Liu, Y, Chen, Z, Yang, Z et al. (2 more authors) (2016) An inline surface measurement method for membrane mirror fabrication using two-stage trained Zernike polynomials and elitist teaching–learning-based optimization. Measurement Science and Technology, 27 (12). 124005. ISSN 0957-0233
Abstract
The accuracy of surface measurement determines the manufacturing quality of membrane mirrors. Thus, an efficient and accurate measuring method is critical in membrane mirror fabrication. This paper formulates this measurement issue as a surface reconstruction problem and employs two-stage trained Zernike polynomials as an inline measuring tool to solve the optical surface measurement problem in the membrane mirror manufacturing process. First, all terms of the Zernike polynomial are generated and projected to a non-circular region as the candidate model pool. The training data are calculated according to the measured values of distance sensors and the geometrical relationship between the ideal surface and the installed sensors. Then the terms are selected by minimizing the cost function each time successively. To avoid the problem of ill-conditioned matrix inversion by the least squares method, the coefficient of each model term is achieved by modified elitist teaching–learning-based optimization. Subsequently, the measurement precision is further improved by a second stage of model refinement. Finally, every point on the membrane surface can be measured according to this model, providing more the subtle feedback information needed for the precise control of membrane mirror fabrication. Experimental results confirm that the proposed method is effective in a membrane mirror manufacturing system driven by negative pressure, and the measurement accuracy can achieve 15 µm.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2016 IOP Publishing Ltd. Original content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. To view a copy of this license, visit https://creativecommons.org/licenses/by/3.0/. |
Keywords: | inline measurement; forward model selection; model refinement; heuristic optimization; Zernike polynomials; non-circular region; elitist TLBO |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Electronic & Electrical Engineering (Leeds) > Institute of Communication & Power Networks (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 26 Nov 2018 10:37 |
Last Modified: | 26 Nov 2018 10:37 |
Status: | Published |
Publisher: | IOP Publishing |
Identification Number: | 10.1088/0957-0233/27/12/124005 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:139098 |