Mirror Prescription Regression: A Differential Interferometric Technique

We present a remote, differential method for measuring the prescription of aspheric mirrors using null interferometry in the center-of-curvature configuration. The method requires no equipment beyond that used in a basic interferometery setup (i.e., there are no shearing elements or absolute distanc...

Full description

Saved in:
Bibliographic Details
Main Authors: Brian M. Robinson, Patrick J. Reardon, Joseph M. Geary
Format: Article
Language:English
Published: Wiley 2010-01-01
Series:International Journal of Optics
Online Access:http://dx.doi.org/10.1155/2010/201305
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We present a remote, differential method for measuring the prescription of aspheric mirrors using null interferometry in the center-of-curvature configuration. The method requires no equipment beyond that used in a basic interferometery setup (i.e., there are no shearing elements or absolute distance meters). We chose this configuration because of its widespread use. However, the method is generalizable to other configurations with an adjustment of the governing equation. The method involves taking a series of interferograms before and after small, known misalignments are applied to the mirror in the interferometry setup and calculating the prescription (e.g., radius of curvature and conic constant) of the mirror, based on these differential measurements, using a nonlinear regression. We apply this method successfully to the testing of a Space Optics Research Lab off-axis parabola with a known focal length of 152.4 mm, a diameter of 76.2 mm, and an off-axis angle of 12°.
ISSN:1687-9384
1687-9392