First images on the sky from a hyper telescope^*

¹ Collège de France, 11 place Marcelin Berthelot, F-75231 Paris Cedex 05, France
² Observatoire de Haute Provence, CNRS, F-04870 Saint Michel l'Observatoire, France
³ Observatoire de la Côte d'Azur, Département Fresnel, ISA-GI2T, F-06108 Saint Vallier de Thiey, France
⁴ DESPA, Observatoire de Paris-Meudon, 5 place J. Janssen, F-92195 Meudon, France

Send offprint request to: E. Pedretti, e-mail: pedretti@obs-hp.fr

Received: 28 April 2000
Accepted: 8 September 2000

Abstract

We show star images obtained with a miniature “densified pupil imaging interferometer” also called a hyper-telescope. The formation of such images violates a “golden rule of imaging interferometers” which appeared to forbid the use of interferometric arrangements differing from a Fizeau interferometer. These produce useless images when the sub-apertures spacing is much wider than their size, owing to diffraction through the sub-apertures. The hyper-telescope arrangement solves these problems opening the way towards multi-kilometer imaging arrays in space. We experimentally obtain an intensity gain of when a densified-pupil interferometer is compared to an equivalent Fizeau-type interferometer and show images of the double star  Gem. The initial results presented confirm the possibility of directly obtaining high resolution and high dynamic range images in the recombined focal plane of a large interferometer if enough elements are used.