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In absence of a lens to form an image, incoherent or partially coherent light scattering off an obstructive or reflective object forms a broad intensity distribution in the far field with only feeble spatial features. We show here that…

The complete characterization of spatial coherence is difficult because the mutual coherence function is a complex-valued function of four independent variables. This difficulty limits the ability of controlling and optimizing spatial…

The coherence holography offers an unconventional way to reconstruct the hologram where an incoherent light illumination is used for reconstruction purposes, and object encoded into the hologram is reconstructed as the distribution of the…

We propose and demonstrate an interferometric scheme for measuring the two-dimensional two-point cross-spectral density function in a two-shot manner. Our scheme comprises a Michelson interferometer with a converging lens in one of the arms…

Instrumentation and Detectors · Physics 2018-08-01 Abhinandan Bhattacharjee , Shaurya Aarav , Anand K. Jha

We present spatial coherence measurements of partially coherent light in the far-field of incoherent sources with an experimental setup based on the Thompson-Wolf and Partanen-Turunen-Tervo experiments, to be performed in the context of a…

Instrumentation and Detectors · Physics 2021-05-05 Tiago E. C. Magalhães , José M. Rebordão , Alexandre Cabral

The degree of optical spatial coherence -a fundamental property of light that describes the mutual correlations between fluctuating electromagnetic fields- has proven challenging to control at the micrometer scale. Here we employ surface…

Optics · Physics 2016-12-30 Dongfang Li , Domenico Pacifici

When used with coherent light, optical imaging systems, even diffraction-limited, are inherently unable to reproduce both the amplitude and the phase of a two-dimensional field distribution because their impulse response function varies…

Optics · Physics 2009-11-13 E. Brainis , C. Muldoon , L. Brandt , A. Kuhn

Coherent backscattering is a coherence effect in the propagation of waves through disordered media involving two or more scattering events. Here, we report on the observation of coherent backscattering from individual atoms and their mirror…

Recent advances in optical imaging and communication increasingly involve high-dimensional, partially coherent light, creating a growing need for scalable tools to measure and manipulate coherence. Here, we demonstrate the automatic…

Non-line-of-sight (NLOS) imaging relies on collecting light that is rendered incoherent from the multiple scattering events and is then post-processed to provide an estimate of the hidden scene. Here we employ coherent phase control of the…

Optics · Physics 2019-12-25 Ilya Starshynov , Omair Ghafur , James Fitches , Daniele Faccio

We present the first calculation of coherent backscattering with inelastic scattering by saturated atoms. We consider the scattering of a quasi-monochromatic laser pulse by two distant atoms in free space. By restricting ourselves to…

Quantum Physics · Physics 2009-11-10 T. Wellens , B. Gremaud , D. Delande , C. Miniatura

We show a monotonic relationship between performances of various computer vision tasks versus degrees of coherence of illumination. We simulate partially coherent illumination using computational methods, propagate the lightwave to form…

Computer Vision and Pattern Recognition · Computer Science 2024-01-08 Zichen Xie , Ken Xingze Wang

In this paper, we show how the combined use of low coherence interferometry, balanced detection and data processing comparable to that used in Fourier transform spectrometry allows us to characterize with ultimate resolutions (sub-ppm in…

Optics · Physics 2023-05-24 Michel Lequime , Imran Khan , Myriam Zerrad , Claude Amra

Lensless microscopy with coherent or partially coherent light sources is a well known imaging technique, commonly referred as digital in-line holographic microscopy. In the established methods, both the spatial and temporal coherence of…

Optics · Physics 2020-11-04 Sanjeev Kumar , Manjunatha Mahadevappa , Pranab Kumar Dutta

Coherent diffractive imaging is a technique that recovers the sample image by numerically inverting its diffraction pattern. We propose a generalization of this method for the inversion of multi-wavelength data. Using this approach, we show…

Optics · Physics 2020-05-08 Erik Malm , Edwin Fohtung , Anders Mikkelsen

We study coherent backscattering of a quasi-monochromatic laser by a dilute gas of cold two-level atoms. We consider the perturbative regime of weak intensities, where nonlinear effects arise from {\em inelastic} two-photon scattering…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 T. Wellens , B. Gremaud , D. Delande , C. Miniatura

I propose a superoscillation measurement method for subdiffraction incoherent optical sources, with potential applications in astronomy, remote sensing, fluorescence microscopy, and spectroscopy. The proposal, based on coherent optical…

Quantum Physics · Physics 2022-10-10 Mankei Tsang

We consider the non-line-of-sight (NLOS) imaging of an object using the light reflected off a diffusive wall. The wall scatters incident light such that a lens is no longer useful to form an image. Instead, we exploit the 4D spatial…

Computer Vision and Pattern Recognition · Computer Science 2022-12-06 Andre Beckus , Alexandru Tamasan , George K. Atia

Object-motion-based speckle correlation can recover hidden objects from any inhomogeneous medium, which takes advantage of the inherent connection that the cross-correlation between speckle patterns can reflect the autocorrelation of…

Optics · Physics 2023-12-01 Zhao Wang , Rui Ma , Mingzhu She , Anda Shi , Weili Zhang

Spatial coherence plays an important role in several real-world applications ranging from imaging to communication. As a result, its accurate characterization and measurement are extremely crucial for its optimal application. However,…

Optics · Physics 2024-03-04 Pranay Mohta , Abhinandan Bhattacharjee , Anand K. Jha
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