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The Nancy Grace Roman Space Telescope Coronagraph Instrument is a high-contrast imager, polarimeter, and spectrometer that will enable the study of exoplanets and circumstellar disks at visible wavelengths ($\sim$550--850~nm) at contrasts…

The basic effect of the earth's atmospheric refraction on telescope operation is the reduction of the true zenith angle to the apparent zenith angle, associated with prismatic aberrations due to the dispersion in air. If one attempts…

Astrophysics · Physics 2007-05-23 Richard J. Mathar

Grazing incidence interferometry has been applied to rough planar and cylindrical surfaces. As suitable beam splitters diffractive optical phase elements are quite common because these allow for the same test sensitivity for all surface…

Space-based stellar coronagraph instruments aim to directly image exoplanets that are a fraction of an arcsecond separation and ten billion times fainter than their host star. To achieve this, one or more deformable mirrors (DMs) are used…

We summarize the theory of coronagraphic optics, and identify a dimensionless fine-tuning parameter, F, which we use to describe the Lyot stop size in the natural units of the coronagraphic optical train and the observing wavelength. We…

Astrophysics · Physics 2009-11-06 A. Sivaramakrishnan , C. D. Koresko , R. B. Makidon , T. Berkefeld , M. J. Kuchner

In the last two decades, optical vortices carried by twisted light wavefronts have attracted a great deal of interest, providing not only new physical insights into light-matter interactions, but also a transformative platform for boosting…

Optics · Physics 2021-11-05 Chenhao Li , Stefan A. Maier , Haoran Ren

The spin angular momentum in an elliptically polarized beam of light plays several noteworthy roles in optical traps. It contributes to the linear momentum density in a non-uniform beam, and thus to the radiation pressure exerted on…

Soft Condensed Matter · Physics 2015-06-03 David B. Ruffner , David G. Grier

Coronal astronomy is by now a fairly mature discipline, with a quarter century having gone by since the detection of the first stellar X-ray coronal source (Capella), and having benefitted from a series of major orbiting observing…

Astrophysics · Physics 2009-11-07 Fabio Favata , Giuseppina Micela

Optical aberrations have been studied for centuries, placing fundamental limits on the achievable resolution in focusing and imaging. In the context of structured light, the spatial pattern is distorted in amplitude and phase, often arising…

Imaging the direct light signal from a faint exoplanet against the overwhelming glare of its host star presents one of the fundamental challenges to modern astronomical instrumentation. Achieving sufficient signal-to-noise for detection by…

Instrumentation and Methods for Astrophysics · Physics 2014-03-05 S. Lacour , P. Tuthill , J. D. Monnier , T. Kotani , L. Gauchet , P. Labeye

We present the design of a portable coronagraph, CATEcor, that incorporates a novel "shaded truss" style of external occultation and serves as a proof-of-concept for that family of coronagraphs. The shaded truss design style has the…

Instrumentation and Methods for Astrophysics · Physics 2024-06-14 Craig E. DeForest , Daniel B. Seaton , Amir Caspi , Matt Beasley , Sarah J. Davis , Nicholas F. Erickson , Sarah A. Kovac , Ritesh Patel , Anna Tosolini , Matthew J. West

State-of-the-art coronagraphs employed on extreme adaptive optics enabled instruments, are constantly improving the contrast detection limit for companions at ever closer separations to the host star. In order to constrain their properties…

Instrumentation and Methods for Astrophysics · Physics 2015-11-11 Nemanja Jovanovic , Olivier Guyon , Frantz Martinache , Prashant Pathak , Janis Hagelberg , Tomoyuki Kudo

Technological advances will allow the placement of many Terahertz detectors at the focal plane of a single telescope. For a telescope of a given diameter and wavelength of operation, there is a limit to the number of usable detectors…

Astrophysics · Physics 2007-05-23 Antony A. Stark

In the context of exoplanet detection, the performance of coronagraphs is limited by wavefront errors. To efficiently correct for these aberrations with a deformable mirror, it is mandatory to measure them using the science detector with a…

Astrophysics · Physics 2009-11-13 R. Galicher , P. Baudoz , G. Rousset

I propose a superoscillation measurement method for subdiffraction incoherent optical sources, with potential applications in astronomy, remote sensing, fluorescence microscopy, and spectroscopy. The proposal, based on coherent optical…

Quantum Physics · Physics 2022-10-10 Mankei Tsang

Electromagnetic wave lensing, a common physical phenomenon recognized in visible light for centuries, finds extensive applications in manipulating light in optical systems such as telescopes and cameras. Magnetohydrodynamic wave is a common…

Solar and Stellar Astrophysics · Physics 2024-04-19 Xinping Zhou , Yuandeng Shen , Ding Yuan , Rony Keppens , Xiaozhou Zhao , Libo Fu , Zehao Tang , Jiaoyang Wang , Chengrui Zhou

Optical coherence tomography (OCT) uses low-coherence reflectometry to obtain cross-sectional images of inhomogeneous media, such as biological tissue. OCT is particularly useful in the biomedical ea, since the imaging can be performed…

Medical Physics · Physics 2018-03-01 Takahisa Mitsui , Kenichiro Aoki

Adaptive Optics has become a key technology for the largest ground-based telescopes currently under or close to begin of construction. Adaptive optics is an indispensable component and has basically only one task, that is to operate the…

Instrumentation and Methods for Astrophysics · Physics 2019-01-24 Stefan Hippler

A major goal of proposed future space observatories, such as the Habitable World Observatory, is to directly image and characterize Earth-like planets around Sun-like stars to search for habitability signatures requiring the starlight…

Instrumentation and Methods for Astrophysics · Physics 2023-09-12 Ramya M Anche , Sebastiaan Y. Haffert , Jaren N Ashcraft , Kian Milani , Kyle Van Gorkom , Kevin Derby , Ewan S. Douglas , Maxwell A. Millar-Blanchaer

We present numerical simulations and laboratory experiments on an eight-octant phase-mask (EOPM) coronagraph. The numerical simulations suggest that an achievable contrast for the EOPM coronagraph can be greatly improved as compared to that…

Astrophysics · Physics 2009-11-13 N. Murakami , R. Uemura , N. Baba , J. Nishikawa , M. Tamura , N. Hashimoto , L. Abe
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