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Recent advances in optical metasurfaces enable control of the wavefront, polarization and dispersion of optical waves beyond the capabilities of conventional diffractive optics. An optical design space that is poised to highly benefit from…

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

Hyperspectral image segmentation is crucial for many fields such as agriculture, remote sensing, biomedical imaging, battlefield sensing and astronomy. However, the challenge of hyper and multi spectral imaging is its large data footprint.…

Computer Vision and Pattern Recognition · Computer Science 2024-06-07 Jackson Arnold , Sophia Rossi , Chloe Petrosino , Ethan Mitchell , Sanjeev J. Koppal

The measurement of the wavelength of light using speckle is a promising tool for the realization of compact and precise wavemeters and spectrometers. However, the resolution of these devices is limited by strong correlations between the…

Optics · Physics 2019-09-04 Graham D. Bruce , Laura O'Donnell , Mingzhou Chen , Kishan Dholakia

Accurately measuring the geometry and spatially-varying reflectance of real-world objects is a complex task due to their intricate shapes formed by concave features, hollow engravings and diverse surfaces, resulting in inter-reflection and…

Computer Vision and Pattern Recognition · Computer Science 2024-12-16 Jing Yang , Pratusha Bhuvana Prasad , Qing Zhang , Yajie Zhao

Speckle is a multiplicative noise which affects all coherent imaging modalities including Synthetic Aperture Radar (SAR) images. The presence of speckle degrades the image quality and adversely affects the performance of SAR image…

Image and Video Processing · Electrical Eng. & Systems 2023-06-21 Malsha V. Perera , Nithin Gopalakrishnan Nair , Wele Gedara Chaminda Bandara , Vishal M. Patel

Specular reflections pose a significant challenge for object segmentation, as their sharp intensity transitions often mislead both conventional algorithms and deep learning based methods. However, as the specular reflection must lie on the…

Image and Video Processing · Electrical Eng. & Systems 2026-02-26 Katja Kossira , Yunxuan Zhu , Jürgen Seiler , André Kaup

Light rays incident on a transparent object of uniform refractive index undergo deflections, which uniquely characterize the surface geometry of the object. Associated with each point on the surface is a deflection map (or spectrum) which…

Computer Vision and Pattern Recognition · Computer Science 2015-07-15 Prasad Sudhakar , Laurent Jacques , Xavier Dubois , Philippe Antoine , Luc Joannes

Spectroscopic photoemission microscopy is a well-established method to investigate the electronic structure of surfaces. In modern photoemission microscopes the electron optics allows imaging of the image plane, momentum plane, or…

To effectively apply passive speckle reduction methods, it is essential to use an illumination system that maximally exploits the non-ideal temporal coherence and angular diversity (spatial coherence reduction) of laser light. This study…

Optics · Physics 2025-04-28 A. Lapchuk , O. Prygun , D. Manko , I. Gorbov , Y. Morozov

Adaptive optics (AO) offers an opportunity to stabilize an image and maximize the spatial resolution achievable by ground based telescopes by removing the distortions due to the atmosphere. Typically, the deformable mirror in an AO system…

Instrumentation and Methods for Astrophysics · Physics 2021-07-30 J. Fowler , Rachel Bowens-Rubin , Philip M. Hinz

Whether is ground-based or space-based, any optical instrument suffers from some amount of optical geometric distortion. Recently, the diffraction-limited image quality afforded by space-based telescopes and by Adaptive Optics (AO)…

Instrumentation and Methods for Astrophysics · Physics 2017-11-29 A. Bernard , B. Neichel , L. M. Mugnier , T. Fusco

This paper focuses on improving object detection performance by addressing the issue of image distortions, commonly encountered in uncontrolled acquisition environments. High-level computer vision tasks such as object detection,…

Computer Vision and Pattern Recognition · Computer Science 2024-04-15 Vamshi Krishna Kancharla , Neelam sinha

This thesis proposes spatio-spectral techniques for hyperspectral image analysis. Adaptive spatio-spectral support and variable exposure hyperspectral imaging is demonstrated to improve spectral reflectance recovery from hyperspectral…

Computer Vision and Pattern Recognition · Computer Science 2014-07-30 Zohaib Khan

Image registration has traditionally been done using two distinct approaches: learning based methods, relying on robust deep neural networks, and optimization-based methods, applying complex mathematical transformations to warp images…

Computer Vision and Pattern Recognition · Computer Science 2024-01-22 Gabriel De Araujo , Shanlin Sun , Xiaohui Xie

This study explores the use of photometric techniques (shape-from-shading and uncalibrated photometric stereo) for upsampling the low-resolution depth map from an RGB-D sensor to the higher resolution of the companion RGB image. A…

Computer Vision and Pattern Recognition · Computer Science 2019-06-26 Bjoern Haefner , Songyou Peng , Alok Verma , Yvain Quéau , Daniel Cremers

Most commercially available Light Detection and Ranging (LiDAR)s measure the distances along a 2D section of the environment by sequentially sampling the free range along directions centered at the sensor's origin. When the sensor moves…

Robotics · Computer Science 2023-10-17 Omar Salem , Emanuele Giacomini , Leonardo Brizi , Luca Di Giammarino , Giorgio Grisetti

In astronomy and microscopy, distortions in the wavefront affect the dynamic range of a high contrast imaging system. These aberrations are either imposed by a turbulent medium such as the atmosphere, by static or thermal aberrations in the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Benjamin Pope , Nick Cvetojevic , Anthony Cheetham , Frantz Martinache , Barnaby Norris , Peter Tuthill

In order to increase the corrected field of view of an adaptive optics (AO) system, several deformable mirrors (DM) have to be placed in the conjugate planes of the dominant turbulent layers (multi-conjugate adaptive optics, MCAO [Beckers…

Astrophysics · Physics 2022-04-20 T. Berkefeld , A. Glindemann , S. Hippler

We analyze the far field resolution of apertures which are illuminated by a point dipole located at subwavelength distances. It is well known that radiation emitted by a localized source can be considered a combination of travelling and…

Optics · Physics 2024-03-25 Aziz Kolkiran , G. S. Agarwal
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