Efficient testing of segmented aspherical mirrors by use of a reference plate and computer-generated holograms. II. Case study, error analysis, and experimental validation

Feenix Y. Pan, James H Burge, Dave Anderson, Alexander Poleshchuk

Research output: Contribution to journalArticle

7 Scopus citations


Segmented mirrors present unique challenges to fabrication and testing that are absent for monolithic optics. Since traditional asphere tests do not address segmented optics adequately, we validate a previously developed method to test large quantities of segments accurately, quickly, and economically. In this test, the aspheric shape of each segment is controlled to high accuracy by use of computergenerated holograms, and the radius of curvature is tightly controlled by use of the reference plate. In an adjoining paper [Appl Opt 43, 5303 (2004)] we developed the theory for this test, and now we present a complete system design and optimization for measuring the 1.4-m segments from a 30-m F/1 primary. A complete tolerance analysis predicts a test accuracy of 4.8-nm rms surface and excellent accuracy for controlling the geometry of the segment. In addition, a laboratory demonstration using 30-cm optics is presented that demonstrated 3.9-nm rms surface accuracy.

Original languageEnglish (US)
Pages (from-to)5313-5322
Number of pages10
JournalApplied Optics
Issue number28
Publication statusPublished - Oct 1 2004


ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics

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