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Several coronagraph designs have been proposed over the last two decades to directly image exoplanets. Among these designs, the vector vortex coronagraphs provide theoretically perfect starlight cancellation along with small inner working…

Instrumentation and Methods for Astrophysics · Physics 2017-11-29 Kevin Fogarty , Laurent Pueyo , Johan Mazoyer , Mamadou N'Diaye

Modern coronagraph design relies on advanced, large-scale optimization processes that require an ever increasing amount of computational resources. In this paper, we restrict ourselves to the design of Apodized Pupil Lyot Coronagraphs…

Instrumentation and Methods for Astrophysics · Physics 2020-12-21 Emiel H. Por , Rémi Soummer , James Noss , Kathryn St. Laurent

This paper introduces a two-and multi-level phase mask design for improved depth of focus. A novel technique is proposed incorporating cubic and generalized cubic wavefront coding (WFC). The obtained system is optical-electronic requiring…

Optics · Physics 2017-07-26 Vladimir Katkovnik , Nicholas Hogasten , Karen Egiazarian

Context. Proxima Cen b is the prime target for the search of life around a nearby exoplanet by characterizing its atmosphere in reflected light. Due to the very high star/companion contrast (<1E-6), High Dispersion Coronagraphy is the most…

Instrumentation and Methods for Astrophysics · Physics 2026-01-14 N. Blind , N. Restori , B . Chazelas , C. Lovis , J. Kühn , C. Mordasini

We present here new experimental results on high contrast imaging of 10^{-7} at 4.5Lambda/D (Lambda = 0.820 microns) by combining a circular focal plane mask (coronagraph) of 2.5Lambda/D diameter and a multi-Gaussian pupil plane mask. Both…

Astrophysics · Physics 2009-11-10 Abhijit Chakraborty , Laird A. Thompson , Mike Rogosky

Future searches for biomarkers on habitable exoplanets will rely on telescope instruments that achieve extremely high contrast at small planet-to-star angular separations. Coronagraphy is a promising starlight suppression technique,…

Instrumentation and Methods for Astrophysics · Physics 2017-12-20 J. Mazoyer , L. Pueyo , M. N'Diaye , K. Fogarty , N. Zimmerman , L. Leboulleux , K. E. St. Laurent , R. Soummer , S. Shaklan , C. Norman

We study an approach to solving the phase retrieval problem as it arises in a phase-less imaging modality known as ptychography. In ptychography, small overlapping sections of an unknown sample (or signal, say $x_0\in \mathbb{C}^d$) are…

Numerical Analysis · Mathematics 2019-10-09 Brian Preskitt , Rayan Saab

In this article, we report an imaging method, termed Fourier ptychographic microscopy (FPM), which iteratively stitches together a number of variably illuminated, low-resolution intensity images in Fourier space to produce a wide-field,…

Optics · Physics 2014-05-02 Guoan Zheng , Roarke Horstmeyer , Changhuei Yang

We present recent laboratory results demonstrating high-contrast coronagraphy for the future space-based large IR/Optical/Ultraviolet telescope recommended by the Decadal Survey. The High-contrast Imager for Complex Aperture Telescopes…

Background: Electrocardiograms are indispensable for diagnosing cardiovascular diseases, yet in many settings they exist only as paper printouts stored in multiple recording layouts. Converting these images into digital signals introduces…

One possible solution to achieve high contrast direct imaging at a small inner working angle (IWA) is to use a vector vortex coronagraph (VVC), which provides a continuous helical phase ramp in the focal plane of the telescope with a phase…

Instrumentation and Methods for Astrophysics · Physics 2014-12-02 Christian Delacroix , Olivier Absil , Brunella Carlomagno , Pierre Piron , Pontus Forsberg , Mikael Karlsson , Dimitri Mawet , Serge Habraken , Jean Surdej

We study the way Lyot coronagraphs with unapodized entrance pupils respond to small, low order phase aberrations. This study is applicable to ground-based adaptive optics coronagraphs operating at 90% and higher Strehl ratios, as well as to…

Multi-beam ptychography (MBP) offers a scalable solution to improve the throughput of state-of-the-art ptychography by increasing the number of coherent beams that illuminate the sample simultaneously. However, increasing the number of…

Optics · Physics 2025-10-29 Runqing Yang , Pablo Villanueva-Perez , Maik Kahnt

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…

Phase-contrast and dark-field imaging are relatively new X-ray imaging modalities that provide additional information to conventional attenuation-based imaging. However, this new information comes at the price of a more complex acquisition…

Phase masks have numerous applications in astronomical optics, in particular related to two themes: coronography for detection and analysis of extrasolar planets or circumstellar disks, and wavefront analysis for extremely precise adaptive…

Instrumentation and Methods for Astrophysics · Physics 2018-07-27 Kjetil Dohlen

Electrocardiogram (ECG) analysis is a fundamental tool for diagnosing cardiovascular conditions, yet anomaly detection in ECG signals remains challenging due to their inherent complexity and variability. We propose Multi-scale Masked…

Machine Learning · Computer Science 2025-02-11 Ya Zhou , Yujie Yang , Jianhuang Gan , Xiangjie Li , Jing Yuan , Wei Zhao

We design and characterize phase-modulated, ultra-compact, silicon-based axilens devices that combine efficient point focusing and grating selectivity within scalable 4-level phase mask configurations. The proposed designs are polarization…

Optics · Physics 2020-03-20 Wesley A. Britton , Yuyao Chen , Fabrizio Sgrignuoli , Luca Dal Negro

The detection of molecular species in the atmospheres of earth-like exoplanets orbiting nearby stars requires an optical system that suppresses starlight and maximizes the sensitivity to the weak planet signals at small angular separations.…

Instrumentation and Methods for Astrophysics · Physics 2017-08-22 Garreth Ruane , Dimitri Mawet , Jeffrey Jewell , Stuart Shaklan

Coronagraphs of the apodized pupil and shaped pupil varieties use the Fraunhofer diffraction properties of amplitude masks to create regions of high contrast in the vicinity of a target star. Here we present a hybrid coronagraph…

Instrumentation and Methods for Astrophysics · Physics 2016-01-21 Neil T. Zimmerman , A J Eldorado Riggs , N. Jeremy Kasdin , Alexis Carlotti , Robert J. Vanderbei
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