中国科学院南京天文光学技术研究所机构知识库

As demand for high-precision optical mirrors in astronomy increases,combined fabrication using multiple polishing tool sizes has been adopted widely.To address remain ing limitations in computational and fabrication efficiency,this paper proposes an iterative wavelet-transform-based surface decomposition algorithm(IWTSD)and an associated multi-tool fabrication strategy.IWTSD applies the two-dimensional dual-tree complex wavelet trans form(2D-DTCWT)with iterative refinement to decompose a target surface into two or more scale-separated,non-negative component surfaces.Specific surface extension operation with an optimized factor is used to adapt IWTSD for non-rectangular apertures.This decomposition reduces both computational cost and total polishing dwell time compared with similar methods. Simulations demonstrate that IWTSD-based multi-tool fabrication achieves comparable surface error convergence using only 2/3 of the dwell time required by other multi-tool fabrication based on alternative surface decomposition algorithms,and yields a residual RMS about 1/3 that of single-tool fabrication.Experimental polishing of a 1150 mm off-axis aspheric mirror showed that overall RMS decreased from 0.655λto 0.21λ,and residuals at each scale were substantially reduced.These results demonstrate that the proposed method can improve fabrication efficiency for large-aperture optical mirrors with low computational cost.