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Adaptive optics systems are essential on all large telescopes where image quality is important. These are complex systems with many design parameters requiring optimisation before good performance can be achieved. The simulation of adaptive…

Astrophysics · Physics 2007-05-23 Alastair Basden , Timothy Butterley , Richard Myers , Richard Wilson

Aberrations limit optical systems in many situations, for example when imaging in biological tissue. Machine learning offers novel ways to improve imaging under such conditions by learning inverse models of aberrations. Learning requires…

Optics · Physics 2021-04-30 Ivan Vishniakou , Johannes D. Seelig

Instruments for radio astronomical observations have come a long way. While the first telescopes were based on very large dishes and 2-antenna interferometers, current instruments consist of dozens of steerable dishes, whereas future…

Instrumentation and Methods for Astrophysics · Physics 2015-03-13 Stefan J. Wijnholds , Sebastiaan van der Tol , Ronald Nijboer , Alle-Jan van der Veen

The paper proposes a novel calibration approach for the Orthoglide-type mechanisms based on observations of the manipulator leg parallelism during mo-tions between the prespecified test postures. It employs a low-cost measuring system…

Robotics · Computer Science 2007-11-13 Anatoly Pashkevich , Damien Chablat , Philippe Wenger

Camera calibration is a crucial step in photogrammetry and 3D vision applications. This paper introduces a novel camera calibration method using a designed collimator system. Our collimator system provides a reliable and controllable…

Computer Vision and Pattern Recognition · Computer Science 2025-12-19 Shunkun Liang , Banglei Guan , Zhenbao Yu , Dongcai Tan , Pengju Sun , Zibin Liu , Qifeng Yu , Yang Shang

Many underwater applications rely on vision sensors and require proper camera calibration, i.e. knowing the incoming light ray for each pixel in the image. While for the ideal pinhole camera model all viewing rays intersect in a single 3D…

Computer Vision and Pattern Recognition · Computer Science 2025-08-11 Felix Seegräber , Mengkun She , Felix Woelk , Kevin Köser

The availability and performance of laser-based adaptive optics (AO) systems are strongly dependent on the power and quality of the laser beam before being projected to the sky. Frequent and time-consuming alignment procedures are usually…

Instrumentation and Methods for Astrophysics · Physics 2014-05-23 Clémentine Béchet , Andrés Guesalaga , Benoit Neichel , Vincent Fesquet , Héctor González-Núñez , Sebastián Zúñiga , Pedro Escarate , Dani Guzman

Camera calibration is a crucial step in photogrammetry and 3D vision applications. In practical scenarios with a long working distance to cover a wide area, target-based calibration methods become complicated and inflexible due to site…

Computer Vision and Pattern Recognition · Computer Science 2024-10-01 Shunkun Liang , Banglei Guan , Zhenbao Yu , Pengju Sun , Yang Shang

Environment perception is a key component of any autonomous system and is often based on a heterogeneous set of sensors and fusion thereof for which sensor sensor calibration plays fundamental role. It can be divided to intrinsic and…

Robotics · Computer Science 2019-01-01 Juraj Peršić

It is widely believed that adaptive optics only has a role in correcting turbulent wavefronts on large telescopes using very bright reference stars. Unfortunately these are very scarce and many astronomical targets require wavefront…

Instrumentation and Methods for Astrophysics · Physics 2019-11-19 Craig Mackay

As we look to the next generation of adaptive optics systems, now is the time to develop and explore the technologies that will allow us to image rocky Earth-like planets; wavefront control algorithms are not only a crucial component of…

Earth and Planetary Astrophysics · Physics 2023-09-06 J. Fowler , Rico Landman

The reconstruction of a scene via a stereo-camera system is a two-steps process, where at first images from different cameras are matched to identify the set of point-to-point correspondences that then will actually be reconstructed in the…

Computer Vision and Pattern Recognition · Computer Science 2021-01-15 Riccardo Beschi , Xiao Feng , Stefania Melillo , Leonardo Parisi , Lorena Postiglione

We propose a method for automatic calibration of a traffic surveillance camera with wide-angle lenses. Video footage of a few minutes is sufficient for the entire calibration process to take place. This method takes in the height of the…

Computer Vision and Pattern Recognition · Computer Science 2020-01-22 Aman Gajendra Jain , Nicolas Saunier

Camera calibration is an essential first step in setting up 3D Computer Vision systems. Commonly used parametric camera models are limited to a few degrees of freedom and thus often do not optimally fit to complex real lens distortion. In…

Computer Vision and Pattern Recognition · Computer Science 2020-06-24 Thomas Schöps , Viktor Larsson , Marc Pollefeys , Torsten Sattler

Time-of-flight cameras provide depth information, which is complementary to the photometric appearance of the scene in ordinary images. It is desirable to merge the depth and colour information, in order to obtain a coherent scene…

Computer Vision and Pattern Recognition · Computer Science 2020-12-18 Miles Hansard , Georgios Evangelidis , Quentin Pelorson , Radu Horaud

In most optomechanical systems a movable mirror is a part of an optical cavity, and its oscillation modulates either the resonance frequency of the cavity, or its coupling to the environment. There exists the third option -- which we call a…

Quantum Physics · Physics 2019-12-04 Xiang Li , Mikhail Korobko , Yiqiu Ma , Roman Schnabel , Yanbei Chen

Current and future high-contrast imaging instruments require extreme Adaptive Optics (XAO) systems to reach contrasts necessary to directly image exoplanets. Telescope vibrations and the temporal error induced by the latency of the control…

Instrumentation and Methods for Astrophysics · Physics 2020-12-04 Rico Landman , Sebastiaan Y. Haffert , Vikram M. Radhakrishnan , Christoph U. Keller

Typical Structure-from-Motion (SfM) pipelines rely on finding correspondences across images, recovering the projective structure of the observed scene and upgrading it to a metric frame using camera self-calibration constraints. Solving…

Computer Vision and Pattern Recognition · Computer Science 2020-07-07 Rui Gong , Danda Pani Paudel , Ajad Chhatkuli , Luc Van Gool

Reinforcement Learning (RL) presents a new approach for controlling Adaptive Optics (AO) systems for Astronomy. It promises to effectively cope with some aspects often hampering AO performance such as temporal delay or calibration errors.…

Instrumentation and Methods for Astrophysics · Physics 2021-05-19 Jalo Nousiainen , Chang Rajani , Markus Kasper , Tapio Helin

The maintenance of primary mirror segment co-phasing is a critical aspect to the operation of segmented telescopes. However, speckle-based measurements of the phasing of the Keck primary have estimated semi-static surface aberrations of…

Instrumentation and Methods for Astrophysics · Physics 2025-03-05 Benjamin Calvin , Michael Fitzgerald