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Atmospheric tomography, the problem of reconstructing atmospheric turbulence profiles from wavefront sensor measurements, is an integral part of many adaptive optics systems used for enhancing the image quality of ground-based telescopes.…

Numerical Analysis · Mathematics 2025-02-06 Lukas Weissinger , Simon Hubmer , Bernadett Stadler , Ronny Ramlau

We consider the problem of atmospheric tomography, as it appears for example in adaptive optics systems for extremely large telescopes. We derive a frame decomposition, i.e., a decomposition in terms of a frame, of the underlying…

Numerical Analysis · Mathematics 2021-12-06 Simon Hubmer , Ronny Ramlau

Adaptive optics (AO) is a technology in modern ground-based optical telescopes to compensate the wavefront distortions caused by atmospheric turbulence. One method that allows to retrieve information about the atmosphere from telescope data…

Instrumentation and Methods for Astrophysics · Physics 2018-04-04 Tapio Helin , Stefan Kindermann , Jonatan Lehtonen , Ronny Ramlau

Image restoration algorithms for atmospheric turbulence are known to be much more challenging to design than traditional ones such as blur or noise because the distortion caused by the turbulence is an entanglement of spatially varying…

Image and Video Processing · Electrical Eng. & Systems 2022-07-26 Zhiyuan Mao , Ajay Jaiswal , Zhangyang Wang , Stanley H. Chan

Ground based long-range passive imaging systems often suffer from degraded image quality due to a turbulent atmosphere. While methods exist for removing such turbulent distortions, many are limited to static sequences which cannot be…

Image and Video Processing · Electrical Eng. & Systems 2020-09-02 Zhiyuan Mao , Nicholas Chimitt , Stanley Chan

In this paper, we derive explicit reconstruction formulas for two common measurement geometries: a plane and a sphere. The problem is formulated as inverting the forward operator $R^a$, which maps the initial source to the measured wave…

Analysis of PDEs · Mathematics 2025-08-27 Cong Shi

The performance of tomographic adaptive optics systems is intrinsically linked to the vertical profile of optical turbulence. Firstly, a sufficient number of discrete turbulent layers must be reconstructed to model the true continuous…

Instrumentation and Methods for Astrophysics · Physics 2020-04-08 O. J. D. Farley , J. Osborn , T. Morris , T. Fusco , B. Neichel , C. Correia , R. W. Wilson

Seeing-limited resolution in large telescopes working over wide wavelength range depends substantially on the turbulence outer scale and cannot be adequately described by one "seeing" value. We attempt to clarify frequent confusions on this…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 P. Martinez , J. Kolb , A. Tokovinin , M. Sarazin

We consider the problem of thermoacoustic tomography (TAT), in which one needs to reconstruct the initial value of a solution of the wave equation from its value on an observation surface. We show that if some geometric rays for the…

Analysis of PDEs · Mathematics 2009-12-15 Linh V. Nguyen

The influence of atmospheric turbulence on acquired imagery makes image interpretation and scene analysis extremely difficult and reduces the effectiveness of conventional approaches for classifying and tracking objects of interest in the…

Computer Vision and Pattern Recognition · Computer Science 2024-09-24 Paul Hill , Nantheera Anantrasirichai , Alin Achim , David Bull

We describe a method for recovering the irradiance underlying a collection of images corrupted by atmospheric turbulence. Since supervised data is often technically impossible to obtain, assumptions and biases have to be imposed to solve…

Computer Vision and Pattern Recognition · Computer Science 2024-06-25 Dong Lao , Congli Wang , Alex Wong , Stefano Soatto

While Fourier ptychography (FP) offers super-resolution for macroscopic imaging, its real-world application is severely hampered by atmospheric turbulence, a challenge largely unaddressed in existing macroscopic FP research operating under…

Many adaptive optics systems operate by measuring the distortion of the wavefront in one wavelength range and performing the scientific observations in a second, different wavelength range. One common technique is to measure wavefront…

Astrophysics · Physics 2009-11-07 Henry G. Roe

This paper develops a mathematical framework for interpreting observations of solar inertial waves in an idealized setting. Under the assumption of purely toroidal linear waves on the sphere, the stream function of the flow satisfies a…

Analysis of PDEs · Mathematics 2026-04-10 Tram Thi Ngoc Nguyen , Damien Fournier , Laurent Gizon , Thorsten Hohage

Laser guide stars with adaptive optics allow astronomical image correction in the absence of a natural guide star. Single guide star systems with a star created in the earth's sodium layer can be used to correct the wavefront in the near…

Astrophysics · Physics 2009-11-11 S. Rabien , F. Eisenhauer , R. Genzel , R. I. Davies , T. Ott

A novel approach is presented in this paper to improve images which are altered by atmospheric turbulence. Two new algorithms are presented based on two combinations of a blind deconvolution block, an elastic registration block and a…

Computer Vision and Pattern Recognition · Computer Science 2024-11-13 Jerome Gilles , Tristan Dagobert , Carlo De Franchis

We recently developed a new approach to get a stabilized image from a sequence of frames acquired through atmospheric turbulence. The goal of this algorihtm is to remove the geometric distortions due by the atmosphere movements. This method…

Computer Vision and Pattern Recognition · Computer Science 2024-11-06 Yu Mao , Jerome Gilles

Recovering images from optical interferometric observations is one of the major challenges in the field. Unlike the case of observations at radio wavelengths, in the optical the atmospheric turbulence changes the phases on a very short time…

Modern ground-based telescopes rely on a technology called adaptive optics (AO) in order to compensate for the loss of image quality caused by atmospheric turbulence. Next-generation AO systems designed for a wide field of view require a…

Numerical Analysis · Mathematics 2015-11-24 Tapio Helin , Stefan Kindermann , Daniela Saxenhuber

Rescattering electrons offer great potential as probes of molecular properties on ultrafast timescales. The most famous example is molecular tomography, in which high harmonic spectra of oriented molecules are mapped to ``tomographic…

Atomic Physics · Physics 2016-09-28 Zachary B. Walters , Stefano Tonzani , Chris H. Greene
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