English
Related papers

Related papers: Obstructed Telescopes vs Unobstructed Telescopes f…

200 papers

A long-standing challenge in multiple-particle-tracking is the accurate and precise 3D localization of individual particles at close proximity. One established approach for snapshot 3D imaging is point-spread-function (PSF) engineering, in…

Image and Video Processing · Electrical Eng. & Systems 2020-10-01 Elias Nehme , Boris Ferdman , Lucien E. Weiss , Tal Naor , Daniel Freedman , Tomer Michaeli , Yoav Shechtman

A main science goal for the Large Synoptic Survey Telescope (LSST) is to measure the cosmic shear signal from weak lensing to extreme accuracy. One difficulty, however, is that with the short exposure time ($\simeq$15 seconds) proposed, the…

Axially symmetric telescopes produce well known "Seidel" off-axis third-order aberration patterns: coma, astigmatism, curvature of field and distortion. When axial symmetry is broken by the small misalignments of optical elements,…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 Paul L. Schechter , Rebecca Sobel Levinson

Conventional image reconstruction models for lensless cameras often assume that each measurement results from convolving a given scene with a single experimentally measured point-spread function. These image reconstruction models fall short…

Computer Vision and Pattern Recognition · Computer Science 2022-12-21 Oliver Kingshott , Nick Antipa , Emrah Bostan , Kaan Akşit

Measuring a weak gravitational lensing signal to the level required by the next generation of space-based surveys demands exquisite reconstruction of the point-spread function (PSF). However, unresolved binary stars can significantly…

Instrumentation and Methods for Astrophysics · Physics 2017-11-01 T. Kuntzer , F. Courbin

Photonic Lanterns (PLs) are tapered waveguides that gradually transition from a multi-mode fiber geometry to a bundle of single-mode fibers (SMFs). They can efficiently couple multi-mode telescope light into a multi-mode fiber entrance at…

Instrumentation and Methods for Astrophysics · Physics 2024-02-14 Yoo Jung Kim , Michael P. Fitzgerald , Jonathan Lin , Steph Sallum , Yinzi Xin , Nemanja Jovanovic , Sergio Leon-Saval

In principle, diffractive optics, particularly Phase Fresnel Lenses (PFLs), offer the ability to construct large, diffraction-limited, and highly efficient X-ray/$\gamma$-ray telescopes, leading to dramatic improvement in angular resolution…

Off-axis telescopes with unobstructed pupils offer great advantages in terms of emissivity, throughput, and diffractionlimited energy concentration. For most telescope designs, implementation of an off-axis configuration imposes enormous…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 Will Saunders

We present a technique to determine the polarization properties of a telescope through observations of spectral lines that have no intrinsic linear polarization signals. For such spectral lines, any observed linear polarization must be…

Instrumentation and Methods for Astrophysics · Physics 2018-04-05 A. Derks , C. Beck , V. Martinez Pillet

The Point Spread Function (PSF) is a key figure of merit for specifying the angular resolution of optical systems and, as the demand for higher and higher angular resolution increases, the problem of surface finishing must be taken…

Instrumentation and Methods for Astrophysics · Physics 2016-10-04 K. Tayabaly , D. Spiga , G. Sironi , R. Canestrari , M. Lavagna , G. Pareschi

Weak lensing by large-scale structure is an invaluable cosmological tool given that most of the energy density of the concordance cosmology is invisible. Several large ground-based imaging surveys will attempt to measure this effect over…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-18 Eric M. Huff , Christopher M. Hirata , Rachel Mandelbaum , David Schlegel , Uros Seljak , Robert H. Lupton

Unidirectional invisibility of a PT-symmetric optical system is of great interest, but challenging as well since it is infeasible to fulfill it through wide optical frequency ranges in all angular directions. Accordingly we study…

Optics · Physics 2017-01-05 Mustafa Sarisaman

We present a method for speckle holography that is optimised for crowded fields. Its two key features are an iterativ improvement of the instantaneous Point Spread Functions (PSFs) extracted from each speckle frame and the (optional)…

Instrumentation and Methods for Astrophysics · Physics 2015-05-30 R. Schoedel , S. Yelda , A. Ghez , J. H. V. Girard , L. Labadie , R. Rebolo , A. Perez-Garrido , M. R. Morris

Aims. The main goal of this paper is to derive observational constraints on the halo mass fuction (HMF) by performing a tomographic analysis of the magnification bias signal on a sample of background submillimeter galaxies. The results can…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-15 M. M. Cueli , L. Bonavera , J. Gonzalez-Nuevo , D. Crespo , J. M. Casas , A. Lapi

One of the possible approaches to detecting optical counterparts of GRBs requires monitoring large parts of the sky. This idea has gained some instrumental support in recent years, such as with the "Pi of the Sky" project. The broad sky…

Point spread function (PSF) engineering is vital for precisely controlling the focus of light in computational imaging, with applications in neural imaging, fluorescence microscopy, and biophotonics. The PSF is derived from the magnitude of…

Optics · Physics 2025-04-22 Aleksey Valouev

In recent years, a great deal of emphasis has been placed on achieving the diffraction limit with large aperture telescopes. For a well matched focal-plane instrument, the diffraction limit provides the highest possible angular resolution…

Astrophysics · Physics 2009-11-11 J. Bland-Hawthorn , A. Horton

Optical microscopy is an essential tool in biology and medicine. Imaging thin, yet non-flat objects in a single shot (without relying on more sophisticated sectioning setups) remains challenging as the shallow depth of field that comes with…

Image and Video Processing · Electrical Eng. & Systems 2020-10-14 Adrian Shajkofci , Michael Liebling

The Palomar Transient Factory (PTF) is a fully-automated, wide-field survey aimed at a systematic exploration of the optical transient sky. The transient survey is performed using a new 8.1 square degree camera installed on the 48-inch…

Two all-spherical catadioptric optical systems with a Mangin mirror are described. The design A (aperture 500 mm, f/2.0) has flat field of view of 7 deg in diameter; the design B (aperture 1000 mm, f/1.7) has 10-deg flat field. Both designs…

Astrophysics · Physics 2007-10-12 V. Yu. Terebizh
‹ Prev 1 3 4 5 6 7 10 Next ›