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Gaussian aperture pupil masks (GAPMs) can in theory achieve the contrast requisite for directly imaging an extrasolar planet. We outline the process of fabricating and testing a GAPM for use on the Penn State near-IR Imager and Spectrograph…

Astrophysics · Physics 2007-05-23 J. H. Debes , J. Ge , C. Mendelowitz , A. Watson

The current generation of ground-based coronagraphic instruments uses deformable mirrors to correct for phase errors and to improve contrast levels at small angular separations. Improving these techniques, several space and ground based…

Instrumentation and Methods for Astrophysics · Physics 2017-10-11 Johan Mazoyer , Laurent Pueyo , Mamadou N'Diaye , Dimitri Mawet , Rémi Soummer , Colin Norman

Recently, a method of recording holograms of coherently illuminated three-dimensional scene without two-wave interference was demonstrated. The method is an extension of the coded aperture correlation holography from incoherent to coherent…

Optics · Physics 2023-07-19 Nathaniel Hai , Joseph Rosen

Future large segmented space telescopes and their coronagraphic instruments are expected to provide the resolution and sensitivity to observe Earth-like planets with a 10^10 contrast ratio at less than 100 mas from their host star. Advanced…

The unparalleled theoretical performance of an ideal vector vortex coronagraph makes it one of the most promising technologies for directly imaging exoplanets with a future, off-axis space telescope. However, the image contrast required for…

Instrumentation and Methods for Astrophysics · Physics 2023-06-23 Garreth Ruane , A J Eldorado Riggs , Eugene Serabyn , Wesley Baxter , Camilo Mejia Prada , Dimitri Mawet , Matthew Noyes , Phillip K. Poon , Nelson Tabiryan

The Enhanced Resolution Imager and Spectrograph (ERIS) is the new near-infrared instrument at the VLT-UT4. ERIS replaces and extends the observational capabilities formerly provided by SINFONI and NACO: integral field spectroscopy at 1 -…

The design and implementation of a multiplexed spiral phase mask in an experimental optical tweezer setup are presented. This diffractive optical element allows the generation of multiple concentric vortex beams with independent topological…

The Optimal Optical Coronagraph (OOC) Workshop at the Lorentz Center in September 2017 in Leiden, the Netherlands gathered a diverse group of 25 researchers working on exoplanet instrumentation to stimulate the emergence and sharing of new…

Segmented telescopes are a possibility to enable large-aperture space telescopes for the direct imaging and spectroscopy of habitable worlds. However, the complexity of their aperture geometry, due to the central obstruction, support…

We present a design strategy for selecting the effective polarizability distribution for a metasurface aperture needed to form a desired radiation pattern. A metasurface aperture consists of an array of subwavelength metamaterial elements,…

In diffraction imaging, one is tasked with reconstructing a signal from its power spectrum. To resolve the ambiguity in this inverse problem, one might invoke prior knowledge about the signal, but phase retrieval algorithms in this vein…

Functional Analysis · Mathematics 2013-06-26 Afonso S. Bandeira , Yutong Chen , Dustin G. Mixon

In recent years, phase mask coronagraphy has become increasingly efficient in imaging the close environment of stars, enabling the search for exoplanets and circumstellar disks. Coronagraphs are ideally suited instruments, characterized by…

Instrumentation and Methods for Astrophysics · Physics 2014-12-02 Christian Delacroix , Oliver Absil , Dimitri Mawet , Charles Hanot , Mikael Karlsson , Pontus Forsberg , Eric Pantin , Jean Surdej , Serge Habraken

There is growing interest in the use of coded aperture imaging systems for a variety of applications. Using an analysis framework based on mutual information, we examine the fundamental limits of such systems---and the associated optimum…

Image and Video Processing · Electrical Eng. & Systems 2017-12-14 Adam Yedidia , Christos Thrampoulidis , Gregory Wornell

The new frontier in the quest for the highest contrast levels in the focal plane of a coronagraph is now the correction of the large diffractive artifacts effects introduced at the science camera by apertures of increasing complexity. The…

Instrumentation and Methods for Astrophysics · Physics 2016-01-18 Johan Mazoyer , Laurent Pueyo , Colin Norman , Mamadou N'Diaye , Roeland P. van der Marel , Rémi Soummer

We present a new method to achieve high-contrast images using segmented and/or on-axis telescopes. Our approach relies on using two sequential Deformable Mirrors to compensate for the large amplitude excursions in the telescope aperture due…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Laurent Pueyo , Colin Norman

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…

Astrophysics · Physics 2009-10-31 A. Boccaletti , P. Riaud , C. Moutou , A. Labeyrie

Traditional face masks used extensively, for example, during the COVID-19 pandemic, are relatively impermeable, forcing aerosol-containing breath to flow into the surrounding atmosphere by ``leaking" out from the lateral edges of the mask.…

In this article we show that the vector-Apodizing Phase Plate (vAPP) coronagraph can be designed such that the coronagraphic point spread functions (PSFs) can act as a wavefront sensor to measure and correct the (quasi-)static aberrations,…

Instrumentation and Methods for Astrophysics · Physics 2019-11-27 Steven P. Bos , David S. Doelman , Julien Lozi , Olivier Guyon , Christoph U. Keller , Kelsey L. Miller , Nemanja Jovanovic , Frantz Martinache , Frans Snik

Extra-solar planets have not been imaged directly with existing ground or space telescopes because they are too faint to be seen against the halo of the nearby bright star. Most techniques being explored to suppress the halo are achromatic,…

Astrophysics · Physics 2009-11-10 Johanan L. Codona , Roger Angel

The evanescent wave coronagraph uses the principle of frustrated total internal reflection (FTIR) to suppress the light coming from the star and study its close environment. Its focal plane mask is composed of a lens and a prism placed in…

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