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In coherent X-ray diffraction microscopy the diffraction pattern generated by a sample illuminated with coherent x-rays is recorded, and a computer algorithm recovers the unmeasured phases to synthesize an image. By avoiding the use of a…

Generally, wave field reconstructions obtained by phase-retrieval algorithms are noisy, blurred and corrupted by various artifacts such as irregular waves, spots, etc. These disturbances, arising due to many factors such as non-idealities…

Optics · Physics 2012-07-24 Artem Migukin , Mostafa Agour , Vladimir Katkovnik

Free-space optical communication (FSOC) systems offer high-bandwidth and secure communication with minimal capital costs. Adaptive optics (AO) are typically added to these systems to decrease atmospheric channel losses; however, the…

Path-length diversity methods may be used for adaptive optics (AO) systems to retrieve phase and amplitude information by measuring intensity across multiple planes. Observations that rely on free-space propagation, such as the nonlinear…

The wavefront measurement of a light beam is a complex task, which often requires a series of spatially resolved intensity measurements. For instance, a detector array may be used to measure the local phase gradient in the transverse plane…

In this manuscript we demonstrate a method to reconstruct the wavefront of focused beams from a measured diffraction pattern behind a diffracting mask in real-time. The phase problem is solved by means of a neural network, which is trained…

Image and Video Processing · Electrical Eng. & Systems 2021-04-07 Jonathon White , Sici Wang , Wilhelm Eschen , Jan Rothhardt

Light-field cameras play a vital role for rich 3-D information retrieval in narrow range depth sensing applications. The key obstacle in composing light-fields from exposures taken by a plenoptic camera is to computationally calibrate,…

Image and Video Processing · Electrical Eng. & Systems 2021-07-27 Christopher Hahne , Amar Aggoun

The Zernike wavefront sensor (ZWFS) stands out as one of the most sensitive optical systems for measuring the phase of an incoming wavefront, reaching photon efficiencies close to the fundamental limit. This quality, combined with the fact…

In this paper, we address the problem of reflection removal and deblurring from a single image captured by a plenoptic camera. We develop a two-stage approach to recover the scene depth and high resolution textures of the reflected and…

Computer Vision and Pattern Recognition · Computer Science 2017-08-24 Paramanand Chandramouli , Mehdi Noroozi , Paolo Favaro

State-of-the-art adaptive optics (AO) systems perform non-linear Fourier-type wavefront sensing for real-time corrections of dynamic wavefront aberrations. This general class of sensors uses a filtering mask in the focal plane that converts…

Instrumentation and Methods for Astrophysics · Physics 2025-06-24 Victoria Laidlaw

Shack Hartmann wavefront sensor is a two dimensional array of lenslets which is used to detect the incoming phase distorted wavefront through local tilt measurements made by recording the spot pattern near the focal plane. Wavefront…

Instrumentation and Methods for Astrophysics · Physics 2011-08-16 Akondi Vyas , M B Roopashree , B Raghavendra Prasad

A novel phase retrieval algorithm for broadband hyperspectral phase imaging from noisy intensity observations is proposed. It utilizes advantages of the Fourier Transform spectroscopy in the self-referencing optical setup and provides,…

Image and Video Processing · Electrical Eng. & Systems 2020-06-03 Igor Shevkunov , Vladimir Katkovnik , Karen Egiazarian

An adaptive optics system with a single deformable mirror is being implemented on the THEMIS 90cm solar telescope. This system is designed to operate in the visible and is required to be as robust as possible in order to deliver the best…

Instrumentation and Methods for Astrophysics · Physics 2021-01-11 Michel Tallon , Éric Thiébaut , Maud Langlois , Bernard Gelly , Richard Douet , Clémentine Béchet , Loïc Denis , Gil Moretto

Context. The diffusion of adaptive optics systems in astronomical instrumentation for large ground-based telescopes is rapidly increasing and the pyramid wavefront sensor is replacing the Shack-Hartmann as the standard solution for single…

Instrumentation and Methods for Astrophysics · Physics 2023-09-27 Guido Agapito , Enrico Pinna , Simone Esposito , Cedric Taïssir Heritier , Sylvain Oberti

Phase retrieval in inline holography is a fundamental yet ill-posed inverse problem due to the nonlinear coupling between amplitude and phase in coherent imaging. We present a novel off-the-shelf solution that leverages a diffusion model…

Optics · Physics 2025-11-12 Jeongsol Kim , Chanseok Lee , Jongin You , Jong Chul Ye , Mooseok Jang

For a HOM interferometer with two independent incident pulses, the interference pattern can be affected by adding a dispersion medium on one of the incident directions, but there hasn't been a method to reconstruct the phase constant of the…

Quantum Physics · Physics 2023-10-17 Yuhang Lei , Wen Zhao , Liang cui , Xiaoyin Li

While adaptive optical systems are able to remove moderate wavefront distortions in scintillated optical beams, phase singularities that appear in strongly scintillated beams can severely degrade the performance of such an adaptive optical…

Optics · Physics 2009-11-13 Mingzhou Chen , Filippus S. Roux , Jan C. Olivier

In astronomy or biological imaging, refractive index inhomogeneities of e.g. atmosphere or tissues induce optical aberrations which degrade the desired information hidden behind the medium. A standard approach consists in measuring these…

Optics · Physics 2023-06-01 Tengfei Wu , Marc Guillon , Gilles Tessier , Pascal Berto

A phase retrieval technique using a spatial light modulator (SLM) and a phase diffuser for a fast reconstruction of smooth wave fronts is demonstrated experimentally. Diffuse illumination of a smooth test object with the aid of a phase…

Optics · Physics 2015-06-11 Mostafa Agour , Percival F. Almoro , Claas Falldorf

We discuss the use of parametric phase-diverse phase retrieval as an in-situ high-fidelity wavefront measurement method to characterize and optimize the transmitted wavefront of a high-contrast coronagraphic instrument. We apply our method…

Instrumentation and Methods for Astrophysics · Physics 2019-03-06 Gregory R. Brady , Christopher Moriarty , Peter Petrone , Iva Laginja , Keira Brooks , Tom Comeau , Lucie Leboulleux , Remi Soummer