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Related papers: Phasing a deployable sparse telescope

200 papers

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

A sparse modeling approach is proposed for analyzing scanning tunneling microscopy topography data, which contains numerous peaks corresponding to surface atoms. The method, based on the relevance vector machine with $\mathrm{L}_1$…

Data Analysis, Statistics and Probability · Physics 2018-03-13 Masamichi J. Miyama , Koji Hukushima

We present the experimental reconstruction of sub-wavelength features from the far-field intensity of sparse optical objects: sparsity-based sub-wavelength imaging combined with phase-retrieval. As examples, we demonstrate the recovery of…

When a single molecule is detected in a wide-field microscope, the image approximates the point spread function of the system. However, as the distribution of molecules becomes denser and their images begin to coincide, existing solutions…

Optics · Physics 2013-09-02 Anthony Barsic , Ginni Grover , Rafael Piestun

Imaging of scenes using light or other wave phenomena is subject to the diffraction limit. The spatial profile of a wave propagating between a scene and the imaging system is distorted by diffraction resulting in a loss of resolution that…

Image and Video Processing · Electrical Eng. & Systems 2020-07-20 Ji Hyun Nam , Andreas Velten

The fields of view of Extremely Large Telescopes will contain vast numbers of spatial sampling elements (spaxels) as their Adaptive Optics systems approach the diffraction limit over wide fields. Since this will exceed the detection…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 G. J. Murray , J. R. Allington-Smith

For segmented telescopes, achieving fine co-focus adjustment is essential for realizing co-phase adjustment and maintenance, which involves adjusting the millimeter-scale piston between segments to fall within the capture range of the…

Instrumentation and Methods for Astrophysics · Physics 2024-04-12 Kunyan Wang , Yichun Dai , Bin Wang , Xu Tan , Dehua Yang , Zhenyu Jin

We propose a new method for fine-grained few-shot recognition via deep object parsing. In our framework, an object is made up of K distinct parts and for each part, we learn a dictionary of templates, which is shared across all instances…

Computer Vision and Pattern Recognition · Computer Science 2022-10-14 Ruizhao Zhu , Pengkai Zhu , Samarth Mishra , Venkatesh Saligrama

Astrometric detection and mass determination of Earth-mass exoplanets requires sub-microarcsec accuracy, which is theoretically possible with an imaging space telescope using field stars as an astrometric reference. The measurement must…

We have developed a new technique for weak lensing analysis, with which the effect of the point spread function (PSF) on small galaxy images can be corrected for accurately. Rather than relying on weighted second moments of detected images,…

Astrophysics · Physics 2016-08-30 Konrad Kuijken

We present an algorithm to estimate fast and accurate depth maps from light fields via a sparse set of depth edges and gradients. Our proposed approach is based around the idea that true depth edges are more sensitive than texture edges to…

Computer Vision and Pattern Recognition · Computer Science 2021-07-08 Numair Khan , Min H. Kim , James Tompkin

Co-phase and co-focus detection is one of the key technologies for large-aperture segmented mirror telescopes. In this paper, a new edge sensor based on fringes of equal thickness is developed, which can detect each segment's relative…

Instrumentation and Methods for Astrophysics · Physics 2023-06-27 Xi Zhang , Heng Zuo , Yong Zhang , Ye-Ping Li

We present a fast and accurate method for dense depth reconstruction from sparsely sampled light fields obtained using a synchronized camera array. In our method, the source images are over-segmented into non-overlapping compact superpixels…

Image and Video Processing · Electrical Eng. & Systems 2018-12-18 Aleksandra Chuchvara , Attila Barsi , Atanas Gotchev

We have designed and constructed a second-generation version of the Dispersed Fourier Transform Spectrograph, or dFTS. This instrument combines a spectral interferometer with a dispersive spectrograph to provide high-accuracy,…

Instrumentation and Methods for Astrophysics · Physics 2014-11-20 Bradford B. Behr , Arsen R. Hajian , Andrew T. Cenko , Marc Murison , Robert S. McMillan , Robert Hindsley , Jeff Meade

In weak lensing investigations, galaxy shapes are deconvolved for the effects of the point spread function (PSF) using stellar images. In this paper we use physical models of the telescope optics to understand the spatial variation of the…

Astrophysics · Physics 2008-10-02 Mike Jarvis , Paul Schechter , Bhuvnesh Jain

An unbiased method for improving the resolution of astronomical images is presented. The strategy at the core of this method is to establish a linear transformation between the recorded image and an improved image at some desirable…

Astrophysics · Physics 2016-08-30 F. P. Pijpers

Existing unsupervised image alignment methods exhibit limited accuracy and high computational complexity. To address these challenges, we propose a dense cross-scale image alignment model. It takes into account the correlations between…

Computer Vision and Pattern Recognition · Computer Science 2025-11-13 Jinkun You , Jiaxue Li , Jie Zhang , Yicong Zhou

The need of reconstructing discrete-valued sparse signals from few measurements, that is solving an undetermined system of linear equations, appears frequently in science and engineering. Whereas classical compressed sensing algorithms do…

Optimization and Control · Mathematics 2016-09-30 Sandra Keiper , Gitta Kutyniok , Dae Gwan Lee , Götz E. Pfander

We present a technique for measuring the transverse spatial properties of an optical wavefront. Intensity and phase profiles are recovered by analysis of a series of interference patterns produced by the combination of a scanning X-shaped…

Optics · Physics 2015-06-15 David T. Lloyd , Kevin O'Keeffe , Simon M. Hooker

Ptychography has become prominent at synchrotron facilities worldwide for characterizing biological and material specimens' topological structures and properties at the nanometer or atomic scale, due to its lens - less, highly quantitative…

Image and Video Processing · Electrical Eng. & Systems 2025-01-28 Tao Liu , Bingyang Wang , JiangTao Zhao , Maik Kahnt , Fucai Zhang