Field of View and contrast limitations of stellar interferometers. A quick review

Abstract

Field of View (FoV) and contrast limitations of stellar interferometers have been the scope of numerous publications for more than thirty years. Recently, this topic regained some interest since long-baseline terrestrial interferometers or space borne nulling interferometers are envisioned for detecting and characterizing extra-solar planets orbiting in the habitable zone of their parent star. This goal supposes to achieving sufficient contrast ratio in the high angular frequency domain, thus on the whole interferometer FoV. In this paper are reviewed some of the contrast and FoV limiting factors, including spectral bandwidth, flux mismatches, fringe tracking, telescope image quality, atmosphere seeing, optical conjugation mismatch of the telescopes pupils, influence of anamorphous optics, pupil aberrations, signal-to-noise ratio and deviations with respect to the golden rule of imaging interferometers. Finally, a tentative classification of all these factors is provided.