the hybrid platform is established based on adjoint transformation theory. Furthermore, a generalized model of optical system accuracy, incorporating the machining deviations of optical element adjustment mounts and the assembly errors of optical components, is developed using homogeneous coordinate transformation. A numerical simulation algorithm based on the Monte Carlo method is introduced to analyze the effects of machining and assembly errors on the system’s output accuracy under different conditions. To balance output precision and manufacturing feasibility, a Monte Carlo-based multi-objective optimization strategy is employed to theoretically optimize the machining deviations of the optical element adjustment mounts. Experimental validation conducted under specified machining and assembly error conditions shows a maximum deviation of 10.3% between the measured and simulated results, thereby confirming the predictive accuracy of the proposed model. The proposed systematic error modeling and process-constrained optimization methodology provides both theoretical guidance and practical reference for the design and assembly of precision optical systems, enabling reverse derivation of design parameters from performance targets as well as prediction of system performance based on actual manufacturing errors.