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Test of a Slow Off-Axis Parabola at it

Published

Author(s)

R E. Parks, Christopher J. Evans, Lianzhen Shao

Abstract

We describe the interferometric testing of a slow (f/16 at the center of curvature) off-axis parabola, intended for use in an x-ray spectrometer, that uses a spherical wave front matched to the mean radius of the asphere. We find the figure error in the off-axis mirror by removing the theoretical difference between the off-axis segment and the spherical reference form the measured wave-front error. This center of curvature test is easy to perform because the spherical reference wave front has no axis and thus alignment is trivial. We confirm that the test results are the same as the double-pass null test for a parabola that uses a plane autocollimating mirror. We also determine that the off-axis section apparently warped as the result of being cut from the symmetric parent part.
Citation
Applied Optics
Volume
34(31)

Keywords

off-axis aspherics, optical testing, Zernike polynomials

Citation

Parks, R. , Evans, C. and Shao, L. (1995), Test of a Slow Off-Axis Parabola at it, Applied Optics (Accessed June 16, 2024)

Issues

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Created October 31, 1995, Updated October 12, 2021