1 January 2001 Subnanometer digital positioning of large bodies by Fabry-Perot interferometry
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Abstract. Subnanometer distance stabilization and positioning of large optical structures is a key active control issue for future space telescopes needing picoradian precision. We present solutions and results of a leading experiment, called COSI (control optics structure interaction), aimed at investigating Fabry-Perot cavities as active optical links, capable of stiffening large and massive structures operating in a vacuum. The optical length of each cavity is actuated by a piezoelectric translator (PZT)- driven mechanism and the cavity ensemble is controlled by a model- based digital control unit. The first experiment stabilized the relative tip- tilt motion of two 6.9 kg annular plates, 0.5 m distant. A residual error, lower than 3?-1/2pm(1?), ?> 0.1 s, is achieved in the presence of severe environment noise and artificial micrometer distance variations, thus fully demonstrating the feasibility of the COSI concept and technology. © 2001 Society of Photo-Optical Instrumentation Engineers.
© (2001) Society of Photo-Optical Instrumentation Engineers (SPIE)
Fabrizio Bertinetto, Fabrizio Bertinetto, Enrico Canuto, Enrico Canuto, } "Subnanometer digital positioning of large bodies by Fabry-Perot interferometry," Optical Engineering 40(1), (1 January 2001). https://doi.org/10.1117/1.1332773 . Submission:

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