Related papers: Observing inside the coronagraphic regime with opt…
The vortex coronagraph (VC) is a new generation small inner working angle (IWA) coronagraph currently offered on various 8-meter class ground-based telescopes. On these observing platforms, the current level of performance is not limited by…
Deep sub-diffraction exoplanet discovery currently lies beyond the reach of state-of-the-art direct imaging coronagraphs, which typically have an inner working angle larger than the diffraction scale. We present an experimental…
Small-angle coronagraphy is technically and scientifically appealing because it enables the use of smaller telescopes, allows covering wider wavelength ranges, and potentially increases the yield and completeness of circumstellar…
With a clear circular aperture, the vortex coronagraph perfectly cancels an on-axis point source and offers a 0.9 or 1.75 lambda/D inner working angle for topological charge 2 or 4, respectively. Current and near-future large telescopes are…
Very high dynamical range coronagraphs targeting direct exo-planet detection (10^9 - 10^10 contrast) at small angular separation (few lambda/D units) usually require an input wavefront quality on the order of ten thousandths of wavelength…
Directly imaging extrasolar planets using a monolithic optical telescope avoids many pitfalls of space interferometry and opens up the prospect of visible light studies of extrasolar planetary systems. Future astronomical missions may…
To detect Earth-like planets in the visible with a coronagraphic telescope, two major noise sources have to be overcome: the photon noise of the diffracted star light, and the speckle noise due to the star light scattered by instrumental…
Direct observation of extra-solar planets (exoplanets) is essential to understand how planetary systems were born, how they evolve, and ultimately, to identify biological signatures on these planets. However, the enormous contrast in flux…
With the recent commissioning of ground instruments such as SPHERE or GPI and future space observatories like WFIRST-AFTA, coronagraphy should probably become the most efficient tool for identifying and characterizing extra-solar planets in…
Direct imaging of exoplanets or circumstellar disk material requires extreme contrast at the 10-6 to 10-12 levels at < 100 mas angular separation from the star. Focal-plane mask (FPM) coronagraphic imaging has played a key role in this…
High-contrast imaging from space must overcome two major noise sources to successfully detect a terrestrial planet angularly close to its parent star: photon noise from diffracted star light, and speckle noise from star light scattered by…
Stellar coronagraph performance is highly sensitive to optical aberrations. In order to effectively suppress starlight for exoplanet imaging applications, low-order wavefront aberrations entering a coronagraph such as tip-tilt, defocus and…
A high contrast coronagraph is expected to provide one of the promising ways to directly observe extra-solar planets. We present the newest results of our laboratory experiment investigating "rigid" coronagraph with a binary shaped…
The Wide Field Infrared Survey Telescope (WFIRST) Coronagraph Instrument (CGI) is a high-contrast imager and integral field spectrograph that will enable the study of exoplanets and circumstellar disks at visible wavelengths. Ground-based…
In this paper are discussed the nulling and imaging properties of monolithic pupil telescopes equipped with a focal plane waveguide array, which could be envisaged as precursor space missions for future nulling interferometers or…
The use of interferometric nulling for the direct characterization of extrasolar planets is an exciting prospect, but one that faces many practical challenges when deployed on telescopes. The largest limitation is the extreme sensitivity of…
The detection of high contrast companions at small angular separation appears feasible in conventional direct images using the self-calibration properties of interferometric observable quantities. The friendly notion of closure-phase, which…
Potentially habitable planets around nearby stars less massive than solar-type stars could join targets of the spectroscopy of the planetary reflected light with future space telescopes. However, the orbits of most of these planets occur…
This study is focused on the very high dynamic imaging field, specifically the direct observation of exoplanetary systems. The coronagraph is an essential technique for suppressing the star's light, making it possible to detect an exoplanet…
Direct detection of a planet around a star in the mid-IR, requires a nulling interferometer featuring an achromatic phase shift of pi on broad range. A new concept for designing such an achromatic phase shifter is presented here. The major…