Abstract

Traditional high-precision optical techniques, such as interferometry, are in ever-greater demand for noncontrolled environments. This is the case for the UPC-ZEBRA, a large-aperture interferometer that was built to measure vertical discontinuities (i.e., piston errors) in segmented mirrors. The large mechanical systems used to drive the interferometer to the different measurement positions generate perturbations that are highly incompatible with the expected piston measurements on the nanometer scale. We introduce a new system based on a line-scan CCD to track interference fringes. The error signal obtained from this fringe tracker has been used in a closed-loop control system to actively stabilize the interferometer. The perturbation has been attenuated by a factor of $1/200$.

© 2006 Optical Society of America

Testing and applicability of the UPC-ZEBRA interferometer as a phasing system in segmented-mirror telescopes

Agustı́ Pintó, Ferran Laguarta, Roger Artigas, and Cristina Cadevall
Appl. Opt. 43(5) 1091-1096 (2004)

Robust determination of optical path difference: fringe tracking at the Infrared Optical Telescope Array interferometer

Ettore Pedretti, Wesley A. Traub, John D. Monnier, Rafael Millan-Gabet, Nathaniel P. Carleton, F. Peter Schloerb, Michael K. Brewer, Jean-Philippe Berger, Marc G. Lacasse, and Sam Ragland
Appl. Opt. 44(25) 5173-5179 (2005)

Dual-wavelength low-coherence instantaneous phase-shifting interferometer to measure the shape of a segmented mirror with subnanometer precision

Rainer Wilhelm, Bruno Luong, Alain Courteville, Sébastien Estival, Frédéric Gonté, and Nicolas Schuhler
Appl. Opt. 47(29) 5473-5491 (2008)

Experimental results on piston detection by using the classical Ronchi test

Javier Salinas-Luna, Esteban Luna, Luis Salas, and Juan Nunez
Appl. Opt. 45(27) 6990-6997 (2006)

Dispersion in stellar interferometry: simultaneous optimization for delay tracking and visibility measurements

John Davis, William J. Tango, and Erik D. Thorvaldson
Appl. Opt. 37(22) 5132-5136 (1998)