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Wave-front sensing from focal plane multiple images is a promising technique for high-contrast imaging systems. However, the wave-front error of an optics system can be properly reconstructed only when it is very small. This paper presents…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 Jiangpei Dou , Deqing Ren , Yongtian Zhu

Wavefront sensing with a thin diffuser has emerged as a potential low-cost alternative to a lenslet array for aberrometry. Diffuser wavefront sensors (DWS) have previously relied on tracking speckle displacement and consequently require…

Optics · Physics 2019-01-01 Gregory N. McKay , Faisal Mahmood , Nicholas J. Durr

The Habitable Worlds Observatory requires active speckle suppression to directly image Earth-like exoplanets. Focal plane wavefront sensing and control allows us to detect, and subsequently remove, time-varying speckles through measurements…

Instrumentation and Methods for Astrophysics · Physics 2025-09-05 Joshua Liberman , Sebastiaan Y. Haffert , Jared R. Males , Kevin Derby , Ewan S. Douglas

We present a quantitative study of coherent array imaging of remote sources in randomly perturbed waveguides with bounded cross-section. We study how long range cumulative scattering by perturbations of the boundary and the medium impedes…

Numerical Analysis · Mathematics 2013-06-10 Liliana Borcea , Josselin Garnier , Chrysoula Tsogka

Continuous wavefront sensing benefits space observatories in on-orbit optical performance maintenance. To measure the phase of a wavefront, phase retrieval is an attractive technique as it uses multiple point spread function (PSF) images…

Instrumentation and Methods for Astrophysics · Physics 2024-09-17 Hyukmo Kang , Kyle Van Gorkom , Meghdoot Biswas , Daewook Kim , Ewan S. Douglas

Early detection of breast cancer through screening mammography yields a 20-35% increase in survival rate; however, there are not enough radiologists to serve the growing population of women seeking screening mammography. Although commercial…

Computer Vision and Pattern Recognition · Computer Science 2020-01-24 Stefano Pedemonte , Brent Mombourquette , Alexis Goh , Trevor Tsue , Aaron Long , Sadanand Singh , Thomas Paul Matthews , Meet Shah , Jason Su

Detecting breast lesion in videos is crucial for computer-aided diagnosis. Existing video-based breast lesion detection approaches typically perform temporal feature aggregation of deep backbone features based on the self-attention…

Computer Vision and Pattern Recognition · Computer Science 2023-09-12 Chao Qin , Jiale Cao , Huazhu Fu , Rao Muhammad Anwer , Fahad Shahbaz Khan

Local amplitude aberrations caused by scintillation can impact the reconstruction process of a wavefront sensor (WFS) by inducing a spatially non-uniform intensity at the pupil plane. This effect is especially relevant for the commonly-used…

Instrumentation and Methods for Astrophysics · Physics 2024-07-23 Stanimir Letchev , Justin R. Crepp , Caleb G. Abbott , Ryan Hersey , Matthew Engstrom , Nicholas Baggett

An undersampled point spread function may interact with the microstructure of a solid-state detector such that the total flux detected can depend sensitively on where the PSF center falls within a pixel. Such intra-pixel sensitivity…

Astrophysics · Physics 2009-10-31 Tod R. Lauer

Real-time seeing estimation at the focus of a telescope is nowadays strongly emphasized as this knowledge virtually drives the dimensioning of adaptive optics systems and instrument operational aspects. In this context we study the interest…

Instrumentation and Methods for Astrophysics · Physics 2015-06-03 P. Martinez , J. Kolb , M. Sarazin , J. Navarrete

Precise centroid estimation plays a critical role in accurate astrometry using telescope images. Conventional centroid estimation fits a template point spread function (PSF) to the image data. Because the PSF is typically not known to high…

Instrumentation and Methods for Astrophysics · Physics 2015-05-27 Chengxing Zhai , Mike Shao , Renaud Goullioud , Bijan Nemati

We investigate methods to calibrate the non-common path aberrations at an adaptive optics system having a wavefront-correcting device working at an extremely high resolution (larger than 150x150). We use focal-plane images collected…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Visa Korkiakoski , Christoph U. Keller , Niek Doelman , Matthew Kenworthy , Gilles Otten , Michel Verhaegen

This paper provides a framework for the incorporation of the wavefront sensor measurements in the context of observing modes in which the science camera takes millisecond exposures. In this formulation, the wavefront sensor measurements…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Richard A. Frazin

In an effort to transcend the limitations of differential imaging of exoplanets in the era of extremely large telescopes (ELTs), the first paper in this series established a rigorous, fully polarimetric framework for determining the science…

Instrumentation and Methods for Astrophysics · Physics 2016-02-18 Richard A. Frazin

Due to the energy-dependent nature of the attenuation coefficient and the polychromaticity of the X-ray source, beam hardening effect occurs when X-ray photons penetrate through an object, causing a nonlinear projection data. When a linear…

Medical Physics · Physics 2018-12-07 Wei Zhao , Dengwang Li , Kai Niu , Wenjian Qin , Hao Peng , Tianye Niu

Multi-core fiber-bundle endoscopes provide a minimally-invasive solution for deep tissue imaging and opto-genetic stimulation, at depths beyond the reach of conventional microscopes. Recently, wavefront-shaping has enabled lensless…

Optics · Physics 2018-11-14 Uri Weiss , Ori Katz

Continuous wavefront sensing on future space telescopes allows relaxation of stability requirements while still allowing on-orbit diffraction-limited optical performance. We consider the suitability of phase retrieval to continuously…

Instrumentation and Methods for Astrophysics · Physics 2023-09-14 Hyukmo Kang , Kyle Van Gorkom , Jess Johnson , Ole Singlestad , Aaron Goldtooth , Daewook Kim , Ewan S. Douglas

The use of Wavefront Sensors (WFS) is nowadays fundamental in the field of instrumental optics. This paper discusses the principle of an original and recently proposed new class of WFS. Their principle consists in evaluating the slopes of…

Optics · Physics 2011-05-23 Francois Henault

New multi-core imaging fibre bundles -- hexabundles -- being developed at the University of Sydney will provide simultaneous integral field spectroscopy for hundreds of celestial sources across a wide angular field. These are a natural…

Instrumentation and Methods for Astrophysics · Physics 2015-05-27 J. J. Bryant , J. W. O'Byrne , J. Bland-Hawthorn , S. G. Leon-Saval

The use of wide-field multi-object fiber-input spectrographs for large redshift surveys introduces the possibility of variations in the observed signal-to-noise ratio across the survey area due to errors in positioning the fibers with…

Astrophysics · Physics 2011-12-16 Peter R. Newman
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