Open AccessHigh dynamic range imaging by pupil single‐mode filtering and remapping
Author(s) -
Perrin G.,
Lacour S.,
Woillez J.,
Thiébaut É.
Publication year - 2006
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2006.11063.x
Subject(s) - physics , telescope , optics , high dynamic range , dynamic range , angular resolution (graph drawing) , aperture (computer memory) , interferometry , speckle pattern , speckle imaging , exit pupil , wide dynamic range , pupil , acoustics , mathematics , combinatorics
Because of atmospheric turbulence, obtaining high angular resolution images with a high dynamic range is difficult even in the near‐infrared domain of wavelengths. We propose a novel technique to overcome this issue. The fundamental idea is to apply techniques developed for long baseline interferometry to the case of a single‐aperture telescope. The pupil of the telescope is broken down into coherent subapertures each feeding a single‐mode fibre. A remapping of the exit pupil allows interfering all subapertures non‐redundantly. A diffraction‐limited image with very high dynamic range is reconstructed from the fringe pattern analysis with aperture synthesis techniques, free of speckle noise. The performances of the technique are demonstrated with simulations in the visible range with an 8‐m telescope. Raw dynamic ranges of 1:10 6 can be obtained in only a few tens of seconds of integration time for bright objects.