{"results":[{"id":"ss_2fc7d040b64164126f0a56cf1562c7659bc2b146","title":"The quantum theory of light","authors":[{"name":"S. M. Barnett"},{"name":"John Jeffers"}],"abstract":"We present a brief introduction to the quantum theory of light as it is understood in the field of quantum optics. Our aim is not to review the topic, which would require a very extensive article (or even a book of several volumes) but rather to provide sufficient background to set the ideas in the following papers in their correct context. This article is part of the theme issue ‘The quantum theory of light’.","source":"Semantic Scholar","year":2024,"language":"en","subjects":["Medicine"],"doi":"10.1098/rsta.2023.0349","url":"https://www.semanticscholar.org/paper/2fc7d040b64164126f0a56cf1562c7659bc2b146","is_open_access":true,"citations":2407,"published_at":"","score":98},{"id":"ss_13492b77acd100ac6d07284eefd4b65a311ebdec","title":"Quantum Optics","authors":[{"name":"Jürgen Stuhler"},{"name":"A. Shields"}],"abstract":"1. Overview of classical optics from an advanced viewpoint 1.1. Notation and conventions for the electromagnetic field 1.2. Polarization properties of the free field 1.3. Spectral properties of the field 1.4. Wave propagation 2. Milestones in the quantum theory of light 2.1. Wien, Planck, Einstein, Bose, Dirac, Weyl 2.2. Interaction of light with a two-level system 3. Quantization of the electromagnetic field 3.1. Canonical quantization in the transverse gauge 3.2. Operator algebra and applications 3.3. Squeezed states – Poincaré pseudosphere 3.4. Entangled states 4. Quantum phase space descriptions 4.1. Wigner function and related non-classical distributions 4.2. Quantum phase space tomography 4.3. Equations of motion and the treatment of noise 5. (Quantum theory of the laser optional) 6. Quantum properties of ideal optical devices 6.1. Beam splitters, polarizers 6.2. Quantum logic elements 6.3. Quantum non-demolition measurement 7. Overview of nonlinear optics 7.1. Nonlinear susceptibility 7.2. Approximate methods for one-dimension 7.2.1. Harmonic generation, parametric oscillation, 7.2.2. Four-wave mixing 8. Quantum phenomena in nonlinear optics 8.1. Generation of squeezed states 8.2. Input-output theory 9. (Topics in quantum information theory – optional)","source":"Semantic Scholar","year":2019,"language":"en","subjects":null,"doi":"10.1142/9789812386199_others06","url":"https://www.semanticscholar.org/paper/13492b77acd100ac6d07284eefd4b65a311ebdec","is_open_access":true,"citations":5094,"published_at":"","score":93},{"id":"ss_31336553afcf3b0a4ea0079b6d44fb867d91308f","title":"Tissue Optics: Light Scattering Methods and Instruments for Medical Diagnosis","authors":[{"name":"V. Tuchin"}],"abstract":"","source":"Semantic Scholar","year":2000,"language":"en","subjects":["Materials Science"],"doi":"10.1117/3.1003040","url":"https://www.semanticscholar.org/paper/31336553afcf3b0a4ea0079b6d44fb867d91308f","is_open_access":true,"citations":1712,"published_at":"","score":80},{"id":"ss_142912073c3fb129f870a1df0aeaf344af588857","title":"Principles of optics : electromagnetic theory of propagation, interference and diffraction of light","authors":[{"name":"M. Born"},{"name":"E. Wolf"},{"name":"E. Hecht"}],"abstract":"","source":"Semantic Scholar","year":1999,"language":"en","subjects":["Physics"],"doi":"10.1063/1.1325200","url":"https://www.semanticscholar.org/paper/142912073c3fb129f870a1df0aeaf344af588857","pdf_url":"http://cds.cern.ch/record/396122/files/0521642221_TOC.pdf","is_open_access":true,"citations":4969,"published_at":"","score":80},{"id":"ss_bd57885fd2ea2dd4736608247786db9eee9ea4d9","title":"Principles of optics - electromagnetic theory of propagation, interference and diffraction of light (7. ed.)","authors":[{"name":"M. Born"}],"abstract":"","source":"Semantic Scholar","year":1999,"language":"en","subjects":["Physics","Computer Science"],"url":"https://www.semanticscholar.org/paper/bd57885fd2ea2dd4736608247786db9eee9ea4d9","is_open_access":true,"citations":2788,"published_at":"","score":80},{"id":"ss_fcf7a16c69bb6157b9920ea1c372562c9f3a583c","title":"Tunable structured light with flat optics","authors":[{"name":"A. Dorrah"},{"name":"F. Capasso"}],"abstract":"Flat optics has emerged as a key player in the area of structured light and its applications, owing to its subwavelength resolution, ease of integration, and compact footprint. Although its first generation has revolutionized conventional lenses and enabled anomalous refraction, new classes of meta-optics can now shape light and dark features of an optical field with an unprecedented level of complexity and multifunctionality. Here, we review these efforts with a focus on metasurfaces that use different properties of input light—angle of incidence and direction, polarization, phase distribution, wavelength, and nonlinear behavior—as optical knobs for tuning the output response. We discuss ongoing advances in this area as well as future challenges and prospects. These recent developments indicate that optically tunable flat optics is poised to advance adaptive camera systems, microscopes, holograms, and portable and wearable devices and may suggest new possibilities in optical communications and sensing. Description Actively structuring light The development of metasurfaces has provided a route to replacing bulk optical components with thin layers of engineered materials. In a review, Dorrah and Capasso highlight some of the recent advances in wavefront shaping using multifunctional meta-optics. They focus on the ability to tune the response of the metasurface by simply tuning one or more degrees of freedom of incident light, for example, by varying its angle of incidence, polarization, wavelength, or phase. The key feature of these metasurfaces is that although they are static, they can produce a tunable response without the need for complex switching. These developments enable multifunctional and lightweight components for technologies such as augmented and virtual reality displays, drone-based sensing, and endoscopy. —ISO A review discusses methods to control the functionality of optical metasurfaces by the incident light. BACKGROUND Structuring the degrees of freedom of light—including its phase, amplitude, and polarization—has opened new frontiers in science and technology alike. Adaptive cameras, microscopes, portable and wearable devices, optical communications, and laser machining are only a few of the domains that have evolved over the past decade owing to the advances in wavefront-shaping platforms. Flat optics composed of subwavelength-spaced optical scatterers—also known as metasurfaces or meta-optics—are key enabling tools for structured light not only for their compact footprint and complementary metal-oxide semiconductor (CMOS) compatibility but also because of their versatility and custom design. Although flat optics, or at least in its first generation, has led to the development of effects like anomalous refraction and diffraction-limited focusing, new classes of metasurfaces can now mold the flow of light in much more complex ways. Dispersion engineering and polarization optics are two prominent areas in which the metasurface’s ability to spatially manipulate each wavelength and/or polarization state, independently, cannot be paralleled using bulk optical components. At the heart of these developments is a carefully engineered light-matter interaction at the level of the meta-atom, which allows a passive metasurface to produce this complex response. ADVANCES The ability to manipulate light in different ways, depending on its properties, is intriguing because it allows a passive device to produce many functions without the need for active switching—that is, light itself can be used as an optical control knob. For example, the same flat optic may behave as a lens or a mirror depending on the incidence angle of light. Likewise, by changing light’s polarization, a metasurface can switch between different holograms or modify its focal length. In this spirit, a new generation of meta-optics can now perform parallel processing of the polarization of input light in the transverse plane or in 3D, reducing the function of many polarizers and waveplates into a single optical component that can be integrated in polarimeters and cellphone cameras. The spatial phase distribution of incoming light is another degree of freedom that can also be used as a switch, allowing a static flat optic to project different holograms by varying the helicity of the incident wavefront or its phase profile in general. Moreover, the ability to impart different phase and/or amplitude profiles on different wavelengths, independently, has enabled a wide class of versatile metalenses and compact pulse-shaping tools. Harnessing the nonlinear interaction of light with meta-atoms has also enabled multiwavelength holography on high harmonic-generated signals in addition to an asymmetric response. This versatility has made flat optics an ideal platform for the generation of structured light and has inspired many applications. The figure depicts the use of a metasurface as a multipurpose device (akin to a Swiss knife) that can mix and match output light by tuning the five abovementioned control knobs, without the need for any complex circuitry to drive the meta-atoms. Tunable behavior of this kind relies on an intricate light-matter interaction at the nanoscale, which is often difficult to replicate with other wavefront-shaping tools. With such tunability, many existing technologies can be dramatically miniaturized, enabling compact spectrometers, polarization-sensitive cameras, lightweight augmented reality and virtual reality headsets, and biomedical devices. OUTLOOK As the area of structured light matures, the quest for more sophisticated metasurfaces is also on the rise, aided by advanced nanofabrication, powerful computation capabilities for revealing new meta-atom libraries, and recent developments in actively tunable materials for time-varying control. Structured light with tunable metasurfaces is poised to reveal new functionalities and to replace conventional optical systems with on-chip photonic components. This includes integrating metasurfaces in laser cavities, Fabry-Perot resonators, fiber-based devices, and active wavefront-shaping tools. With the emerging trends in inverse design and topology optimization, new standardized protocols for large-scale multilayer metasurface fabrication and innovative material platforms will push the limits of multifunctional meta-optics and structured light from 2D to 3D and from static to animate, thus tackling the open challenges in this wide field of research and unlocking many new paths. Tunable structured light with static meta-optics. Different properties of input light may act as control knobs for tuning the optical response of the metasurface. These degrees of freedom include the angle of incidence (A), polarization state (B), orbital angular momentum (or spatial structure in general) (C), wavelength (D), and intensity level (manifested in a nonlinear interaction) (E). By changing one or more of these properties at the input of the metasurface, one can obtain a different light pattern at the output (depicted by the different puzzle pieces of Harvard University’s logo). This tunability relies on an intricate light-matter interaction at the level of the meta-atom, which often cannot be replicated by other conventional wavefront shaping platforms.","source":"Semantic Scholar","year":2022,"language":"en","subjects":["Medicine"],"doi":"10.1126/science.abi6860","url":"https://www.semanticscholar.org/paper/fcf7a16c69bb6157b9920ea1c372562c9f3a583c","is_open_access":true,"citations":355,"published_at":"","score":76.65},{"id":"ss_1ed8738f2806400dc94daa970f0e690fc4a4fd83","title":"Twisted Nano-optics: Manipulating Light at the Nanoscale with Twisted Phonon Polaritonic Slabs.","authors":[{"name":"J. Duan"},{"name":"N. Capote-Robayna"},{"name":"J. Taboada-Gutiérrez"},{"name":"G. Álvarez‐Pérez"},{"name":"I. Prieto"},{"name":"J. Martín-Sánchez"},{"name":"A. Nikitin"},{"name":"P. Alonso‐González"}],"abstract":"Recent discoveries have shown that when two layers of van der Waals (vdW) materials are superimposed with a relative twist angle between their respective in-plane principal axes, the electronic properties of the coupled system can be dramatically altered. Here, we demonstrate that a similar concept can be extended to the optics realm, particularly to propagating phonon polaritons - hybrid light-matter interactions -. To do this, we fabricate stacks composed of two twisted slabs of a polar vdW crystal (α-MoO3) supporting low-loss anisotropic phonon polaritons (PhPs), and image the propagation of the latter when launched by localized sources (metal antennas). Our images reveal that under a critical angle the PhPs isofrequency curve (determining the PhPs momentum at a fixed frequency) undergoes a topological transition. Remarkably, at this angle, the propagation of PhPs is strongly guided along predetermined directions (canalization regime) with no geometrical spreading (diffraction-less). These results demonstrate a new degree of freedom (twist angle) for controlling the propagation of polaritons at the nanoscale with potential for nano-imaging, (bio)-sensing, quantum applications and heat management.","source":"Semantic Scholar","year":2020,"language":"en","subjects":["Medicine","Physics"],"doi":"10.1021/acs.nanolett.0c01673","url":"https://www.semanticscholar.org/paper/1ed8738f2806400dc94daa970f0e690fc4a4fd83","pdf_url":"https://arxiv.org/pdf/2004.14599","is_open_access":true,"citations":187,"published_at":"","score":69.61},{"id":"doaj_10.1038/s41377-024-01730-9","title":"Real-time holographic camera for obtaining real 3D scene hologram","authors":[{"name":"Zhao-Song Li"},{"name":"Chao Liu"},{"name":"Xiao-Wei Li"},{"name":"Yi Zheng"},{"name":"Qian Huang"},{"name":"Yi-Wei Zheng"},{"name":"Ye-Hao Hou"},{"name":"Chen-Liang Chang"},{"name":"Da-Wei Zhang"},{"name":"Song-Lin Zhuang"},{"name":"Di Wang"},{"name":"Qiong-Hua Wang"}],"abstract":"Abstract As a frontier technology, holography has important research values in fields such as bio-micrographic imaging, light field modulation and data storage. However, the real-time acquisition of 3D scenes and high-fidelity reconstruction technology has not yet made a breakthrough, which has seriously hindered the development of holography. Here, a novel holographic camera is proposed to solve the above inherent problems completely. The proposed holographic camera consists of the acquisition end and the calculation end. At the acquisition end of the holographic camera, specially configured liquid materials and liquid lens structure based on voice-coil motor-driving are used to produce the liquid camera, so that the liquid camera can quickly capture the focus stack of the real 3D scene within 15 ms. At the calculation end, a new structured focus stack network (FS-Net) is designed for hologram calculation. After training the FS-Net with the focus stack renderer and learnable Zernike phase, it enables hologram calculation within 13 ms. As the first device to achieve real-time incoherent acquisition and high-fidelity holographic reconstruction of a real 3D scene, our proposed holographic camera breaks technical bottlenecks of difficulty in acquiring the real 3D scene, low quality of the holographic reconstructed image, and incorrect defocus blur. The experimental results demonstrate the effectiveness of our holographic camera in the acquisition of focal plane information and hologram calculation of the real 3D scene. The proposed holographic camera opens up a new way for the application of holography in fields such as 3D display, light field modulation, and 3D measurement.","source":"DOAJ","year":2025,"language":"","subjects":["Applied optics. Photonics","Optics. Light"],"doi":"10.1038/s41377-024-01730-9","url":"https://doi.org/10.1038/s41377-024-01730-9","is_open_access":true,"published_at":"","score":69},{"id":"ss_fdd41a37933033937263cf377b35696d4f48a4c6","title":"Nonlinear optics with structured light","authors":[{"name":"W. Buono"},{"name":"A. Forbes"}],"abstract":"","source":"Semantic Scholar","year":2022,"language":"en","subjects":null,"doi":"10.29026/oea.2022.210174","url":"https://www.semanticscholar.org/paper/fdd41a37933033937263cf377b35696d4f48a4c6","pdf_url":"https://www.oejournal.org/data/article/export-pdf?id=62b2cbe299d8816244ff952c","is_open_access":true,"citations":88,"published_at":"","score":68.64},{"id":"ss_71211a6d77860e7bb6b5c6a401acfcf7956c27ef","title":"Ultra-thin light-weight laser-induced-graphene (LIG) diffractive optics","authors":[{"name":"Younggeun Lee"},{"name":"Mun Ji Low"},{"name":"Dongwook Yang"},{"name":"Han-Ku Nam"},{"name":"Truong‐Son Dinh Le"},{"name":"Seung Eon Lee"},{"name":"Hyogeun Han"},{"name":"Seunghwan Kim"},{"name":"Quang Huy Vu"},{"name":"H. Yoo"},{"name":"H. Yoon"},{"name":"Joohyung Lee"},{"name":"S. Sandeep"},{"name":"Keunwoo Lee"},{"name":"Seung-Woo Kim"},{"name":"Young‐Jin Kim"}],"abstract":"The realization of hybrid optics could be one of the best ways to fulfill the technological requirements of compact, light-weight, and multi-functional optical systems for modern industries. Planar diffractive lens (PDL) such as diffractive lenses, photonsieves, and metasurfaces can be patterned on ultra-thin flexible and stretchable substrates and be conformally attached on top of arbitrarily shaped surfaces. In this review, we introduce recent research works addressed to the design and manufacturing of ultra-thin graphene optics, which will open new markets in compact and light-weight optics for next-generation endoscopic brain imaging, space internet, real-time surface profilometry, and multi-functional mobile phones. To provide higher design flexibility, lower process complexity, and chemical-free process with reasonable investment cost, direct laser writing (DLW) of laser-induced-graphene (LIG) is actively being applied to the patterning of PDL. For realizing the best optical performances in DLW, photon-material interactions have been studied in detail with respect to different laser parameters; the resulting optical characteristics have been evaluated in terms of amplitude and phase. A series of exemplary laser-written 1D and 2D PDL structures have been actively demonstrated with different base materials, and then, the cases are being expanded to plasmonic and holographic structures. The combination of these ultra-thin and light-weight PDL with conventional bulk refractive or reflective optical elements could bring together the advantages of each optical element. By integrating these suggestions, we suggest a way to realize the hybrid PDL to be used in the future micro-electronics surface inspection, biomedical, outer space, and extended reality (XR) industries. We present how direct-laser-writing can be utilized to fabricate ultra-thin light-weight planar diffractive optics with graphene as the base material. (Inset scale bar: 1 mm).","source":"Semantic Scholar","year":2023,"language":"en","subjects":["Medicine"],"doi":"10.1038/s41377-023-01143-0","url":"https://www.semanticscholar.org/paper/71211a6d77860e7bb6b5c6a401acfcf7956c27ef","pdf_url":"https://www.nature.com/articles/s41377-023-01143-0.pdf","is_open_access":true,"citations":53,"published_at":"","score":68.59},{"id":"doaj_10.1038/s41377-024-01618-8","title":"Color-conversion displays: current status and future outlook","authors":[{"name":"Guijun Li"},{"name":"Man-Chun Tseng"},{"name":"Yu Chen"},{"name":"Fion Sze-Yan Yeung"},{"name":"Hangyu He"},{"name":"Yuechu Cheng"},{"name":"Junhu Cai"},{"name":"Enguo Chen"},{"name":"Hoi-Sing Kwok"}],"abstract":"Abstract The growing focus on enhancing color quality in liquid crystal displays (LCDs) and organic light-emitting diodes (OLEDs) has spurred significant advancements in color-conversion materials. Furthermore, color conversion is also important for the development and commercialization of Micro-LEDs. This article provides a comprehensive review of different types of color conversion methods as well as different types of color conversion materials. We summarize the current status of patterning process, and discuss key strategies to enhance display performance. Finally, we speculate on the future prospects and roles that color conversion will play in ultra-high-definition micro- and projection displays.","source":"DOAJ","year":2024,"language":"","subjects":["Applied optics. Photonics","Optics. Light"],"doi":"10.1038/s41377-024-01618-8","url":"https://doi.org/10.1038/s41377-024-01618-8","is_open_access":true,"published_at":"","score":68},{"id":"ss_bf0ba1a4d865cdbe5a88ced55b58f62c8f603073","title":"Terahertz structured light: nonparaxial Airy imaging using silicon diffractive optics","authors":[{"name":"R. Ivaškevičiūtė-Povilauskienė"},{"name":"P. Kizevičius"},{"name":"E. Nacius"},{"name":"D. Jokubauskis"},{"name":"K. Ikamas"},{"name":"A. Lisauskas"},{"name":"N. Alexeeva"},{"name":"I. Matulaitienė"},{"name":"V. Jukna"},{"name":"S. Orlov"},{"name":"L. Minkevičius"},{"name":"G. Valušis"}],"abstract":"Structured light – electromagnetic waves with a strong spatial inhomogeneity of amplitude, phase, and polarization – has occupied far-reaching positions in both optical research and applications. Terahertz (THz) waves, due to recent innovations in photonics and nanotechnology, became so robust that it was not only implemented in a wide variety of applications such as communications, spectroscopic analysis, and non-destructive imaging, but also served as a low-cost and easily implementable experimental platform for novel concept illustration. In this work, we show that structured nonparaxial THz light in the form of Airy, Bessel, and Gaussian beams can be generated in a compact way using exclusively silicon diffractive optics prepared by femtosecond laser ablation technology. The accelerating nature of the generated structured light is demonstrated via THz imaging of objects partially obscured by an opaque beam block. Unlike conventional paraxial approaches, when a combination of a lens and a cubic phase (or amplitude) mask creates a nondiffracting Airy beam, we demonstrate simultaneous lensless nonparaxial THz Airy beam generation and its application in imaging system. Images of single objects, imaging with a controllable placed obstacle, and imaging of stacked graphene layers are presented, revealing hence potential of the approach to inspect quality of 2D materials. Structured nonparaxial THz illumination is investigated both theoretically and experimentally with appropriate extensive benchmarks. The structured THz illumination consistently outperforms the conventional one in resolution and contrast, thus opening new frontiers of structured light applications in imaging and inverse scattering problems, as it enables sophisticated estimates of optical properties of the investigated structures. Demonstration of generation of terahertz structured light in a form of configurable Airy beam for imaging aims and 2D materials inspection using exclusively flat silicon diffractive optics.","source":"Semantic Scholar","year":2022,"language":"en","subjects":["Medicine"],"doi":"10.1038/s41377-022-01007-z","url":"https://www.semanticscholar.org/paper/bf0ba1a4d865cdbe5a88ced55b58f62c8f603073","pdf_url":"https://www.nature.com/articles/s41377-022-01007-z.pdf","is_open_access":true,"citations":48,"published_at":"","score":67.44},{"id":"doaj_10.3390/opt4010012","title":"Innovative Approaches for Organizing an Inclusive Optics and Photonics Conference in Virtual Format","authors":[{"name":"Alba de las Heras"},{"name":"Ana I. Gómez-Varela"},{"name":"María-Baralida Tomás"},{"name":"Rosa Ana Perez-Herrera"},{"name":"Luis Alberto Sánchez"},{"name":"Francesca Gallazzi"},{"name":"Beatriz Santamaría Fernández"},{"name":"Mario Garcia-Lechuga"},{"name":"Maria Vinas-Pena"},{"name":"Martina Delgado-Pinar"},{"name":"Verónica González-Fernández"}],"abstract":"The COVID pandemic is forcing the renewal of scientific conferences, offering opportunities to introduce technological and inclusive developments. Our analysis focuses on the implementation of inclusive practices for female and early-career researchers in a virtual scientific conference. This organization approach was applied in the XIII Spanish Optical Meeting (RNO2021), which was also characterized by avatars interacting in an online metaverse. The effectiveness of inclusive policies and novel technological tools was evaluated using the participation data and a post-conference survey. Our study reveals the high impact of inclusive actions and a strong interest in the scientific community to explore conference advances.","source":"DOAJ","year":2023,"language":"","subjects":["Optics. Light","Applied optics. Photonics"],"doi":"10.3390/opt4010012","url":"https://www.mdpi.com/2673-3269/4/1/12","is_open_access":true,"published_at":"","score":67},{"id":"doaj_10.1016/j.pacs.2023.100452","title":"Fast iterative reconstruction for photoacoustic tomography using learned physical model: Theoretical validation","authors":[{"name":"Ko-Tsung Hsu"},{"name":"Steven Guan"},{"name":"Parag V. Chitnis"}],"abstract":"Iterative reconstruction has demonstrated superior performance in medical imaging under compressed, sparse, and limited-view sensing scenarios. However, iterative reconstruction algorithms are slow to converge and rely heavily on hand-crafted parameters to achieve good performance. Many iterations are usually required to reconstruct a high-quality image, which is computationally expensive due to repeated evaluations of the physical model. While learned iterative reconstruction approaches such as model-based learning (MBLr) can reduce the number of iterations through convolutional neural networks, it still requires repeated evaluations of the physical models at each iteration. Therefore, the goal of this study is to develop a Fast Iterative Reconstruction (FIRe) algorithm that incorporates a learned physical model into the learned iterative reconstruction scheme to further reduce the reconstruction time while maintaining robust reconstruction performance. We also propose an efficient training scheme for FIRe, which releases the enormous memory footprint required by learned iterative reconstruction methods through the concept of recursive training. The results of our proposed method demonstrate comparable reconstruction performance to learned iterative reconstruction methods with a 9x reduction in computation time and a 620x reduction in computation time compared to variational reconstruction.","source":"DOAJ","year":2023,"language":"","subjects":["Physics","Acoustics. Sound","Optics. Light"],"doi":"10.1016/j.pacs.2023.100452","url":"http://www.sciencedirect.com/science/article/pii/S2213597923000058","is_open_access":true,"published_at":"","score":67},{"id":"doaj_10.1016/j.pacs.2023.100535","title":"An extremum-guided interpolation for sparsely sampled photoacoustic imaging","authors":[{"name":"Haoyu Wang"},{"name":"Luo Yan"},{"name":"Cheng Ma"},{"name":"Yiping Han"}],"abstract":"In photoacoustic (PA) reconstruction, spatial constraints or real-time system requirements often result to sparse PA sampling data. For sparse PA sensor data, the sparse spatial and dense temporal sampling often leads to poor signal continuity. To address the structural characteristics of sparse PA signals, a data interpolation algorithm based on extremum-guided interpolation is proposed. This algorithm is based on the continuity of the signal, and can complete the estimation of high sampling rate signals without complex mathematical calculations. PA signal data is interpolated and reconstructed, and the results are evaluated using image quality assessment methods. The simulation and experimental results show that the proposed method performs better than several typical algorithms, effectively restoring image details, suppressing the generation of artifacts and noise, and improving the quality of PA reconstruction under sparse sampling.","source":"DOAJ","year":2023,"language":"","subjects":["Physics","Acoustics. Sound","Optics. Light"],"doi":"10.1016/j.pacs.2023.100535","url":"http://www.sciencedirect.com/science/article/pii/S2213597923000885","is_open_access":true,"published_at":"","score":67},{"id":"doaj_10.1038/s41377-022-01064-4","title":"Label-free imaging of red blood cells and oxygenation with color third-order sum-frequency generation microscopy","authors":[{"name":"Júlia Ferrer Ortas"},{"name":"Pierre Mahou"},{"name":"Sophie Escot"},{"name":"Chiara Stringari"},{"name":"Nicolas B. David"},{"name":"Laure Bally-Cuif"},{"name":"Nicolas Dray"},{"name":"Michel Négrerie"},{"name":"Willy Supatto"},{"name":"Emmanuel Beaurepaire"}],"abstract":"Color TSFG microscopy is a novel approach for label-free imaging of red blood cells and oxygenation in situ.","source":"DOAJ","year":2023,"language":"","subjects":["Applied optics. Photonics","Optics. Light"],"doi":"10.1038/s41377-022-01064-4","url":"https://doi.org/10.1038/s41377-022-01064-4","is_open_access":true,"published_at":"","score":67},{"id":"doaj_10.3390/opt4030036","title":"Photobiomodulation for Correction of Systemic Disorders of Experimental Pain Syndromes","authors":[{"name":"Alla G. Polyakova"},{"name":"Anna G. Soloveva"},{"name":"Petr V. Peretyagin"},{"name":"Anna N. Belova"},{"name":"Kseniya L. Belyaeva"}],"abstract":"The development of anti-pain technologies in the complex treatment of pain syndromes is one of the most urgent tasks of modern medicine. We undertook a placebo-controlled experimental study of the therapeutic potential of low-intensity laser radiation when applied to acupuncture points that are directly related to the autonomic nervous system. The adaptation effect of puncture photobiomodulation on the induction of stress-mediated autonomic reactions, oxidative metabolism and microcirculation in animals during the acute phase of pain stress was revealed. The data obtained are of interest for use in the complex rehabilitation of patients with pain syndromes.","source":"DOAJ","year":2023,"language":"","subjects":["Optics. Light","Applied optics. Photonics"],"doi":"10.3390/opt4030036","url":"https://www.mdpi.com/2673-3269/4/3/36","is_open_access":true,"published_at":"","score":67},{"id":"doaj_10.1016/j.rio.2023.100416","title":"Correlation between molar concentration and properties of sprayed copper oxide thin films","authors":[{"name":"F.O. Oluyemi"},{"name":"E.D. Ogunmola"},{"name":"A.A. Ajayi"},{"name":"O.C. Olawole"}],"abstract":"Copper oxide precursor solutions containing 0.10 M, 0.15 M, 0.20 M and 0.25 M concentration of copper were deposited on a glass substrate using the spray pyrolysis method. The structural, optical and surface properties of the resulting copper oxide thin films were studied using x-ray diffraction, UV–visible spectroscopy and scanning electron microscopy. Structural studies indicate the absence of secondary phases of copper oxide in the spray-deposited copper oxide thin film with 0.10 M concentration. Optical characterization reveals highest absorbance and lowest transmittance at 0.10 M concentration with an estimated optical bandgap of 1.2 eV. The SEM micrographs reveals a non-porous and comparatively more homogenous surface at 0.10 M concentration. The results show that molar concentration of copper plays a vital role in the development of copper oxide (CuO) thin film for solar cell application. The results have further validated the theoretical predictions of the GW approximations on phases of copper oxide thin films.","source":"DOAJ","year":2023,"language":"","subjects":["Optics. Light"],"doi":"10.1016/j.rio.2023.100416","url":"http://www.sciencedirect.com/science/article/pii/S2666950123000688","is_open_access":true,"published_at":"","score":67},{"id":"doaj_10.29026/oea.2023.220008","title":"Ostensibly perpetual optical data storage in glass with ultra-high stability and tailored photoluminescence","authors":[{"name":"Zhuo Wang"},{"name":"Bo Zhang"},{"name":"Dezhi Tan"},{"name":"Jianrong Qiu"}],"abstract":"Long-term optical data storage (ODS) technology is essential to break the bottleneck of high energy consumption for information storage in the current era of big data. Here, ODS with an ultralong lifetime of 2×107 years is attained with single ultrafast laser pulse induced reduction of Eu3+ ions and tailoring of optical properties inside the Eu-doped aluminosilicate glasses. We demonstrate that the induced local modifications in the glass can stand against the temperature of up to 970 K and strong ultraviolet light irradiation with the power density of 100 kW/cm2. Furthermore, the active ions of Eu2+ exhibit strong and broadband emission with the full width at half maximum reaching 190 nm, and the photoluminescence (PL) is flexibly tunable in the whole visible region by regulating the alkaline earth metal ions in the glasses. The developed technology and materials will be of great significance in photonic applications such as long-term ODS.","source":"DOAJ","year":2023,"language":"","subjects":["Optics. Light"],"doi":"10.29026/oea.2023.220008","url":"https://www.oejournal.org/article/doi/10.29026/oea.2023.220008","is_open_access":true,"published_at":"","score":67},{"id":"ss_ac125208afafb95cb92b6ee2550b562d8c981d64","title":"Quantum delocalization, gauge, and quantum optics: Light-matter interaction in relativistic quantum information","authors":[{"name":"R. Lopp"},{"name":"Eduardo Mart'in-Mart'inez"}],"abstract":"We revisit the interaction of a first-quantized atomic system (consisting of two charged quantum particles) with the quantum electromagnetic field, pointing out the subtleties related to the gauge nature of electromagnetism and the effect of multipole approximations. We connect the full minimal-coupling model with the typical effective models used in quantum optics and relativistic quantum information such as the Unruh-DeWitt (UDW) model and the dipole coupling approximation. We point out in what regimes different degrees of approximation are reasonable and in what cases effective models need to be refined to capture the features of the light-matter interaction. This is particularly important when considering the center of mass (COM) of the atom as a quantum system that can be delocalized over multiple trajectories. For example, we show that the simplest UDW approximation with a quantum COM fails to capture crucial R\\\"ontgen terms coupling COM and internal atomic degrees of freedom with each other and the field. Finally we show how effective dipole interaction models can be covariantly prescribed for relativistically moving atoms.","source":"Semantic Scholar","year":2020,"language":"en","subjects":["Physics"],"doi":"10.1103/PHYSREVA.103.013703","url":"https://www.semanticscholar.org/paper/ac125208afafb95cb92b6ee2550b562d8c981d64","pdf_url":"https://arxiv.org/pdf/2008.12785","is_open_access":true,"citations":70,"published_at":"","score":66.1}],"total":5747321,"page":1,"page_size":20,"sources":["DOAJ","CrossRef","Semantic Scholar"],"query":"Optics. Light"}