5 Conclusion

In this paper, we have presented a laboratory interferometer developed to obtain high contrast fringe patterns, and we demonstrate the validity of high extinction nulling interferometry in a monochromatic case.

This interferometer has been built. The first measurements exhibit extinction levels never before reached in this spectral range. This performance was obtained by the implementation of an optical filtering device whose principle had already been shown by numerical simulations, but had not previously been demonstrated in this wavelength range.

The next step is the development of existing setups, with the goal of demonstrating interferometric extinction for the polychromatic case. Then the development of an instrument that can be adapted to a ground-based interferometer, the Large Binocular Telescope (LBT) or the Very Large Telescope Interferometer (VLTI) for instance, can be considered.

Acknowledgements

The authors are very grateful to their colleagues, who took part in the definition and realization of the experiment. Special thanks to Patrick Bouchareine and Thierry Lépine from the Institut d'Optique Théorique et Appliquée in Orsay, Guy Artzner, Michel Decaudin, Patrick Boumier, Denis Barbet, Fernand Sarriau and Bruno Crâne from the Institut d'Astrophysique Spatiale in Orsay, Jean Gay and Yves Rabbia from the Observatoire de la Côte d'Azur, Vincent Coudé du Foresto, Guy Perrin, Bertrand Mennesson, Pascal Bordé and Patrick Dierich from the Département d'Études Spatiales in Meudon, Pierre-Olivier Lagage from the Service d'Astrophysique du CEA in Saclay, Fabien Malbet and Pascal Puget from the Laboratoire d'Astrophysique de l'Observatoire de Grenoble. The authors want to thank also Christian Chardonnet, Anne Amy-Klein and Alain Vanlerberghe from the Laboratoire de Physique des Lasers in Villetaneuse and Mr. Courtois from the Groupe de Spectrométrie Moléculaire de l'Université de Reims for their help in the field of CO₂ lasers.

This work was supported by the Centre National d'Études Spatiales (CNES), the Centre National de la Recherche Scientifique (CNRS), the Université de Paris-Sud and the European Space Agency (ESA).