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arXiv · 2511.11049

Surface figure metrology for reflective membrane mirrors based on phase-measuring deflectometry

Xin Yan·Zhi-Kang Zhuang·Fu-Jia Du·Wen Duan·Peilin Yin·Mo-Nong Yu·Guang Yang
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Abstract

Reflective membrane mirrors provide a lightweight, low-cost alternative to traditional optics for next-generation large-aperture telescopes, but their non-rigid, thin structure poses challenges for surface metrology. We present a phase-measuring deflectometry (PMD) system enhanced with tailored ray-tracing and iterative reconstruction to enable non-contact measurement of large membrane optics. The system successfully characterizes the surface figure and evaluates the dynamic stability of a 1-meter Hencky-type membrane mirror. Our results demonstrate the effectiveness of PMD as a practical metrology tool for future membrane-based telescope systems.

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Xin Yan, Zhi-Kang Zhuang, Fu-Jia Du, Wen Duan, Peilin Yin, Mo-Nong Yu, Guang Yang. 2025-11-14. Surface figure metrology for reflective membrane mirrors based on phase-measuring deflectometry. https://arxiv.org/abs/2511.11049

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