English
Related papers

Related papers: Apodized Pupil Lyot Coronagraphs for Arbitrary Tel…

200 papers

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…

Solar and Stellar Astrophysics · Physics 2017-08-02 Shaela I. Jones , Joseph M. Davila , Vadim M. Uritsky

The Exo-Planet Imaging Camera and Spectrograph (EPICS) for the future 42-meter European-Extremely Large Telescope, will enable direct images, and spectra for both young and old Jupiter-mass planets in the infrared. To achieve the required…

Instrumentation and Methods for Astrophysics · Physics 2014-11-20 P. Martinez , C. Dorrer , M. Kasper

Let $\bar{P}$ be a sequence of length $2n$ in which each element of $\{1,2,...,n\}$ occurs twice. Let $P'$ be a closed curve in a closed surface $S$ having $n$ points of simple auto-intersections, inducing a 4-regular graph embedded in $S$…

Combinatorics · Mathematics 2007-05-23 Sostenes Lins , Emerson Oliveira-Lima , Valdenberg Silva

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 problem Level Planarity asks for a crossing-free drawing of a graph in the plane such that vertices are placed at prescribed y-coordinates (called levels) and such that every edge is realized as a y-monotone curve. In the variant…

Data Structures and Algorithms · Computer Science 2024-04-26 Boris Klemz , Marie Diana Sieper

Using 2 aspheric mirrors, it is possible to apodize a telescope beam without losing light or angular resolution: the output beam is produced by ``remapping'' the entrance beam to produce the desired light intensity distribution in a new…

The purpose of this paper is to present the results of a theoretical study pertaining to the feasibility of PIAA units using Deformable Mirrors. We begin by reviewing the general derivation of the design equations driving PIAA. We then show…

Instrumentation and Methods for Astrophysics · Physics 2011-11-23 Laurent Pueyo , N. Jeremy Kasdin , Alexis Carlotti , Robert Vanderbei

The specification of polishing requirements for the optics in coronagraphs dedicated to exo-planet detection requires careful and accurate optical modelling. Numerical representations of the propagation of aberrations through the system as…

Instrumentation and Methods for Astrophysics · Physics 2011-11-07 Laurent Pueyo , N. Jeremy Kasdin , Stuart Shaklan

We propose a proximal approach to deal with a class of convex variational problems involving nonlinear constraints. A large family of constraints, proven to be effective in the solution of inverse problems, can be expressed as the lower…

Numerical Analysis · Computer Science 2014-03-21 Giovanni Chierchia , Nelly Pustelnik , Jean-Christophe Pesquet , Béatrice Pesquet-Popescu

Non-line-of-sight (NLOS) imaging, recovering the hidden volume from indirect reflections, has attracted increasing attention due to its potential applications. Despite promising results, existing NLOS reconstruction approaches are…

Computer Vision and Pattern Recognition · Computer Science 2024-09-24 Shida Sun , Yue Li , Yueyi Zhang , Zhiwei Xiong

High contrast coronagraphic imaging is challenging for telescopes with central obstructions and thick spider vanes, such as the Subaru Telescope. We present in this paper the first laboratory demonstration of a high efficiency PIAA-type…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 Julien Lozi , Frantz Martinache , Olivier Guyon

Coronagraphy is an efficient technique for identifying and characterizing extra-solar planets orbiting in the habitable zone of their parent star. An important family of coronagraphs is based on amplitude or phase filters placed at an…

Instrumentation and Methods for Astrophysics · Physics 2022-08-30 Francçois Henault

Coded apertures, traditionally employed in x-ray astronomy for imaging celestial objects, are now being adapted for micro-scale applications, particularly in studying microscopic specimens with synchrotron light diffraction. In this paper,…

Signal Processing · Electrical Eng. & Systems 2024-05-22 Doğa Gürsoy , Dina Sheyfer , Michael Wojcik , Wenjun Liu , Jonathan Tischler

Directly imaging Earth-sized exoplanets with a visible-light coronagraph instrument on a space telescope will require a system that can achieve $\sim10^{-10}$ raw contrast and maintain it for the duration of observations (on the order of…

High-resolution wide field-of-view (FOV) microscopic imaging plays an essential role in various fields of biomedicine, engineering, and physical sciences. As an alternative to conventional lens-based scanning techniques, lensfree holography…

Optics · Physics 2017-06-16 Jialin Zhang , Jiasong Sun , Qian Chen , Jiaji Li , Chao Zuo

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…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 Hari Subedi , Neil T. Zimmerman , N. Jeremy Kasdin , Kathleen Cavanagh , A J Eldorado Riggs

High contrast imaging is the primary path to the direct detection and characterization of Earth-like planets around solar-type stars; a cleverly designed internal coronagraph suppresses the light from the star, revealing the elusive…

High-resolution patterning of periodic structures over large areas has several applications in science and technology. One such method, based on the long-known Talbot effect observed with diffraction gratings, is achromatic Talbot…

Applied Physics · Physics 2023-05-03 Dimitrios Kazazis , Li-Ting Tseng , Yasin Ekinci

Telescope pupil fragmentation from spiders generates specific aberrations observed at various telescopes and expected on the large telescopes under construction. This so-called island effect induces differential pistons, tips and tilts on…

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…

‹ Prev 1 3 4 5 6 7 10 Next ›