# Coronographie à masque de phase: applications aux télescopes et interféromètres au sol et dans l'espace

Abstract : In this thesis work a complete study of the four quadrants coronagraph is presented. This new coronagraph offers performances of extremely large theorical rejection factor (>10^6). These performances open possibilities of exo-planets detection around nearby stars. The first laboratory results gave an attenuation rate higher than 90000 on the central peak. Thus, I naturally studied all the possible uses of this coronagraph on ground-based as well as on the space telescopes. On the former, this device can be used, coupled with high order adaptive optics for detection of brown dwarves and hot giant planets around the closest stars. On the latter, I focalized my interest on the MIRI instrument (Mid InfraRed Imager) for the NGST telescope, and on a space interferometer (for Terrestrial Planet Finder'') of NASA. Numerical simulations are presented within the framework of the Planet Finder'' ESO project. Nevertheless, an important problem must be solved: the chromatism of \pi phase-shift. Thus, I will present three solutions leading to the achromatisation of the coronagraph.
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Document type :
Theses

https://tel.archives-ouvertes.fr/tel-00004234
Contributor : Pierre Riaud <>
Submitted on : Tuesday, January 20, 2004 - 3:27:52 PM
Last modification on : Thursday, December 10, 2020 - 11:09:09 AM
Long-term archiving on: : Monday, September 17, 2012 - 3:20:47 PM

### Identifiers

• HAL Id : tel-00004234, version 1

### Citation

Pierre Riaud. Coronographie à masque de phase: applications aux télescopes et interféromètres au sol et dans l'espace. Astrophysique [astro-ph]. Université Pierre et Marie Curie - Paris VI, 2003. Français. ⟨tel-00004234⟩

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