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Related papers: Phase-Occultation Nulling Coronagraphy

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Two high performance coronagraphic approaches compatible with segmented and obstructed telescope pupils are described. Both concepts use entrance pupil amplitude apodization and a combined phase and amplitude focal plane mask to achieve…

Instrumentation and Methods for Astrophysics · Physics 2015-06-16 Olivier Guyon , Philip H. Hinz , Eric Cady , Ruslan Belikov , Frantz Martinache

High-contrast imaging in the next decade aims to image exoplanets at smaller angular separations and deeper contrasts than ever before. A problem that has recently garnered attention for telescopes equipped with high-contrast coronagraphs…

Instrumentation and Methods for Astrophysics · Physics 2024-07-01 Jaren N. Ashcraft , Ewan S. Douglas , Ramya M. Anche , Kyle Van Gorkom , Emory Jenkins , William Melby , Maxwell A. Millar-Blanchaer

The success of the Large Interferometer For Exoplanets (LIFE) space mission depends on measuring the faint mid-infrared emission spectra of exoplanets while suppressing the glare of a host star. This requires an instrument capable of…

We describe a new series of band-limited image masks for coronagraphy that are insensitive to pointing errors and other low-spatial-frequency optical aberrations. For a modest cost in throughput, these ``eighth-order'' masks would allow the…

Astrophysics · Physics 2009-11-10 Marc J. Kuchner , Justin Crepp , Jian Ge

Directly imaging Earth-like exoplanets (``exoEarths'') with a coronagraph instrument on a space telescope requires a stable wavefront with optical path differences limited to tens of picometers RMS during exposure times of a few hours.…

Polarization is a powerful remote-sensing method to investigate solar system bodies. It is an especially sensitive diagnostic tool to reveal physical properties of the bodies whose observational characteristics are governed by small…

Astrophysics · Physics 2009-11-11 S. Bagnulo , H. Boehnhardt , K. Muinonen , L. Kolokolova , I. Belskaya , M. A. Barucci

Percutaneous coronary intervention (PCI) is typically performed with image guidance using X-ray angiograms in which coronary arteries are opacified with X-ray opaque contrast agents. Interventional cardiologists typically navigate…

Image and Video Processing · Electrical Eng. & Systems 2020-01-14 Hua Ma , Ihor Smal , Joost Daemen , Theo van Walsum

A new wavefront sensing approach, derived from the successful curvature wavefront sensing concept but using a non-linear phase retrieval wavefront reconstruction scheme, is described. The non-linear curvature wavefront sensor (nlCWFS)…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 Olivier Guyon

Detection and characterization of exoplanets by direct imaging requires a coronagraph designed to deliver high contrast at small angular separation. To achieve this, an accurate control of low order aberrations, such as pointing and focus…

Instrumentation and Methods for Astrophysics · Physics 2015-06-03 Frédéric P. A. Vogt , Frantz Martinache , Olivier Guyon , Takashi Yoshikawa , Kaito Yokochi , Vincent Garrel , Taro Matsuo

The ability to characterize exoplanets by spectroscopy of their atmospheres requires direct imaging techniques to isolate planet signal from the bright stellar glare. One of the limitations with the direct detection of exoplanets, either…

Instrumentation and Methods for Astrophysics · Physics 2015-10-14 Garima Singh , Julien Lozi , Olivier Guyon , Pierre Baudoz , Nemanja Jovanovic , Frantz Martinache , Tomoyuki Kudo , Eugene Serabyn , Jonas Kuhn

Intravascular polarimetry with catheter-based polarization-sensitive optical coherence tomography (PS-OCT) complements the high-resolution structural tomograms of OCT with morphological contrast available through polarimetry. Its clinical…

We revive a cross-platform focal-plane wavefront sensing and control algorithm originally released in 1980 and show that it can provide significant contrast improvements over conventional control methods on coronagraphic instruments. Its…

Instrumentation and Methods for Astrophysics · Physics 2023-04-03 Iva Laginja , Raphaël Pourcelot

Context. In the context of direct imaging of exoplanets, coronagraphs are commonly proposed to reach the required very high contrast levels. However, wavefront aberrations induce speckles in their focal plane and limit their performance.…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Johan Mazoyer , Pierre Baudoz , Raphaël Galicher , Gérard Rousset

The vortex coronagraph is one of the most promising coronagraphs for high contrast imaging because of its simplicity, small inner working angle, high throughput, and clear off-axis discovery space. However, as with most coronagraphs,…

Instrumentation and Methods for Astrophysics · Physics 2015-05-27 Dimitri Mawet , Eugene Serabyn , J. Kent Wallace , Laurent Pueyo

The vortex coronagraph is an optical instrument that precisely removes on-axis starlight allowing for high contrast imaging at small angular separation from the star, thereby providing a crucial capability for direct detection and…

Instrumentation and Methods for Astrophysics · Physics 2015-11-04 Garreth J. Ruane , Elsa Huby , Olivier Absil , Dimitri Mawet , Christian Delacroix , Brunella Carlomagno , Grover A. Swartzlander

We present designs for fully achromatic vector Apodizing Phase Plate (vAPP) coronagraphs, that implement low polarization leakage solutions and achromatic beam-splitting, enabling observations in broadband filters. The vAPP is a pupil plane…

Instrumentation and Methods for Astrophysics · Physics 2018-11-27 Steven P. Bos , David S. Doelman , Jos de Boer , Emiel H. Por , Barnaby Norris , Michael J. Escuti , Frans Snik

The Coronagraph Instrument (CGI) for NASA's Wide Field Infrared Survey Telescope (WFIRST) will constitute a dramatic step forward for high-contrast imaging, integral field spectroscopy, and polarimetry of exoplanets and circumstellar disks,…

As part of NASA's mission to explore habitable planets orbiting nearby stars, this paper explores the detection and characterization capabilities of a 4-m space telescope plus 50-m starshade located at the Earth-Sun L2 point, a.k.a. the New…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 Margaret C. Turnbull , Tiffany Glassman , Aki Roberge , Webster Cash , Charley Noecker , Amy Lo , Brian Mason , Phil Oakley , John Bally

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…

Instrumentation and Methods for Astrophysics · Physics 2015-05-28 Francois Henault
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