Computational ghost imaging
TL;DR: In this article, the authors describe a computational ghost-imaging arrangement that uses only a single-pixel detector, which affords background-free imagery in the narrow-band limit and a three-dimensional sectioning capability.
Abstract: Ghost-imaging experiments correlate the outputs from two photodetectors: a high spatial-resolution (scanning pinhole or charge-coupled-device camera) detector that measures a field which has not interacted with the object to be imaged and a bucket (single-pixel) detector that collects a field that has interacted with the object. We describe a computational ghost-imaging arrangement that uses only a single-pixel detector. This configuration affords background-free imagery in the narrow-band limit and a three-dimensional sectioning capability. It clearly indicates the classical nature of ghost-image formation.
Citations
More filters
TL;DR: In this paper, an advanced image reconstruction algorithm for pseudothermal ghost imaging, based on compressed sensing, is presented. But the algorithm is limited to pseudothermal images and cannot be applied to images taken from other pseudothermal imaging experiments.
Abstract: We describe an advanced image reconstruction algorithm for pseudothermal ghost imaging, reducing the number of measurements required for image recovery by an order of magnitude. The algorithm is based on compressed sensing, a technique that enables the reconstruction of an N-pixel image from much less than N measurements. We demonstrate the algorithm using experimental data from a pseudothermal ghost-imaging setup. The algorithm can be applied to data taken from past pseudothermal ghost-imaging experiments, improving the reconstruction’s quality.
793 citations
TL;DR: A computational imaging method is used to reconstruct a three-dimensional scene, without the need for lenses, and this simplified approach to 3D imaging can readily be extended to nonvisible wavebands.
Abstract: Computational imaging enables retrieval of the spatial information of an object with the use of single-pixel detectors. By projecting a series of known random patterns and measuring the backscattered intensity, it is possible to reconstruct a two-dimensional (2D) image. We used several single-pixel detectors in different locations to capture the 3D form of an object. From each detector we derived a 2D image that appeared to be illuminated from a different direction, even though only a single digital projector was used for illumination. From the shading of the images, the surface gradients could be derived and the 3D object reconstructed. We compare our result to that obtained from a stereophotogrammetric system using multiple cameras. Our simplified approach to 3D imaging can readily be extended to nonvisible wavebands.
691 citations
University of Queensland1, University of the Witwatersrand2, University of Bristol3, University of East Anglia4, University of Arizona5, University of Münster6, Max Planck Society7, University of Ottawa8, Istituto Nazionale di Fisica Nucleare9, University of Glasgow10, Innsbruck Medical University11, State University of New York System12, The Institute of Optics13, Polytechnic University of Catalonia14, University of Victoria15, University of Southern California16, University of Oregon17, Purdue University18
TL;DR: In this paper, the key fields within structured light from the perspective of experts in those areas, providing insight into the current state and the challenges their respective fields face, as well as the exciting prospects for the future that are yet to be realized.
Abstract: Structured light refers to the generation and application of custom light fields. As the tools and technology to create and detect structured light have evolved, steadily the applications have begun to emerge. This roadmap touches on the key fields within structured light from the perspective of experts in those areas, providing insight into the current state and the challenges their respective fields face. Collectively the roadmap outlines the venerable nature of structured light research and the exciting prospects for the future that are yet to be realized.
639 citations
20 Aug 2019
TL;DR: This paper relates the deep-learning-inspired solutions to the original computational imaging formulation and use the relationship to derive design insights, principles, and caveats of more general applicability, and explores how the machine learning process is aided by the physics of imaging when ill posedness and uncertainties become particularly severe.
Abstract: Since their inception in the 1930–1960s, the research disciplines of computational imaging and machine learning have followed parallel tracks and, during the last two decades, experienced explosive growth drawing on similar progress in mathematical optimization and computing hardware. While these developments have always been to the benefit of image interpretation and machine vision, only recently has it become evident that machine learning architectures, and deep neural networks in particular, can be effective for computational image formation, aside from interpretation. The deep learning approach has proven to be especially attractive when the measurement is noisy and the measurement operator ill posed or uncertain. Examples reviewed here are: super-resolution; lensless retrieval of phase and complex amplitude from intensity; photon-limited scenes, including ghost imaging; and imaging through scatter. In this paper, we cast these works in a common framework. We relate the deep-learning-inspired solutions to the original computational imaging formulation and use the relationship to derive design insights, principles, and caveats of more general applicability. We also explore how the machine learning process is aided by the physics of imaging when ill posedness and uncertainties become particularly severe. It is hoped that the present unifying exposition will stimulate further progress in this promising field of research.
473 citations
TL;DR: A single-pixel imaging technique that can achieve high-quality images by acquiring their Fourier spectrum by using phase-shifting sinusoid structured illumination for the spectrum acquisition and applying inverse Fourier transform to the obtained spectrum yields the desired image.
Abstract: Single-pixel imaging can capture a scene without a direct line of sight to the object but high-quality imaging has proven challenging. Here, by acquiring their Fourier spectrum, Zhang et al. demonstrate indirect, high-quality single-pixel imaging in the presence of noisy environmental illumination.
468 citations
References
More filters
TL;DR: In this article, a two-photon optical imaging experiment was performed based on the quantum nature of the signal and idler photon pairs produced in spontaneous parametric down-conversion, where an aperture placed in front of a fixed detector is illuminated by the signal beam through a convex lens.
Abstract: A two-photon optical imaging experiment was performed based on the quantum nature of the signal and idler photon pairs produced in spontaneous parametric down-conversion. An aperture placed in front of a fixed detector is illuminated by the signal beam through a convex lens. A sharp magnified image of the aperture is found in the coincidence counting rate when a mobile detector is scanned in the transverse plane of the idler beam at a specific distance in relation to the lens.
1,651 citations
TL;DR: In this paper, a scheme for coherent imaging that exploits the classical correlation of two beams obtained by splitting incoherent thermal radiation is considered, and a precise formal analogy is pointed out.
Abstract: We consider a scheme for coherent imaging that exploits the classical correlation of two beams obtained by splitting incoherent thermal radiation. This case is analyzed in parallel with the configuration based on two entangled beams produced by parametric down-conversion, and a precise formal analogy is pointed out. This analogy opens the possibility of using classical beams from thermal radiation for ghost imaging schemes in the same way as entangled beams.
734 citations
TL;DR: The product of spatial resolutions of the ghost image and ghost diffraction experiments is shown to overcome a limit which seemed to be achievable only with entangled photons.
Abstract: High-resolution ghost image and ghost diffraction experiments are performed by using a single classical source of pseudothermal speckle light divided by a beam splitter. Passing from the image to the diffraction result solely relies on changing the optical setup in the reference arm, while leaving the object arm untouched. The product of spatial resolutions of the ghost image and ghost diffraction experiments is shown to overcome a limit which seemed to be achievable only with entangled photons.
648 citations
TL;DR: The first experimental demonstration of thermal "ghost" imaging is reported, where a two-photon Gaussian thin lens equation is observed and differences and similarities to entangled " ghost" imaging are discussed.
Abstract: We report the first experimental demonstration of two-photon imaging with a pseudothermal source. Similarly to the case of entangled states, a two-photon Gaussian thin lens equation is observed, indicating EPR type correlation in position. We introduce the concepts of two-photon coherent and two-photon incoherent imaging. The differences between the entangled and the thermal cases are explained in terms of these concepts.
632 citations
TL;DR: In this paper, the authors analytically show that it is possible to perform coherent imaging by using the classical correlation of two beams obtained by splitting incoherent thermal radiation, and a formal analogy is demonstrated between two such correlated beams and two entangled beams produced by parametric down-conversion.
Abstract: We analytically show that it is possible to perform coherent imaging by using the classical correlation of two beams obtained by splitting incoherent thermal radiation. A formal analogy is demonstrated between two such classically correlated beams and two entangled beams produced by parametric down-conversion. Because of this analogy, the classical beams can mimic qualitatively all the imaging properties of the entangled beams, even in ways which up to now were not believed possible. A key feature is that these classical beams are spatially correlated both in the near field and in the far field. Using realistic numerical simulations the performances of a quasithermal and a parametric down-conversion source are shown to be closely similar, both for what concerns the resolution and statistical properties. The results of this paper provide a scenario for the discussion of what role the entanglement plays in correlated imaging.
348 citations