Design strategy and tolerance analysis of laser arrays for telescope system alignment

To address the alignment challenges of large-aperture telescopes in extreme environments such as Antarctica, this study presents a design strategy for a laser array that exploits the correlation between aperture position and optical aberration to reduce system complexity. Under this strategy, a double-ring laser array is employed to reconstruct wavefront aberration by calculating the centroid offset of defocused spots, achieving an accuracy of λ/14. The defocus distance is critical for accuracy. Simulation results indicate a linear relationship between the optimal defocus distance and the system's focal ratio. Following the determination of the optimal defocus distance, the integrated method was applied to a 1-meter aperture, F/7 Ritchey-Chrétien (R-C) telescope as a specific case study to assess the robustness and precision, a Monte Carlo simulation was performed to analyze contributing error sources, including laser pointing (σ₁=0.075λ), wavefront reconstruction (σ₂=0.07λ), and environmental interference (σ₃= 0.005λ). The combined system error was estimated to be approximately 0.1λ. By analyzing the geometric distortion of defocused spot patterns, the proposed method enables rapid measurement of low-order aberrations, thereby offering a robust and convenient solution for the efficient alignment and maintenance of telescopes in complex field environments.