Share Email Print
cover

Proceedings Paper

Fabrication of a free-form lens with computer-controlled optical surfacing
Author(s): Zhijing Feng; Hongzhong Wu; Zhenyu Guo; Guangmu Zhao; Yunxiang Zhang
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

Though Optical lens with free-form lens (FFL) can be significantly used in optical rectification, it is very difficult to manufacture it. Computer-controlled optical surfacing technology is used to fabricate it efficiently. In the stage of figuring FFL, the component is fixed with vacuum flat sucking disk, then ground by the progressive mode while the abrasion wheel is trimmed on-line. A lapping and polishing tool that conforms to the shape of FFL is used to finish the optical mirror. Because FFL has no any constraints, general interferogram technique can not be applied to its measurement and the accuracy of three-coordinate measuring machine is too low. So a high-precision measurement method based on image conversion is developed to measure the surface. Generally speaking, the precision after forming is under tens of micron. Then the error correction technology is employed to improve surface precision. Getting input controlled variables from error dot matrix involves deconvolution. Least-square filtration is used to solve deconvolution and wavelet analysis is used to filter fringe and tip. Then the surface after error correction is measured again. So a closed loop is formed. The accuracy of optical mirror in our experiment is under 4 micrometers while Ra is under 5 nm.

Paper Details

Date Published: 6 October 2000
PDF: 8 pages
Proc. SPIE 4231, Advanced Optical Manufacturing and Testing Technology 2000, (6 October 2000); doi: 10.1117/12.402792
Show Author Affiliations
Zhijing Feng, Tsinghua Univ. (China)
Hongzhong Wu, Tsinghua Univ. (China)
Zhenyu Guo, Tsinghua Univ. (China)
Guangmu Zhao, Tsinghua Univ. (China)
Yunxiang Zhang, Tsinghua Univ. (China)


Published in SPIE Proceedings Vol. 4231:
Advanced Optical Manufacturing and Testing Technology 2000
Li Yang; Harvey M. Pollicove; Qiming Xin; James C. Wyant, Editor(s)

© SPIE. Terms of Use
Back to Top