Support of thin-meniscus primary for SOFIA

Hans-Juergen Meier

doi:10.1117/12.23043

1 November 1990 Support of thin-meniscus primary for SOFIA

Hans-Juergen Meier

Proceedings Volume 1340, Cryogenic Optical Systems and Instruments IV; (1990) https://doi.org/10.1117/12.23043
Event: 34th Annual International Technical Symposium on Optical and Optoelectronic Applied Science and Engineering, 1990, San Diego, CA, United States

Abstract

The thin meniscus for SOFIA has reduced weight at the cost of mirror stiffness. As this stiffness is reduced, the support system becomes more complicated in order to hold the mirror in the required optical shape regardless of the deformation of the supporting cell structure. The coupling between mirror cell and meniscus is equivalent to a kind of whiffle tree, which reduces its large number of axial support points down to exactly three points, eliminating any mirror deformation. This reduction system is verified for SOFIA by a hydraulic axial support system for 64 support points in an optimized arrangement in four support rings. Contour line plots and the optical performance are given for this system. A dynamic analysis of the mirror and its support system has shown a remarkable insensitivity of the system against axial accelerations. This mechanism is studied and explained using a simplified beam model. The lateral support system does not carry the mirror at the outer rim as usually designed, but at the mirror's rear side in combination with the axial support system. All the lateral support forces are momentum compensated to transfer the actual force position into the flexural neutral line of the mirror. The self balancing hydraulic support system can be superposed by an active correction system, which adds forces generated by a lever system with a motor driven dead weight. This system can be used to correct long wave errors of the mirror or flight related shape errors of time independent behavior.

Citation Download Citation

Hans-Juergen Meier "Support of thin-meniscus primary for SOFIA", Proc. SPIE 1340, Cryogenic Optical Systems and Instruments IV, (1 November 1990); https://doi.org/10.1117/12.23043

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available