A Caltech Library Service

Multilayer Active Shell Mirrors for Space Telescopes

Steeves, John and Jackson, Kathryn and Pellegrino, Sergio and Redding, David and Wallace, J. Kent and Bradford, Samuel Case and Barbee, Troy (2016) Multilayer Active Shell Mirrors for Space Telescopes. In: Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation II. No.9912. Society of Photo-Optical Instrumentation Engineers (SPIE) , Bellingham, WA, Art. No. 99121K. ISBN 9781510602038.

[img] PDF - Published Version
See Usage Policy.


Use this Persistent URL to link to this item:


A novel active mirror technology based on carbon fiber reinforced polymer (CFRP) substrates and replication techniques has been developed. Multiple additional layers are implemented into the design serving various functions. Nanolaminate metal films are used to provide a high quality reflective front surface. A backing layer of thin active material is implemented to provide the surface-parallel actuation scheme. Printed electronics are used to create a custom electrode pattern and flexible routing layer. Mirrors of this design are thin (< 1.0 mm), lightweight (2.7 kg/m^2), and have large actuation capabilities. These capabilities, along with the associated manufacturing processes, represent a significant change in design compared to traditional optics. Such mirrors could be used as lightweight primaries for small CubeSat-based telescopes or as meter-class segments for future large aperture observatories. Multiple mirrors can be produced under identical conditions enabling a substantial reduction in manufacturing cost and complexity. An overview of the mirror design and manufacturing processes is presented. Predictions on the actuation performance have been made through finite element simulations demonstrating correctabilities on the order of 250-300× for astigmatic modes with only 41 independent actuators. A description of the custom metrology system used to characterize the active mirrors is also presented. The system is based on a Reverse Hartmann test and can accommodate extremely large deviations in mirror figure (> 100 μm PV) down to sub-micron precision. The system has been validated against several traditional techniques including photogrammetry and interferometry. The mirror performance has been characterized using this system, as well as closed-loop figure correction experiments on 150 mm dia. prototypes. The mirrors have demonstrated post-correction figure accuracies of 200 nm RMS (two dead actuators limiting performance).

Item Type:Book Section
Related URLs:
URLURL TypeDescription
Pellegrino, Sergio0000-0001-9373-3278
Additional Information:© 2016 Society of Photo-Optical Instrumentation Engineers (SPIE). A part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology under a contract with the National Aeronautics and Space Administration (NASA).
Funding AgencyGrant Number
Subject Keywords:Active Mirrors, CFRP, Nanolaminate, Replication, Reverse Hartmann
Issue or Number:9912
Record Number:CaltechAUTHORS:20160929-102853368
Persistent URL:
Official Citation:John Steeves ; Kathryn Jackson ; Sergio Pellegrino ; David Redding ; J. Kent Wallace ; Samuel Case Bradford and Troy Barbee " Multilayer active shell mirrors for space telescopes ", Proc. SPIE 9912, Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation II, 99121K (July 22, 2016); doi:10.1117/12.2233594;
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:70658
Deposited By: Ruth Sustaita
Deposited On:29 Sep 2016 18:30
Last Modified:03 Oct 2019 16:00

Repository Staff Only: item control page