相关论文: A Unified View of Coronagraph Image Masks
Several recent designs for planet-finding telescopes use coronagraphs operating at visible wavelengths to suppress starlight along the telescope's optical axis while transmitting any off-axis light from circumstellar material. We describe a…
An ideal coronagraph with a band-limited image mask can efficiently image off-axis sources while removing identically all of the light from an on-axis source. However, strict mask construction tolerances limit the utility of this technique…
In this paper is presented an analytical study of the azimuthal phase-mask coronagraph currently envisioned for detecting and characterizing extra-solar planets. Special emphasis is put on the physical and geometrical interpretation of the…
A multitude of coronagraphic techniques for the space-based direct detection and characterization of exo-solar terrestrial planets are actively being pursued by the astronomical community. Typical coronagraphs have internal shaped focal…
Diluted arrays of many optical apertures will be able to provide h igh-resolution snapshot images if the beams are combined according to the densified-pupil scheme. We show that the same principle can also provide coronagraphic images, for…
Detecting exoplanets and other faint sources of emitted and reflected light near a bright star requires deeply suppressing the starlight while efficiently transmitting the dim light from its surroundings. This suppression can be carried out…
We have reported previously on a new method we are developing for using image-based information to improve global coronal magnetic field models. In that work we presented early tests of the method which proved its capability to improve…
We propose a coronagraphic system with fourth-order null for off-axis segmented telescopes, which is sufficiently insensitive to the telescope pointing errors and finite angular diameter of the host star to enable high-contrast imaging of…
We propose a solution to the problem of astrometric and photometric calibration of coronagraphic images with a simple optical device which, in theory, is easy to use. Our design uses the Fraunhofer approximation of Fourier optics. Placing a…
Specific high contrast imaging instruments are mandatory to characterize circumstellar disks and exoplanets around nearby stars. Coronagraphs are commonly used in these facilities to reject the diffracted light of an observed star and…
Future instruments need efficient coronagraphs over large spectral ranges to enable broadband imaging or spectral characterization of exoplanets 1e8 fainter than their star. Several solutions were proposed. Pupil apodizers can attenuate the…
We conducted a number of multi-band coronagraph experiments using a vacuum chamber and a binary-shaped pupil mask which in principle should work at all wavelengths, in the context of the research and development on a coronagraph to observe…
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…
The realization that direct imaging of extrasolar planets could be technologically feasible within the next decade or so has inspired a great deal of recent research into high-contrast imaging. We ourselves have contributed several design…
We propose a new approach for high-contrast imaging at the diffraction limit using segmented telescopes in a modest observation bandwidth. This concept, named "spectroscopic fourth-order coronagraphy", is based on a fourth-order coronagraph…
CONTEXT: The four-quadrant phase mask stellar coronagraph, introduced by D. Rouan et al., is capable of achieving very high dynamical range imaging and was studied in the context of the direct detection of extra-solar planets. Achromatic…
We present methods for optimizing pupil and focal plane optical elements that improve the performance of vortex coronagraphs on telescopes with obstructed or segmented apertures. Phase-only and complex masks are designed for the entrance…
We present the concept of a binary shaped mask coronagraph applicable to a telescope pupil including obscuration, based on previous works on binary shaped pupil mask by \citet{Kasdin2005} and \citet{Vanderbei1999}. Solutions with…
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…
We propose a class of graded coronagraphic "amplitude" image masks for a high throughput Lyot-type coronagraph that transmits light from an annular region around an extended source and suppresses light, with extremely high ratio, from…