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Related papers: Adaptive Aperture Defocused Digital Speckle Photog…

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Optical beams and starlight distorted by atmospheric turbulence can be corrected with adaptive optics systems to enable efficient coupling into single-mode fibers. Deformable mirrors, used to flatten the wavefront in astronomical…

Speckle metrology exploits the high sensitivity of scattered fields to parameters of interest, yet this also leaves measurements vulnerable to unintended perturbations. Here we employ transmission matrix formalism to engineer light fields…

Optics · Physics 2026-04-08 Hal Gee , Morgan Facchin , Graham D. Bruce

Compared with conventional grating-based spectrometers, reconstructive spectrometers based on spectrally engineered filtering have the advantage of miniaturization because of the less demand for dispersive optics and free propagation space.…

Optics · Physics 2023-11-01 Weizhu Xu , Qingbin Fan , Peicheng Lin , Jiarong Wang , Hao Hu , Tao Yue , Xuemei Hu , Ting Xu

Flat optics have been proposed as an attractive approach for the implementation of new imaging and sensing modalities to replace and augment refractive optics. However, chromatic aberrations impose fundamental limitations on diffractive…

Incoherently illuminated or luminescent objects give rise to a low-contrast speckle-like pattern when observed through a thin diffusive medium, as such a medium effectively convolves their shape with a speckle-like point spread function…

We introduce a synthetic aperture imaging framework that takes into consideration directional dependence of the reflectivity that is to be imaged, as well as its frequency dependence. We use an $\ell_1$ minimization approach that is…

Optimization and Control · Mathematics 2016-01-05 Liliana Borcea , Miguel Moscoso , George Papanicolaou , Chrysoula Tsogka

In depth from defocus (DFD), when images are captured with different camera parameters, a relative magnification is induced between them. Image warping is a simpler solution to account for magnification than seemingly more accurate optical…

Computer Vision and Pattern Recognition · Computer Science 2012-11-06 Arnav Bhavsar

We present a method to determine the static aberrations in a nearly diffraction-limited spectrograph introduced, for example, by alignment or manufacturing errors. We consider an instrument with two stages separated by a slit or image…

Instrumentation and Methods for Astrophysics · Physics 2022-06-01 B. Sánchez , A. M. Watson , S. Cuevas

We measure spectral properties of surface thermal fluctuations of liquids, solids, complex fluids and biological matter using light scattering methods. The random thermal fluctuations are delineated from random noise at sub-shot noise…

Soft Condensed Matter · Physics 2015-05-13 Takahisa Mitsui , Kenichiro Aoki

Wide-field survey instruments are used to efficiently observe large regions of the sky. To achieve the necessary field of view, and to provide a higher signal-to-noise ratio for faint sources, many modern instruments are undersampled.…

Encoding of spectral information onto monochrome imaging cameras is of interest for wavelength multiplexing and hyperspectral imaging applications. Here, the complex spatio-spectral response of a disordered material is used to demonstrate…

Optics · Physics 2017-05-09 Rebecca French , Sylvain Gigan , Otto L. Muskens

An increasing number of research topics and applications ask for a precise measurement of the size distribution of small bubbles in a liquid - and hence for reliable and automated image analysis. However, due to the strong mismatch between…

Soft Condensed Matter · Physics 2016-11-24 Thibaut Gaillard , Clément Honorez , Maxime Jumeau , Florence Elias , Wiebke Drenckhan

We propose depth from coupled optical differentiation, a low-computation passive-lighting 3D sensing mechanism. It is based on our discovery that per-pixel object distance can be rigorously determined by a coupled pair of optical…

Computer Vision and Pattern Recognition · Computer Science 2024-09-18 Junjie Luo , Yuxuan Liu , Emma Alexander , Qi Guo

We experimentally demonstrated a spectral imaging scheme with dual compressed sensing. With the dimensions of spectral and spatial information both compressed, the spectral image of a colored object can be obtained with only a single point…

Optics · Physics 2015-02-17 Xue-Feng Liu , Wen-Kai Yu , Xu-Ri Yao , Bin Dai , Long-Zhen Li , Chao Wang , Guang-Jie Zhai

We propose and examine the use of biphoton pairs, such as those created in parametric down conversion or four-wave mixing, to enhance the precision and the resolution of measuring optical displacements by position-sensitive detection. We…

Quantum Physics · Physics 2016-05-04 Kevin Lyons , Shengshi Pang , Paul G. Kwiat , Andrew N. Jordan

Recording and identifying faint objects through atmospheric scattering media by an optical system are fundamentally interesting and technologically important. In this work, we introduce a comprehensive model that incorporates contributions…

Optics · Physics 2024-04-24 Libang Chen , Jun Yang , Lingye Chen , Yuyang Shui , Yikun Liu , Jianying Zhou

Images of a scene observed under a variable illumination or with a variable optical aperture are not identical. Does a privileged representant exist? In which mathematical context? How to obtain it? The authors answer to such questions in…

Computer Vision and Pattern Recognition · Computer Science 2014-12-19 Vasile Patrascu , Vasile Buzuloiu

Hyperspectral imaging is useful for applications ranging from medical diagnostics to agricultural crop monitoring; however, traditional scanning hyperspectral imagers are prohibitively slow and expensive for widespread adoption. Snapshot…

Image and Video Processing · Electrical Eng. & Systems 2020-09-30 Kristina Monakhova , Kyrollos Yanny , Neerja Aggarwal , Laura Waller

A multispeckle technique for efficiently measuring correctly ensemble-averaged intensity autocorrelation functions of scattered light from non-ergodic and/or non-stationary systems is described. The method employs a CCD camera as a…

Soft Condensed Matter · Physics 2009-11-07 Virgile. Viasnoff , Francois Lequeux , D. J. Pine

We introduce and analyze the concept of space-spectrum uncertainty for certain commonly-used designs for spectrally programmable cameras. Our key finding states that, it is impossible to simultaneously capture high-resolution spatial images…

Image and Video Processing · Electrical Eng. & Systems 2021-01-01 Vishwanath Saragadam , Aswin Sankaranarayanan