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Related papers: Ring-apodized vortex coronagraphs for obscured tel…

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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…

Instrumentation and Methods for Astrophysics · Physics 2017-09-11 François Hénault , Alexis Carlotti , Christophe Vérinaud

Directly imaging and characterizing Earth-like exoplanets is a tremendously difficult instrumental challenge. Present coronagraphic systems have yet to achieve the required $10^{-10}$ broadband contrast in a laboratory environment, but…

Instrumentation and Methods for Astrophysics · Physics 2019-07-10 Carl T. Coker , Stuart B. Shaklan , A J E. Riggs , Garreth Ruane

Voltage-sensitive fluorescence imaging is widely used to image action potential waves in the heart. However, while the electrical waves trigger mechanical contraction, imaging needs to be performed with pharmacologically…

Medical Physics · Physics 2026-03-12 Shrey Chowdhary , Jan Lebert , Shai Dickman , Charles Gordon , Jan Christoph

Using an optical vortex coronagraph and simple adaptive optics techniques we have made the first convincing demonstration of an optical vortex coronagraph that is coupled to a star gazing telescope. In particular we suppressed by 97% the…

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…

The Apodized Pupil Lyot Coronagraph (APLC) is a promising coronagraphic device for direct exoplanets detection on the European-Extremely Large Telescope. We present new near-IR laboratory results using binary apodizers -- the so-called…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 P. Martinez , C. Dorrer , M. Kasper , A. Boccaletti , K. Dohlen

Medical research suggests that the anterior-posterior (AP)-diameter of the inferior vena cava (IVC) and its associated temporal variation as imaged by bedside ultrasound is useful in guiding fluid resuscitation of the critically-ill…

Computer Vision and Pattern Recognition · Computer Science 2018-08-10 Ebrahim Karami , Mohamed Shehata , Andrew Smith

We present the first observations obtained with the L'-band AGPM vortex coronagraph recently installed on LBTI/LMIRCam. The AGPM (Annular Groove Phase Mask) is a vector vortex coronagraph made from diamond subwavelength gratings. It is…

Common path interferometers (CPI) are significant due to their compactness and vibration resistance. The usual challenge in CPI would arise due to a very small separation between reference and sample beams, where sending a reference beam…

Optics · Physics 2023-07-06 Pritam P Shetty , Hemalatha V , Mahalingam Babu , Jayachandra Bingi

Valley Hall photonic crystals (VPCs) offer the potential to create topological waveguides capable of guiding light through sharp bends on a chip. They can seamlessly integrate with functional components while occupying minimal space, making…

Perfect optical vortices (POVs) provide an enabling solution to address the predicament induced by the strong dependence of classical optical vortices on theirs carried topological charges. Here, a type of generalized POVs with controllable…

Optics · Physics 2019-10-18 Junjie Yu , Chaofeng Miao , Jun Wu , Changhe Zhou

One of the science drivers for the extremely large telescope (ELT) is imaging and spectroscopy of exo-solar planets located as close as 20mas to their parent star. The application requires a well thought-out design of the high contrast…

Astrophysics · Physics 2009-11-11 Natalia Yaitskova

Using an l = 1 blazed fork-hologram at the focal plane of the Asiago 122 cm telescope, we obtained optical vortices from the stellar system Rasalgethi (alpha Herculis) and from the single star Arcturus (alpha Bootis). We have analyzed the…

Optics · Physics 2010-07-21 F. Tamburini , G. Anzolin , G. Umbriaco , A. Bianchini , C. Barbieri

We study the optimization of the Apodized Pupil Lyot Coronagraph (APLC) in the context of exoplanet imaging with ground-based telescopes. The APLC combines an apodization in the pupil plane with a small Lyot mask in the focal plane of the…

Astrophysics · Physics 2009-11-13 P. Martinez , A. Boccaletti , M. Kasper , P. Baudoz , C. Cavarroc

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

The development of spaceborne coronagraphic technology is of paramount importance to the detection of habitable exoplanets in visible light. In space, coronagraphs are able to bypass the limitations imposed by the atmosphere to reach deeper…

Context. Phase-mask coronagraphy is advantageous in terms of inner working angle and discovery space. It is however still plagued by drawbacks such as sensitivity to tip-tilt errors and chromatism. A nulling stellar coronagraph based on the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 P. Bourget , N. Schuhler , D. Mawet , P. Haguenauer

Oncoming exoplanet spectro-imagers like the Planetary Camera and Spectrograph (PCS) for the Extremely Large Telescope (ELT) will aim for a new class of exoplanets, including Earth-like planets evolving around M dwarfs i.e., closer than…

Instrumentation and Methods for Astrophysics · Physics 2022-09-14 Lucie Leboulleux , Alexis Carlotti , Stéphane Curaba , Alain Delboulbé , Laurent Jocou , Thibaut Moulin , Laurence Gluck , Marie-Hélène Sztefek

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…