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Extended full-waveform inversion (FWI) has shown promising results for accurate estimation of subsurface parameters when the initial models are not sufficiently accurate. Frequency-domain applications have shown that the augmented…

Numerical Analysis · Mathematics 2021-09-16 Ali Gholami , Hossein S. Aghamiry , Stephane Operto

Classically, optical and near-infrared interferometry have relied on closure phase techniques to produce images. Such techniques allow us to achieve modest dynamic ranges. In order to test the feasibility of next generation optical…

Tomography is an imaging technique that works by reconstructing a scene from acquired data in the form of line integrals of the imaging domain. A fundamental underlying assumption in the reconstruction procedure is the precise alignment of…

Numerical Analysis · Mathematics 2018-07-13 Toby Sanders

In preparation of future Multi-Object Spectrographs (MOS) whose one of the major role is to provide an extensive statistical studies of high redshifted galaxies surveyed, the demonstrator Canary has been designed to tackle technical…

Instrumentation and Methods for Astrophysics · Physics 2016-11-23 O. A. Martin , C. M. Correia , E. Gendron , G. Rousset , D. Gratadour , F. Vidal , T. J. Morris , A. G. Basden , R. M. Myers , B. Neichel , T. Fusco

Adaptive Optics at mid-IR wavelengths has long been seen as either not necessary or easy. The impact of atmospheric turbulence on the performance of 8-10 meter class telescopes in the mid-IR is relatively small compared to other performance…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 R. Stuik , L. Jolissaint , S. Kendrew , S. Hippler , B. Brandl , L. Venema

Since its beginnings, diffraction-limited ground-based adaptive optics (AO) imaging has been limited to wavelengths in the near IR ({\lambda} > 1 micron) and longer. Visible AO ({\lambda} < 1 micron) has proven to be difficult because…

Instrumentation and Methods for Astrophysics · Physics 2010-08-03 Derek Kopon , Jared R. Males , Laird M. Close , Victor Gasho

Adaptive optics (AO) have been used to correct wavefronts to achieve diffraction limited point spread functions in a broad range of optical applications, prominently ground-based astronomical telescopes operating in near infra-red. While…

Instrumentation and Methods for Astrophysics · Physics 2018-10-03 Alexandre J. T. S. Mello , Antonin H. Bouchez , Andrew Szentgyorgyi , Marcos A. van Dam , Henrique Lupinari

Vertex-frequency analysis, particularly the windowed graph Fourier transform (WGFT), is a significant challenge in graph signal processing. Tight frame theories is known for its low computational complexity in signal reconstruction, while…

Signal Processing · Electrical Eng. & Systems 2024-12-31 Linbo Shang , Zhichao Zhang

Multifocal plane microscopy (MUM) allows three dimensional objects to be imaged in a single camera frame. Our approach uses dual orthogonal diffraction phase gratings with a quadratic distortion of the lines to apply defocus to the first…

Optics · Physics 2020-03-13 Benjamin Gore , Noah Schwartz , Paul Dalgarno

Limited-angle computed tomography (LACT) reconstruction is an inverse problem with severe ill-posedness arising from missing projection angles, and it is difficult to restore high-precision images without sufficient prior knowledge. In…

Image and Video Processing · Electrical Eng. & Systems 2026-03-06 Hinako Isogai , Naruki Murahashi , Mitsuhiro Nakamura , Megumi Nakao

Wide field-of-view (FOV) optics are widely used in various imaging, display, and sensing applications. While conventional wide FOV optics rely on cascading multiple elements to suppress coma and other aberrations, it has recently been…

Optics · Physics 2021-08-25 Fan Yang , Sensong An , Mikhail Y. Shalaginov , Hualiang Zhang , Juejun Hu , Tian Gu

Conventional Fourier-domain Optical Coherence Tomography (FD-OCT) systems depend on resampling into wavenumber (k) domain to extract the depth profile. This either necessitates additional hardware resources or amplifies the existing…

Optics · Physics 2025-09-24 Maryam Viqar , Erdem Sahin , Elena Stoykova , Violeta Madjarova

Multi-Conjugate Adaptive Optics (MCAO) combines the advantages of standard adaptive optics, which provides high contrast and high spatial resolution, and of wide field ~1' imaging. Up to recently, MCAO for astronomy was limited to…

Astrophysics · Physics 2009-11-13 H. Bouy , J. Kolb , E. Marchetti , E. L. Martin , N. Huelamo , D. Barrado y Navascues

We propose to explore a cascade extreme Adaptive optics (ExAO) approach with a second stage based on a Zernike wavefront sensor (ZWFS) for exoplanet imaging and spectroscopy. Most exoplanet imagers currently use a single-stage ExAO to…

Instrumentation and Methods for Astrophysics · Physics 2023-09-20 Mamadou N'Diaye , Arthur Vigan , Byron Engler , Markus Kasper , Serban Leveratto , Johan Floriot , Michel Marcos , Christophe Bailet , Kjetil Dohlen

The EAGLE instrument for the E-ELT is a multi-IFU spectrograph, that uses a MOAO system for wavefront correction of interesting lines of sight. We present a Monte-Carlo AO simulation package that has been used to model the performace of…

Instrumentation and Methods for Astrophysics · Physics 2018-08-29 Alastair Basden , Timothy Butterley , Richard Myers

The MCAO Assisted Visible Imager and Spectrograph (MAVIS) is a new visible instrument for ESO Very Large Telescope (VLT). Its Adaptive Optics Module (AOM) must provide extreme adaptive optics correction level at low galactic latitude and…

Instrumentation and Methods for Astrophysics · Physics 2022-09-01 Guido Agapito , Daniele Vassallo , Cédric Plantet , Jesse Cranney , Hao Zhang , Valentina Viotto , Enrico Pinna , Francois Rigaut

(abridged) Extreme adaptive optics (XAO) encounters severe difficulties to cope with the high speed (>1kHz), high accuracy and high order requirements for future extremely large telescopes. An innovative high order adaptive optics system…

Instrumentation and Methods for Astrophysics · Physics 2015-09-29 Christian Delacroix , Maud Langlois , Magali Loupias , Eric Thiébaut , Louisa Adjali , Jonathan Leger , Michel Tallon

Understanding, optimizing, and controlling the optical absorption process, exciton gemination, and electron-hole separation and conduction in low dimensional systems is a fundamental problem in materials science. However, robust and…

Mesoscale and Nanoscale Physics · Physics 2020-08-26 Keenan Lyon , María Rosa Preciado-Rivas , Duncan John Mowbray , Vito Despoja

Optical imperfections, misalignments, aberrations, and even dust can significantly limit sensitivity in high-contrast imaging systems such as coronagraphs. An upstream deformable mirror (DM) in the pupil can be used to correct or compensate…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 Johanan L. Codona , Matthew Kenworthy

Photoacoustic computed tomography (PACT), also known as optoacoustic tomography, is an emerging imaging modality that has great potential for a wide range of biomedical imaging applications. In this Note, we derive a hybrid reconstruction…

Analysis of PDEs · Mathematics 2015-06-11 Kun Wang , Mark A. Anastasio
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