样式: 排序: IF: - GO 导出 标记为已读
-
Archimedes spiral beam: composite of a helical-axicon generated Bessel beam and a Gaussian beam J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-04-23 Zhoulin Ding and Yongji Yu
This paper introduces a structured beam with Archimedes spiral intensity distribution. The Archimedes spiral (AS) beam is the composite of a helical-axicon generated (HAG) Bessel beam and a Gaussian (GS) beam. We observed the spiral intensity patterns using computational holography, achieving the tuning over spiral arms number and spiral spacing. Analyzing the propagation dynamics of AS beams, we present
-
Effect of an aperture in atomic gravimetry J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-04-23 J. M. Cervantes and E. Gomez
There is a continuous interest in shrinking the dimensions of portable atomic gravimeters. This inevitably ends up truncating the Gaussian wings of the excitation laser beams whose effect has not been properly quantified yet. The diffraction pattern created from this aperture creates ripples in the wavefront in both the phase and the intensity. We calculate the shift in the measured value of an atomic
-
Experimental investigation on backscattering interference cancellation for full-duplex UOWC based on time-reversal preprocessing J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-04-16 Weijie Liu, Shuzhe Zhang, Nuo Huang, and Zhengyuan Xu
A co-frequency and full-duplex (FD) underwater optical wireless communication (UOWC) system has the potential to significantly enhance spectral efficiency, reduce complexity, and further facilitate UOWC networking. However, the inevitable performance degradation due to self-interference introduced by backscattering presents a significant challenge. In this paper, we first experimentally explore the
-
Fluorescence molecular tomography based on an online maximum a posteriori estimation algorithm J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-04-16 Xia Cheng, Siyu Sun, Yinglong Xiao, Wenjing Li, Jintao Li, Jingjing Yu, and Hongbo Guo
Fluorescence molecular tomography (FMT) is a non-invasive, radiation-free, and highly sensitive optical molecular imaging technique for early tumor detection. However, inadequate measurement information along with significant scattering of near-infrared light within the tissue leads to high ill-posedness in the inverse problem of FMT. To improve the quality and efficiency of FMT reconstruction, we
-
Quaternion fast and accurate polar harmonic Fourier moments for color image analysis and object recognition J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-04-16 Siyu Yang and Ansheng Deng
Image moments, as a kind of global feature descriptor of images, have become a valuable tool for pattern recognition and image analysis. However, traditional methods are mainly used to deal with grayscale images. In this paper, we apply quaternions to fast and accurate polar harmonic Fourier moments, proposing a kind of quaternion fast and accurate polar harmonic Fourier moment (QFAPHFM) capable of
-
Minimizing optical attribute errors for a lane departure warning system using an ultra-wide-angle camera J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-04-16 Hyungtae Kim and Joonki Paik
Advanced driver assistance systems (ADAS) rely on lane departure warning (LDW) technology to enhance safety while driving. However, the current LDW method is limited to cameras with standard angles of view, such as mono cameras and black boxes. In recent times, more cameras with ultra-wide-angle lenses are being used to save money and improve accuracy. However, this has led to some challenges such
-
Relationship between turbulent image variance and average image gradient J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-04-15 Guy Potvin
Optical turbulence can cause substantial distortions in imaging over long horizontal paths. For Lambertian objects, these distortions are only seen where there is a gradient in the object’s radiance. It is possible to establish a relationship between the intensity variance of a turbulent image and the average image’s gradient squared. We test the validity of a linear relationship between these quantities
-
Advanced linear axial wavelength spreading through cascaded double hyperchromats J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-04-15 Lukas Werner, Hartmut Hillmer, and Robert Brunner
This study explores the design and optimization of cascaded double-hyperchromatic optical systems (i.e., {2} \times {2} lenses), focusing on achieving an extremely linear axial spectral decomposition characterized by an exceptionally low equivalent Abbe number. The investigation involves two double hyperchromats, considering both purely refractive systems and hybrid configurations that combine refractive
-
Effect of surface anchoring energy on a liquid crystal optical waveguide-based polarization rotator J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-04-11 Zhengtao Zha
This study reports the effect of the surface anchoring energy of a liquid crystal (LC) cell on the performance of the liquid crystal optical waveguide polarization rotator (LCOW-PR) for the purpose of providing a theoretical reference for practical preparation of the LCOW-PR. First, the expression for the deflection angle of the director at the boundary of the LC cell is derived so that the distributions
-
Simulating a turbulent video affected by spatiotemporally varying blur and tilt using temporal cross correlation of intermodal Zernike coefficients J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-04-10 Or Maor and Yitzhak Yitzhaky
Videos captured in long-distance horizontal imaging through the atmosphere suffer from dynamic spatiotemporal movements and blur caused by the air turbulence. Simulations of atmospheric turbulence in such videos, which have been conducted in the past, are difficult to compute. Our goal in this research is to develop an effective simulation algorithm of videos affected by atmospheric turbulence characterized
-
Ultra-high order mode-assisted optical differentiator for edge detection with high tunability J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-04-10 Chengyu Wu, Yanbin Tang, Jian Shi, Cuicui Li, Wenli He, Gangbin Xu, Jian Wu, and Xianping Wang
An optical spatial differentiator based on the photonic spin Hall effect (PSHE) with high tunability is presented. By utilizing the characteristics of ultra-high order modes in the symmetrical metal cladding waveguide, the Fresnel reflection coefficient spectrum exhibits a narrow peak width and low trough at the resonant incident angles, resulting in high sensitivity to changes in the incident angle-induced
-
Optimized Stokes imaging for highly resolved optical speckle fields, Part I: optimized experimental setup J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-04-10 Jonathan Staes and Julien Fade
In this first article of a three-part series focusing on the Stokes polarimetry of optical speckle fields resolved at the individual speckle grain scale, a review of the state-of-the-art techniques for such experimental investigations is provided. An optimized experimental setup is then extensively described, which allows polarimetric Stokes measurements on such complex interference patterns to be
-
Optimized Stokes imaging for highly resolved optical speckle fields, Part II: optimal acquisition and estimation strategies J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-04-10 Jonathan Staes and Julien Fade
In this second paper of a three-paper series focusing on Stokes polarimetry of optical speckle fields resolved at the individual speckle grain scale, a theoretical study based on numerical simulations is presented in order to establish the optimum sensing, estimation, and processing strategies that guarantee the best precision, accuracy, and robustness for Stokes polarimetry in this specific context
-
Optimized Stokes imaging for highly resolved optical speckle fields, Part III: topological analysis of polarimetric state distributions with optimized data representations J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-04-10 Jonathan Staes and Julien Fade
In this last article of a three-paper series focusing on Stokes polarimetry of optical speckle fields resolved at the individual speckle grain scale, experimental results are provided on test samples of varying nature and polarization properties, and are analyzed extensively. For this purpose, a review of the classical ways of displaying Stokes polarimetric information is provided. Then, some original
-
Res-U2Net: untrained deep learning for phase retrieval and image reconstruction J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-04-08 Carlos Osorio Quero, Daniel Leykam, and Irving Rondon Ojeda
Conventional deep learning-based image reconstruction methods require a large amount of training data, which can be hard to obtain in practice. Untrained deep learning methods overcome this limitation by training a network to invert a physical model of the image formation process. Here we present a novel, to our knowledge, untrained Res-U2Net model for phase retrieval. We use the extracted phase information
-
Matrix-based integral transformations for Stokes imaging with partially polarized and partially coherent light J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-04-08 Wei Wang and Mitsuo Takeda
With the aid of the matrix-based integral transforms called matrix convolution and matrix direct correlation, we provide a simplified expression for the space- and frequency-domain calculations of polarization imaging with partially polarized and partially coherent light. As an example of practical interest, a formula for Stokes imaging, based on the generalized Stokes parameters, is presented, in
-
Dynamic iterative correction algorithm for designing diffractive optical elements J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-04-05 Chi Hu, Jin Zhang, Shilei Jiang, and Guobin Sun
When utilizing the Gerchberg–Saxton (GS) algorithm to design diffractive optical elements, correction coefficients are introduced to improve the quality of the design results. The main design idea is to correct the target information dynamically during the iterative calculation process. The effectiveness of the proposed method is demonstrated through the verification of beam shaping and phase-type
-
Design of a dual hollow beam optical antenna based on a Fresnel lens-conical lens combination J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-04-03 Yunlong Li, Liang Zhong, Shuaikang Fu, Yan Qin, Jianing Liu, Ping Jiang, and Huajun Yang
To improve the transmission efficiency of Cassegrain antennas and enable the simultaneous transmission of signals with different wavelengths in the antenna system, this study introduces Fresnel lenses and conical lenses in front of the Cassegrain antenna at the transmitting end. Reflective mirrors and focusing lenses are introduced at the receiving end. A detailed description is provided of the design
-
EFNet: enhancing feature information for 3D object detection in LiDAR point clouds J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-03-28 Xin Meng, Yuan Zhou, Kaiyue Du, Jun Ma, Jin Meng, Aakash Kumar, Jiahang Lv, Jonghyuk Kim, and Shifeng Wang
With the development of autonomous driving, there has been considerable attention on 3D object detection using LiDAR. Pillar-based LiDAR point cloud detection algorithms are extensively employed in the industry due to their simple structure and high real-time performance. Nevertheless, the pillar-based detection network suffers from significant loss of 3D coordinate information during the feature degradation
-
Influence of corneal astigmatism on near and far vision in eyes with bifocal intraocular lenses J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-03-27 Jongin You and Mooseok Jang
Here, we present a full wave propagation model that quantitatively assesses the effect of astigmatism on visual functions in eyes with diffractive bifocal IOLs. The proposed model with bifocal IOLs evaluated the image quality of each focus at varying degrees of corneal astigmatism with the metrics of modulation transfer function and light-in-the-bucket. The results show that corneal astigmatism alters
-
Stokes vector characterization by strongly measuring weak values J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-03-25 C. Montenegro, M. Jara, J. P. Marrou, and F. De Zela
We report the implementation of a non-standard procedure to perform Stokes polarimetry, which was recently proposed by considering weak value measurements. Our procedure is not restricted to weak measurements but applies for both weak and strong couplings between the observable being measured; the polarization (spin) vector; and the measuring device, the “pointer.” In optics, the polarization-pointer
-
Degree of paraxiality of radially polarized twisted multi-Gaussian Schell-model beams J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-03-21 Jinping Cheng, Yin Feng, Hao Wu, Tao Wang, and Miaomiao Tang
The degree of paraxiality (DOP) of a radially polarized twisted multi-Gaussian Schell-model (RPT MGSM) beam is discussed, and the influence of the source parameters on its DOP is studied. It is shown that the parameters of the beam source, including the boundary characteristic, the beam waist width, the coherence width of the source correlation, and the twist factor, have a significant impact on the
-
Utilizing Joukowsky transformation in the design of optical fiber for elliptical-to-circular mode conversion J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-03-21 Shuaikang Fu, Ping Jiang, Yan Qin, Jianing Liu, and Huajun Yang
This study addresses the challenge of enhancing coupling efficiency between optical fibers and elliptical Gaussian beams emitted by semiconductor lasers, particularly in fiber communication systems. We introduce a method for fiber design utilizing the Joukowsky transformation to facilitate efficient mode transformation from elliptical to circular, thereby augmenting the coupling efficiency with both
-
Generalized neutral axes in nondepolarizing optical systems J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-03-21 Guy Perrin
The polarizing properties of optical systems are often characterized by their action on specific polarization states. For example, half-wave plates are used to rotate linear polarizations and quarter-wave plates to turn a linear polarization into an elliptical polarization and into a circular polarization if the linear polarization makes a 45° angle with the slow and fast axes of the quarter-wave plate
-
Diffraction of a pseudo nondiffracting Bessel beam by a circular perfect electromagnetic conductor disk J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-03-21 Husnu Deniz Basdemir
This study examined the diffraction of a pseudo nondiffracting Bessel beam by a perfect electromagnetic disk. The geometric optics beam waves were written from the geometry of the problem and related boundary conditions. The diffracted beam waves were derived by utilizing the relation between geometric optics and diffracted waves at the transition boundaries, considering the high frequency asymptotic
-
Nonparaxial accelerating waves as a superposition of nondiffracting Bessel-lattice optical fields J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-03-21 Israel Julián-Macías, Gabriel Martínez-Niconoff, Gilberto Silva-Ortigoza, and Carolina Rickenstorff-Parrao
In the first part of this work, we introduce a monochromatic solution to the scalar wave equation in free space, defined by a superposition of monochromatic nondiffracting half Bessel-lattice optical fields, which is determined by two scalar functions; one is defined on frequency space, and the other is a complete integral to the eikonal equation in free space. We obtain expressions for the geometrical
-
Wavefront aberration determination in non-axially symmetrical optical systems J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-03-18 Psang Dain Lin
Non-axially symmetrical optical systems can provide better solutions to several optical design problems. However, determining their wavefront aberrations is challenging due to the great diversity of their configurations. Accordingly, in the present study, the optical path length (OPL) between two boundaries in a non-axially symmetrical system is expanded by a Taylor series expansion with respect to
-
Neural network classification of beams carrying orbital angular momentum after propagating through controlled experimentally generated optical turbulence J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-03-14 William A. Jarrett, Svetlana Avramov-Zamurovic, Joel M. Esposito, K. Peter Judd, and Charles Nelson
We generate an alphabet of spatially multiplexed Laguerre–Gaussian beams carrying orbital angular momentum, which are demultiplexed at reception by a convolutional neural network (CNN). In this investigation, a methodology for optimizing alphabet design for best classification rates is proposed, and three 256-symbol alphabets are designed for performance evaluation in optical turbulence. The beams
-
High-sensitivity refractive index sensor based on strong localized surface plasmon resonance J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-03-15 Hanwen Chen, Xiangxian Wang, Yizhen Chen, Xijun Rao, Huirong Zhu, Hua Yang, and Yunping Qi
This study proposes two types of composite structures based on gold nano circular and nano square rings on a gold thin film for plasmonic refractive index sensing. The finite-difference time-domain method was used for simulation and analysis. The nano square ring composite structure showed superior performance, with five surface plasmon resonance modes, and a peak sensitivity and figure of merit in
-
Bootstrap geometric ground calibration method for wide angle star sensors J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-03-15 Samuel Teague and Javaan Chahl
Wide angle star sensors are becoming more prevalent in aeronautics. A wide angle lens provides a greater field of view for star detection, but consequently incurs significant lens distortion. The effects of distortion complicate star identification, causing algorithms to fail or report false identifications. We address the issue of calibrating a wide angle star sensor without any specialized equipment
-
Polarization coherence frustration J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-03-14 Philippe Réfrégier and Julien Fade
From the joint analysis of polarization and coherence properties of light, a remarkable concept referred to as polarization coherence frustration is introduced and analyzed. It is shown that two kinds of partially polarized and partially coherent light, with different levels of complexity, can be distinguished and that they mathematically correspond to different equivalence classes. On the one hand
-
Multispectral image defogging based on a wavelength-dependent extinction coefficient model in fog J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-03-13 Feng Huang, Chaozhen Ke, Xianyu Wu, Cuixia Guo, and Yu Liu
Most of the state-of-the-art defogging models presented in the literature assume that the attenuation coefficient of all spectral channels is constant, which inevitably leads to spectral distortion and information bias. To address this issue, this paper proposes a defogging method that takes into account the difference between the extinction coefficients of multispectral channels of light traveling
-
Nonstationary optics: tutorial J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-03-11 Matias Koivurova, Jyrki Laatikainen, and Ari T. Friberg
Over the past several decades, nonstationary optics has risen as a key enabling technology for a multitude of novel applications. These include areas of research such as micromachining and ultrafast optics, as well as the Nobel awarded research in femtochemistry, optical frequency combs, and attosecond physics. This tutorial aims to present some of the main concepts required to analyze nonstationary
-
Optimization analysis of a Stokes polarimeter for broadband liquid crystal variable retarders under the optimal objective function J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-03-08 Lingying Chang, Jiayi Li, Youbiao Zhang, Yuping Yin, and Jingyi Liu
A liquid crystal variable retarder (LCVR) is the core device to realize fast and high-precision broadband polarization imaging, and its ability to suppress the noise will have an impact on the polarization measurement results. In order to obtain better imaging quality and measurement accuracy, it is crucial to solve the optimization problem of the LCVR. In this paper, the optimal objective function
-
Absorption-invariant focusing efficiency for wavefront-shaping controlled reflection from absorbing disordered media J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-03-06 Benjamin R. Anderson, Ray Gunawidjaja, and Hergen Eilers
We numerically model the influence of absorption on wavefront-shaping controlled reflection from absorbing disordered media and provide experimental verification of our model. We find that absorption modifies the reflection eigenvalue density, the average reflectance, and the reflection matrix element density. However, we also find that despite these effects, the efficiency of wavefront-shaping controlled
-
High-sensitivity dual U-shaped PCF-SPR refractive index sensor for the detection of gas and liquid analytes J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-03-06 Xingdi Luo, Wei Liu, Jingwei Lv, Lin Yang, Jianxin Wang, Paul K. Chu, and Chao Liu
A dual U-shaped photonic crystal fiber (PCF) biochemical sensor based on surface plasmon resonance (SPR) is designed for the simultaneous detection of gas and liquid analytes, and the properties are analyzed by the full vector finite element method (FEM). SPR is excited by placing gold nanowires on the inner surface of the U-shaped device. In this technique, the traditional metal deposition process
-
Extended just-noticeable difference for ultralow-luminance displays used in diagnostic imaging J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-03-04 Takushi Kawamorita, Tetsuya Yasuda, Takashi Ota, Tatsuya Iizuka, Makiko Miyasaka, Noritaka Mamorita, and Tomoya Handa
This study investigates the just-noticeable difference (JND) in luminance below the 0.050cd/m2 threshold not covered by the DICOM standard in medical imaging displays. A total of 21 healthy young adults were tested using an ultralow-luminance liquid crystal display at a viewing distance of 46 cm. The optotype featured a 4 cycle/deg rectangular wave-like stripe. The average percentage of correct responses
-
Matrix formulation of the Gaussian expansion of coherent multiple beams in arbitrary dimensions J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-27 H. Coïc, Y. Abdelmoumni-Prunes, C. Rouyer, and N. Bonod
Modeling the propagation of beams along laser beamlines is very challenging due to the multidimensional and multiscale configuration of the problem. Spatio-temporal couplings are particularly difficult to address with conventional numerical methods. Here we derive the Wigner function of a sum of Gaussian beams by calculating the multidimensional Fourier transform of the intercorrelation function of
-
Digital Holography and 3D Imaging: introduction to the joint feature issue in Applied Optics and Journal of the Optical Society of America A J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-26 Pierre-Alexandre Blanche, Chau-Jern Cheng, Pietro Ferraro, Yaping Zhang, and Zhehui (Jeph) Wang
The Optica Topical Meeting on Digital Holography and 3D Imaging (DH) was held 14–17 August 2023 in Boston, Massachusetts. The meeting was organized co-jointly with the Optica Imaging Congress. Feature issues based on the DH meeting series have been released by Applied Optics (AO) since 2007. Since 2017, AO and the Journal of the Optical Society of America A (JOSA A) have presented a feature issue in
-
Center extraction method for reflected metallic surface fringes based on line structured light J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-26 Limei Song, Jinsheng He, and Yunpeng Li
Using line structured light to measure metal surface topography, the extraction error of the stripe center is significant due to the influence of the optical characteristics of the metal surface and the scattering noise. This paper proposes a sub-pixel stripe center extraction method based on adaptive threshold segmentation and a gradient weighting strategy to address this issue. First, we analyze
-
Single-stage approach for estimating optical parameters in spectral quantitative photoacoustic tomography J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-26 Miika Suhonen, Aki Pulkkinen, and Tanja Tarvainen
In quantitative photoacoustic tomography, the optical parameters of a target, most importantly the concentrations of chromophores such as deoxygenated and oxygenated hemoglobin, are estimated from photoacoustic data measured on the boundary of the target. In this work, a numerical approximation of a forward model for spectral quantitative photoacoustic tomography is constructed by utilizing the diffusion
-
Propagation properties of elegant modified Bessel Gaussian beams J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-26 Chaohong Huang, Xiao Liu, Yanjing Li, Yutian Lin, Yangying Xu, Kunmin Yang, and Yongtong Zhao
A kind of optical beam with a radially parabolic propagating manner and intensity decay inversely proportional to propagating distance in the far field is investigated. The initial complex amplitudes of this kind of beam have the form of a Gaussian function multiplied by a m/2 -order modified Bessel function and a helical phase factor with topological charge m . The arguments for Bessel and Gauss parts
-
Psychophysical determination of boundaries and smoothness of color gradients J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-27 Nian Xiong and Renzo Shamey
Color gradients constitute an important component in the evaluation of the color quality of multicolored patterns that contain color transitions. A two-part psychophysical study was designed and employed to test the appearance of a set of hue-, chroma-, or lightness-based color gradients. The influence of several parameters on the visual determination of gradients’ boundaries and perceived smoothness
-
Affine diffractive beam dividers J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-22 F. Gori, R. Martínez-Herrero, O. Korotkova, G. Piquero, J. C. G. de Sande, G. Schettini, F. Frezza, and M. Santarsiero
Diffractive optical elements that divide an input beam into a set of replicas are used in many optical applications ranging from image processing to communications. Their design requires time-consuming optimization processes, which, for a given number of generated beams, are to be separately treated for one-dimensional and two-dimensional cases because the corresponding optimal efficiencies may be
-
Improving RGB illuminant estimation exploiting spectral average radiance J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-22 Ilaria Erba, Marco Buzzelli, Jean-Baptiste Thomas, Jon Yngve Hardeberg, and Raimondo Schettini
We introduce a method that enhances RGB color constancy accuracy by combining neural network and k -means clustering techniques. Our approach stands out from previous works because we combine multispectral and color information together to estimate illuminants. Furthermore, we investigate the combination of the illuminant estimation in the RGB color and in the spectral domains, as a strategy to provide
-
Dynamic projection mapping for non-planar objects with a variable focus lens and visual feedback J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-20 Shangen Tang, Lihui Wang, Fengnian Song, and Shaoyong Li
Dynamic projection mapping for moving objects has attracted much attention in recent years. However, conventional approaches have faced some issues, such as the target objects being limited to the moving speed of the objects, the limitation of the narrow depth-of-field optics, and the planar shape objects. This work proposed an adaptive three-dimensional projection prototype, and it could project an
-
Real-time binocular visual localization system based on the improved BGNet stereo matching framework J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-20 Zanxi Qu, Li Li, Weiqi Jin, and Ye Yang
Binocular vision technology is widely used to acquire three-dimensional information of images because of its low cost. In recent years, the use of deep learning for stereo matching has shown promising results in improving the measurement stability of binocular vision systems, but the real-time performance in high-precision networks is typically poor. Therefore, this study constructed a deep-learning-based
-
Phasing segmented telescopes via deep learning methods: application to a deployable CubeSat J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-20 Maxime Dumont, Carlos M. Correia, Jean-François Sauvage, Noah Schwartz, Morgan Gray, and Jaime Cardoso
Capturing high-resolution imagery of the Earth’s surface often calls for a telescope of considerable size, even from low Earth orbits (LEOs). A large aperture often requires large and expensive platforms. For instance, achieving a resolution of 1 m at visible wavelengths from LEO typically requires an aperture diameter of at least 30 cm. Additionally, ensuring high revisit times often prompts the use
-
Nighttime color constancy using robust gray pixels J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-20 Cheng Cheng, Kai-Fu Yang, Xue-Mei Wan, Leanne Lai Hang Chan, and Yong-Jie Li
Color constancy is a basic step for achieving stable color perception in both biological visual systems and the image signal processing (ISP) pipeline of cameras. So far, there have been numerous computational models of color constancy that focus on scenes under normal light conditions but are less concerned with nighttime scenes. Compared with daytime scenes, nighttime scenes usually suffer from relatively
-
Design methodology for catadioptric zoom panoramic optical systems based on image plane bending matched correction J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-15 ZhiYing Liu, ShaoKang Jin, YunHan Huang, and SongKun Liu
Zoom panoramic optical systems incorporate a panoramic peripheral vision zoom imaging function, enabling swift wide-area coarse and localized precise detection. These systems find applicability in examining pipes and other internal structures. This study centers on the catadioptric zoom panoramic optical system and its associated optical design method. A mathematical model of the front mirror was formulated
-
Improving energy efficiency: a highly efficient coaxial design for a laser ranging system with a splicing lens J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-15 Shuixin Pan, Jinlin Cui, Yueqiang Zhang, Biao Hu, Xiaolin Liu, and Qifeng Yu
Light detection and ranging (LiDAR) systems have made significant contributions in different applications. The laser ranging (LR) system is one of the core components of LiDARs. However, existing coaxial LR systems suffer from low energy efficiency due to obstruction of the reflection mirror. In this study, we carefully design a laser transmitter and receiver subsystem and consequently propose a highly
-
Modeling and oblique transmission characteristics of an underwater wireless optical communication channel based on ocean depth layering J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-13 Dan Chen, Peiyan Zhao, Linhai Tang, and Minyan Wang
Underwater wireless optical communication is widely considered in the field of underwater communication due to its high bandwidth and low latency. In a real transmission link, the temperature and salinity of seawater, chlorophyll concentration, and bubble density vary with ocean depth. Therefore, the depth of the optical transmitter in seawater and the tilt angle of the beam will exhibit different
-
Visions of invisibility in optics: retrospective J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-13 Greg Gbur
Invisibility was long thought to be exclusively the domain of science fiction and fantasy authors, but in recent years it has been the subject of extensive theoretical and experimental research. In this retrospective we look back on the evolution of invisibility in science, from the earliest hints of invisible objects in the late 19th century up to the modern concepts of cloaking, and some of the connections
-
Binary image encryption with a QR code-encoded optical beam having an array of vortices J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-13 Allarakha Shikder, Sonu Kumar Rao, Praveen Kumar, and Naveen K. Nishchal
In recent years, optical information processing has become increasingly important due to its ability to handle large amounts of data efficiently. Amplitude, phase, spatial frequency, wavelength, and polarization are the physical dimensions used for information encoding into the light beam. Information encoding using orbital angular momentum (OAM) carried by a vortex beam is gaining interest in this
-
Enhancing 3D human pose estimation with NIR single-pixel imaging and time-of-flight technology: a deep learning approach J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-13 Carlos Osorio Quero, Daniel Durini, Jose Rangel-Magdaleno, Jose Martinez-Carranza, and Ruben Ramos-Garcia
The extraction of 3D human pose and body shape details from a single monocular image is a significant challenge in computer vision. Traditional methods use RGB images, but these are constrained by varying lighting and occlusions. However, cutting-edge developments in imaging technologies have introduced new techniques such as single-pixel imaging (SPI) that can surmount these hurdles. In the near-infrared
-
Multiuser medical image encryption algorithm using phase-only CGH in the gyrator domain J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-07 Raman Yadav, Sachin, and Phool Singh
In this paper, a multiuser medical image encryption algorithm is proposed. The proposed algorithm utilizes polar decomposition, which enables multiuser features in the proposed algorithm. A computer-generated hologram (CGH) improves the security of the proposed algorithm in the gyrator domain. The phase-only CGH-based multiuser algorithm offers advantages such as storing a large amount of information
-
Point cloud holographic encryption display system involving 3D face recognition and air-writing J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-06 Jia-Hui Ji, Yu Zhao, Jing-Wen Bu, Tao Zhang, Li Ming Zhu, and Yuan Huang
In this study, we proposed a holographic identity verification encryption system that integrates face recognition, air-writing, and the multiple point cloud gridding encryption (M-PCGE) method to ensure multi-level security for objects. The experimental results show that the M-PCGE algorithm proposed in this paper achieves image encryption and decryption quickly with a high degree of restoration, and
-
Real-time phase retrieval in division of aperture microscopy with the transport of intensity equation J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-06 Ariel Fernández, Juan M. Llaguno, Alejandro Silva, and Julia R. Alonso
The transport of intensity equation (TIE) allows to recover the phase of a microscopy sample from differently focused intensity measures along the axial direction of its optical field. In the present work, we propose a cost-effective technique for snapshot phase retrieval with TIE. The optics of a commercially available camera is replaced with a doublet system consisting of a microscope objective and
-
Dish spliced concentrator with both uniform and focused performance through a variable focal length J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-06 Peiyuan Wang, Shuaikang Fu, Ping Jiang, Yan Qin, Jianing Liu, Chaoxiang Wang, Chenxi Bai, and Huajun Yang
We present a dish spliced concentrator (DSC) featuring hexagonal spherical sub-mirrors of uniform size. The DSC offers advantages over traditional parabolic dish concentrators, including a compact layout, cost-effectiveness, higher concentration ratio, and improved light uniformity. Its versatility allows for both uniform and focused light concentration by adjusting parameters like the focal length
-
Exciting space-time surface plasmon polaritons by irradiating a nanoslit structure J. Opt. Soc. Am. A (IF 1.9) Pub Date : 2024-02-06 Naoki Ichiji, Murat Yessenov, Kenneth L. Schepler, Ayman F. Abouraddy, and Atsushi Kubo
Space-time (ST) wave packets are propagation-invariant pulsed optical beams that travel freely in dielectrics at a tunable group velocity without diffraction or dispersion. Because ST wave packets maintain these characteristics even when only one transverse dimension is considered, they can realize surface-bound waves (e.g., surface plasmon polaritons at a metal-dielectric interface, which we call