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Numerical Simulation is an essential part of the design and optimisation of astronomical adaptive optics systems. Simulations of adaptive optics are computationally expensive and the problem scales rapidly with telescope aperture size, as…

Astrophysics · Physics 2009-11-13 A. G. Basden , F. Assemat , T. Butterley , D. Geng , C. D. Saunter , R. W. Wilson

Observations close to the diffraction limit, with high Strehl ratios from Adaptive Optics (AO)-assisted instruments mounted on ground-based telescopes are a reality and will become even more widespread with the next generation instruments…

Instrumentation and Methods for Astrophysics · Physics 2023-10-23 Matteo Simioni , Carmelo Arcidiacono , Andrea Grazian , Marco Gullieuszik , Elisa Portaluri , Benedetta Vulcani , Roland Wagner , Anita Zanella

The forecast on a time scale of 1 or 2 hours is crucial for all kind of new generation facilities (ELTs) instrumentation supported by the adaptive optics that will be mainly operated in Service Mode. In a recent study (Masciadri et al.…

Instrumentation and Methods for Astrophysics · Physics 2023-08-08 Elena Masciadri , Alessio Turchi , Luca Fini

This paper presents a numerical study on a fast marching method based back projection reconstruction algorithm for photoacoustic tomography in heterogeneous media. Transcranial imaging is used here as a case study. To correct for the phase…

Medical Physics · Physics 2015-01-21 Tianren Wang , Yun Jing

Orbital Angular Momentum (OAM)-based communication systems offer high-capacity multiplexing in line-of-sight (LOS) scenarios; yet, their performance is sensitive to nodal misalignment, which disrupts modal orthogonality, hindering the data…

Signal Processing · Electrical Eng. & Systems 2026-01-27 Poorya Mollahosseini , Yasaman Ghasempour

The Multipath effect in Time-of-Flight(ToF) cameras still remains to be a challenging problem that hinders further processing of 3D data information. Based on the evidence from previous literature, we explored the possibility of using…

Computer Vision and Pattern Recognition · Computer Science 2016-01-13 Mojmir Mutny , Rahul Nair , Jens-Malte Gottfried

The Earth's turbulent atmosphere results in speckled and blurred images of astronomical objects when observed by ground based visible and near-infrared telescopes. Adaptive optics (AO) systems are employed to reduce these atmospheric…

Instrumentation and Methods for Astrophysics · Physics 2022-11-30 Daniel M. Levinstein , Saavidra Perera , Quinn M. Konopacky , Alex Madurowicz , Bruce Macintosh , Lisa Poyneer , Richard W. Wilson

The Multi-conjugate Adaptive Optics RelaY (MAORY) is one of the key Adaptive Optics (AO) systems on the European Southern Observatory's Extremely Large Telescope. MAORY aims to achieve a good wavefront correction over a large field of view,…

Instrumentation and Methods for Astrophysics · Physics 2022-02-25 Bernadett Stadler , Ronny Ramlau

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

The free-space optical (FSO) communication links with orbital angular momentum (OAM) multiplexing have been demonstrated that they can largely enhance the systems' capacity without a corresponding increase in spectral bandwidth, but the…

Optics · Physics 2014-01-30 Shengmei Zhao , Bei Wang , Li Zhou , Longyan Gong , Wenwen Cheng , Yubo Sheng , Baoyu Zheng

We propose and demonstrate a method for the adaptive wavefront correction of dynamic multimode fiber beams for the first time. The wavefront of incident beam is reconstructed in real-time based on the complete modal information, which…

Adaptive optics (AO) is a powerful image correction technique with proven benefits for many life-science microscopy methods. However, the complexity of adding a reflective wavefront modulator and a wavefront sensor into already complicated…

Observational tests of ground layer wavefront recovery have been made in open loop using a constellation of four natural guide stars at the 1.55 m Kuiper telescope in Arizona. Such tests explore the effectiveness of wide-field seeing…

Astrophysics · Physics 2011-02-11 Christoph Baranec , Michael Lloyd-Hart , N. Mark Milton

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

Millimeter wave is a promising technology for the next generation of wireless systems. As it is well-known for its high path loss, the systems working in this spectrum tend to exploit the shorter wavelength to equip the transceivers with a…

Information Theory · Computer Science 2018-01-12 Sina Shaham , Matthew Kokshoorn , Zihuai Lin , Ming Ding

The highest scientific return, for adaptive optics (AO) observations, is achieved with a reliable reconstruction of the PSF. This is especially true for MICADO@ELT. In this presentation, we will focus on extending the MICADO PSF…

An important factor which affects performance of solar adaptive optics (AO) systems is the accuracy of tracking an extended object in the wavefront sensor. The accuracy of a centre-ofmass approach to image shift measurement depends on the…

Instrumentation and Methods for Astrophysics · Physics 2015-08-21 M. J. Townson , A. Kellerer , C. D. Saunter

The next generation of extreme adaptive optics (AO) must be calibrated exceptionally well to achieve the desired contrast for ground-based direct imaging exoplanet targets. Current wavefront sensing and control system responses deviate from…

Magnetic resonance fingerprinting (MRF) provides a unique concept for simultaneous and fast acquisition of multiple quantitative MR parameters. Despite acquisition efficiency, adoption of MRF into the clinics is hindered by its dictionary…

Image and Video Processing · Electrical Eng. & Systems 2020-08-11 Fabian Balsiger , Alain Jungo , Olivier Scheidegger , Pierre G. Carlier , Mauricio Reyes , Benjamin Marty

We investigate the focal plane wavefront sensing technique, known as Phase Diversity, at the scientific focal plane of a segmented mirror telescope with an adaptive optics (AO) system. We specifically consider an optical system imaging a…

Instrumentation and Methods for Astrophysics · Physics 2021-05-03 Masen Lamb , Carlos Correia , Suresh Sivanandam , Robin Swanson , Polina Zavyalova