Model-free deflectometry for freeform optics measurement using an iterative reconstruction technique

Logan R. Graves, Heejoo Choi, Wenchuan Zhao, Chang Jin Oh, Peng Su, Tianquan Su, Dae Wook Kim

Research output: Contribution to journalArticle

5 Scopus citations


We present a novel model-free iterative data-processing approach that improves surface reconstruction accuracy for deflectometry tests of unknown surfaces. This new processing method iteratively reconstructs the surface, leading to reduced error in the final reconstructed surface. The method was implemented in a deflectometry system, and a freeform surface was tested and compared to interferometric test results. The reconstructed departure from interferometric results was reduced from 15.80 μm RMS with model-based deflectometry down to 5.20 μm RMS with the iterative technique reported here.

Original languageEnglish (US)
Pages (from-to)2110-2113
Number of pages4
JournalOptics Letters
Issue number9
Publication statusPublished - May 1 2018


ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics

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