Precise determination of the zero-gravity surface figure of a mirror without gravity-sag modeling
Applied Optics, Vol. 46, Issue 31, pp. 7670-7678 (2007)
http://dx.doi.org/10.1364/AO.46.007670
Enhanced HTML
Acrobat PDF (1730 KB)
Abstract
The zero-gravity surface figure of optics used in spaceborne astronomical instruments must be known to high accuracy, but earthbound metrology is typically corrupted by gravity sag. Generally, inference of the zero-gravity surface figure from a measurement made under normal gravity requires finite-element analysis (FEA), and for accurate results the mount forces must be well characterized. We describe how to infer the zero-gravity surface figure very precisely using the alternative classical technique of averaging pairs of measurements made with the direction of gravity reversed. We show that mount forces as well as gravity must be reversed between the two measurements and discuss how the St. Venant principle determines when a reversed mount force may be considered to be applied at the same place in the two orientations. Our approach requires no finite-element modeling and no detailed knowledge of mount forces other than the fact that they reverse and are applied at the same point in each orientation. If mount schemes are suitably chosen, zero-gravity optical surfaces may be inferred much more simply and more accurately than with FEA.
© 2007 Optical Society of America
OCIS Codes
(000.2780) General : Gravity
(120.6650) Instrumentation, measurement, and metrology : Surface measurements, figure
(220.4840) Optical design and fabrication : Testing
ToC Category:
Instrumentation, Measurement, and Metrology
History
Original Manuscript: June 29, 2007
Manuscript Accepted: August 10, 2007
Published: October 25, 2007
Citation
Eric E. Bloemhof, Jonathan C. Lam, V. Alfonso Feria, and Zensheu Chang, "Precise determination of the zero-gravity surface figure of a mirror without gravity-sag modeling," Appl. Opt. 46, 7670-7678 (2007)
http://www.opticsinfobase.org/ao/abstract.cfm?URI=ao-46-31-7670
You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.
Contact your librarian or system administrator
or
Log in to access OSA Member Subscription
You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.
Contact your librarian or system administrator
or
Log in to access OSA Member Subscription
You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.
Contact your librarian or system administrator
or
Log in to access OSA Member Subscription
You do not have subscription access to this journal. Article level metrics are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.
Contact your librarian or system administrator
or
Log in to access OSA Member Subscription





OSA is a member of 