télescope à pupille fente

CONT: Le télescope à pupille fente fournit des images unidimensionnelles et opère en synthèse d'ouverture. En l'absence de turbulence atmosphérique, l'image focale fournie par un télescope à pupille fente est quasiment une projection unidimensionnelle de l'objet observé. Après une rotation complète autour de son axe optique, on obtient un ensemble de projections de l'objet observé qui n'est autre que la transformée de Radon de l'objet.

CONT: The interest of a ground based Slit Aperture Telescope (SAT) which operates with a long thin pupil has been underlined for applications in the field of high angular resolution observations by speckle-interferometric techniques. The SAT lies halfway between the Michelson stellar interferometer and the standard telescope with circular aperture. The authors present the principle of an image processing algorithm which could be used associated with a space-SAT for astronomical image reconstruction. A full coverage of the two dimensional Fourier plane of the astronomical object can be obtained by rotating the SAT around its optical axis. The method of image reconstruction is analogous to those used in computerized tomography and uses Fast Fourier Transform algorithm. The interest of the use of a rotating space-SAT among synthetic apertures is its capability of giving a reconstructed image of the astronomical object simultaneously in several light wavelengths, each colored image being comparable with the others for fruitful astrophysical applications.