Share Email Print

Proceedings Paper

Non-null interferometer for measurement of aspheric transmitted wavefronts
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Testing in a non-null manner causes the test and reference rays in the interferometer to follow different optical paths through the system. The retrace errors generated by this difference are test dependent and must be calibrated independently for each test piece. Optical design software can be used to perform reverse optimization of the interferometer and data. An iterative reverse optimization process has been developed which eliminates weighting sensitivity and improves optimization efficiency. However, implementation of reverse optimization generates constraints on the interferometer design. These include constraints on lens parameters, system apertures, and component verification considerations. A Mach-Zehnder interferometer has been built for non-null transmitted aspheric wavefront testing. The large aspheric departures and steep wavefront slopes are detected and reconstructed using Sub-Nyquist interferometry (SNI). Experiments on several test parts were performed to verify the iterative reverse optimization process and extend the use of SNI to non-rotationally symmetric aspheric wavefronts. Wavefront departures up to 200λ were characterized to λ/6 PV and λ/47 rms. The reverse optimization process was shown to remove up to 25λ of induced aberration from an aspheric measurement. The results indicate potential for application of the iterative method and its associated design constraints to routine aspheric testing.

Paper Details

Date Published: 22 December 2003
PDF: 12 pages
Proc. SPIE 5180, Optical Manufacturing and Testing V, (22 December 2003); doi: 10.1117/12.506047
Show Author Affiliations
Robert O. Gappinger, Jet Propulsion Lab. (United States)
John E. Greivenkamp, Optical Sciences Ctr./Univ. of Arizona (United States)

Published in SPIE Proceedings Vol. 5180:
Optical Manufacturing and Testing V
H. Philip Stahl, Editor(s)

© SPIE. Terms of Use
Back to Top