Share Email Print

Proceedings Paper

Techniques and uncertainty analysis for interferometric surface figure error measurement of spherical mirrors at 20K
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

This report describes the facility and experimental methods at the Goddard Space Flight Center Optics Branch for the measurement of the surface figure of cryogenically-cooled spherical mirrors using standard phase-shifting interferometry, with an uncertainty goal of 6 nm rms. The mirrors to be tested will be spheres with radius of curvature of 600 mm, and clear apertures of 120 - 150 mm. The optic surface will first be measured at room temperature using standard "absolute" techniques with an uncertainty of 2.6 nm rms; and then the change in surface figure error between room temperature and 20 K will be measured with an uncertainty goal of 5.4 nm rms. The mirror will be cooled within a cryostat, and its surface figure error measured through a fused-silica window. The facility and techniques are being developed to measure the cryogenic surface figure error of prototype lightweight mirrors being developed by the European Space Agency (ESA) and by US companies in SBIR's for NASA. This paper will present the measurement facility, methods and uncertainty analysis.

Paper Details

Date Published: 22 December 2003
PDF: 11 pages
Proc. SPIE 5180, Optical Manufacturing and Testing V, (22 December 2003); doi: 10.1117/12.508300
Show Author Affiliations
Peter N. Blake, NASA Goddard Space Flight Ctr. (United States)
Ronald G. Mink, NASA Goddard Space Flight Ctr. (United States)
David Content, NASA Goddard Space Flight Ctr. (United States)
Pamela Davila, NASA Goddard Space Flight Ctr. (United States)
Frederick David Robinson, NASA Goddard Space Flight Ctr. (United States)
Orbital Sciences Corp. (United States)
Scott R. Antonille, NASA Goddard Space Flight Ctr. (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