Article
Physics, Multidisciplinary
Wu Di, Jiang Zi-Zhen, Yu Huan-Huan, Zhang Chen-Shuang, Lin Dan-Ying, Yu Bin, Qu Jun-Le
Summary: Quantitative phase imaging (QPI) combines phase imaging with optical microscopy technology to provide a marker-free, fast, non-destructive, and high-resolution imaging method for observing transparent biological samples. While spiral phase contrast microscopy (SPCM) has high stability and sensitivity, it requires complex image acquisition and reconstruction processes, as well as having low temporal resolution. A proposed quantitative phase imaging method based on a fractional spiral phase plate aims to improve the contrast and achieve quantitative reconstruction of weak phase objects in SPCM.
ACTA PHYSICA SINICA
(2021)
Article
Optics
Andrey V. Ustinov, Svetlana N. Khonina, Alexey P. Porfirev
Summary: This study focuses on shaping light fields with an inverse energy flux to guide nano- and microparticles towards a radiation source, using non-uniformly polarized laser beams. Results demonstrate the use of conventional and generalized spiral phase plates for creating light fields with an inverse energy flux, along with an analysis of the longitudinal and transverse components of the Poynting vector.
Article
Optics
Oana-Valeria Grigore, Alexandru Craciun
Summary: This study investigated the effect of illuminating a spiral phase plate (SPP) with a laser beam of a different wavelength, revealing the potential to determine the absolute value and sign of the SPP's topological charge using characteristic diffraction patterns. The results also suggest that this technique could be used for singularity manipulation and shaping the intensity distribution of vortex beams.
OPTICS AND LASER TECHNOLOGY
(2021)
Article
Engineering, Multidisciplinary
Ting Yang, Hongyin Shi, Zhijun Qiao
Summary: This study investigates the application of vortex beams carrying different orbital angular momentum (OAM) modes to synthetic aperture radar (SAR) systems. An enhanced SAR imaging method is proposed, which utilizes plane spiral OAM (PS-OAM) to form a pencil beam and eliminates the negative effects of traditional OAM. Numerical simulations demonstrate that the proposed method achieves high-precision focusing processing.
Article
Chemistry, Multidisciplinary
Hui Liu, Shiyou Wu, Meng Zhao, Chao Li, XiaoJun Liu, Guangyou Fang
Summary: This work introduces a terahertz spiral spatial filtering imaging method for enhancing THz image contrast. By utilizing Fourier transform and spiral phase modulation, the method effectively enhances THz image contrast and edge extraction, as validated through experiments with various simulated targets.
APPLIED SCIENCES-BASEL
(2021)
Article
Chemistry, Multidisciplinary
Muhammad Danial Shafqat, Nasir Mahmood, Muhammad Zubair, Muhammad Qasim Mehmood, Yehia Massoud
Summary: This study investigates the wavefront manipulation capability of all-dielectric metasurfaces using silicon nitride as a suitable material for the UV spectrum. By combining multiple phase distributions into a single device, perfect vortex beam generation is achieved. The results show that diffracted light from metasurfaces with different topological charges results in an annular intensity profile with the same ring radius.
Article
Optics
Yingqi Liao, Suhui Yang, Xuetong Lin, Yan Hao, Junwen Ji, Xinyu Liu, Zhen Xu
Summary: This study investigates the use of a spiral phase plate (SPP) for spatial coherence filtering in underwater lidar to reduce scattered light. The approach exploits the difference in spatial coherence between target-reflected light and scattered light to separate and filter out multiple-scattered clutters. Numerical simulation and experimental results demonstrate that this method significantly reduces the power of received scattered light, improves the temporal broadening and excessive delay of the returned pulse, and enhances ranging accuracy.
OPTICS AND LASER TECHNOLOGY
(2023)
Article
Optics
Yi Huang, Jun Chang, Chuhan Wu, Jiajing Cao, Yaoyao Hu, Jianping Zhang
Summary: We propose a computational imaging technique to expand the field of view of infrared thermometers. The contradiction between the field of view and focal length has been a major problem in infrared optical systems. Expensive and technically challenging large-area infrared detectors limit the performance of these systems. However, the increased demand for infrared optical systems during COVID-19 necessitates improving their performance and increasing the utilization of infrared detectors. This study presents a multi-channel frequency-domain compression imaging method based on point spread function (PSF) engineering that reduces the optical system's volume and improves energy efficiency.
Article
Optics
Lei Chen, Wenwen Gan, Linfei Chen, Haidan Mao
Summary: A new optical encryption technology based on spiral structured phase coherent superposition and vector beam generation system is proposed in this paper. The original image is scrambled and encoded into two phase plates, and the Stokes parameters of vector beam are recorded to complete the image encryption. The method shows good key sensitivity and resistance to occlusion attacks.
Article
Physics, Applied
A. H. Tavabi, P. Rosi, A. Roncaglia, E. Rotunno, M. Beleggia, P. -H. Lu, L. Belsito, G. Pozzi, S. Frabboni, P. Tiemeijer, R. E. Dunin-Borkowski, V. Grillo
Summary: This study reports the use of an electrostatic micro-electromechanical systems-based device to generate high-quality electron vortex beams with more than 1000 quanta of orbital angular momentum. Diffraction and off-axis electron holography experiments demonstrate that the diameter of the vortex in the diffraction plane increases linearly with OAM, providing a means to calibrate the angular momentum content of the vortex. The current limitation in achieving electron vortex beams with even larger values of OAM is the breakdown voltage of the device. Potential solutions to overcome this problem are discussed.
APPLIED PHYSICS LETTERS
(2022)
Article
Physics, Applied
Siyang Cheng, Yifan Liu, Panpan Yu, Yijing Wu, Ziqiang Wang, Yinmei Li, Lei Gong
Summary: Spiral phase contrast (SPC) imaging is an effective method for edge detection in biomedical applications. By combining partially coherent illumination and spiral phase filtering, this method can generate high-quality edge images with suppressed speckles.
APPLIED PHYSICS EXPRESS
(2022)
Article
Physics, Multidisciplinary
Qian Zhao, Shijie Tu, Qiannan Lei, Qingyang Yue, Chengshan Guo, Yangjian Cai
Summary: In this study, we propose a phase contrast imaging technique to detect the edges of invisible phase objects through complex media by overcoming scattering.
FRONTIERS OF PHYSICS
(2022)
Article
Acoustics
G. J. Chaplain, J. M. De Ponti
Summary: This paper presents the design of a device that converts guided elastic waves into non-axisymmetric flexural waves efficiently. By creating an elastic spiral phase pipe, the generation of non-axisymmetric waves is achieved. The design is verified through numerical simulations and experiments, confirming its effectiveness in solving the energy and information transmission problems.
JOURNAL OF SOUND AND VIBRATION
(2022)
Article
Radiology, Nuclear Medicine & Medical Imaging
Safa Oezdemir, Efe Ilicak, Jascha Zapp, Lothar R. Schad, Frank G. Zoellner
Summary: This study investigates spiral-based imaging as a fast and robust alternative for phase-based magnetic resonance electrical properties tomography (MREPT) techniques. The results show that spiral acquisitions have improved robustness against field inhomogeneity artifacts and shortened readout times.
MAGNETIC RESONANCE IN MEDICINE
(2023)
Article
Optics
Xiaoxuan Liu, Jinyun Zhou, Jiancai Xue, Ziming Meng
Summary: In this paper, we propose a new type of compound optical vortex (COV) generator that consists of an inner and outer spiral phase plate. The theoretical analysis and simulation results demonstrate the effectiveness of the design, and the unique characteristics of COV and potential applications are discussed.
Article
Engineering, Electrical & Electronic
Robert Orr, Vincent Fusco, Dmitry Zelenchuk, George Goussetis, Elena Saenz, Massimiliano Simeoni, Luca Salghetti Drioli
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2015)
Article
Engineering, Electrical & Electronic
Antonio Berenguer, Vincent Fusco, Dmitry E. Zelenchuk, Daniel Sanchez-Escuderos, Mariano Baquero-Escudero, Vicente E. Boria-Esbert
IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES
(2016)
Article
Engineering, Electrical & Electronic
Vincent Fusco, Dmitry Zelenchuk
IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS
(2017)
Article
Engineering, Electrical & Electronic
Vincent Fusco, Dmitry E. Zelenchuk, Neil B. Buchanan
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2014)
Article
Engineering, Electrical & Electronic
Muhammad Ali Babar Abbasi, Vincent Fusco, Dmitry E. Zelenchuk
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2018)
Article
Engineering, Electrical & Electronic
Yomna El-Saboni, Dmitry E. Zelenchuk, Gareth A. Conway, William G. Scanlon
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2020)
Article
Engineering, Electrical & Electronic
Sarah Clendinning, Robert Cahill, Dmitry Zelenchuk, Vincent Fusco
MICROWAVE AND OPTICAL TECHNOLOGY LETTERS
(2020)
Article
Computer Science, Information Systems
Camilla Karnfelt, Dmitry Zelenchuk, Maina Sinou, Francois Gallee, Paula Douglas
Article
Chemistry, Analytical
Dmitry Kozlov, Irina Munina, Pavel Turalchuk, Vitalii Kirillov, Alexey Shitvov, Dmitry Zelenchuk
Summary: A new implementation of a beam-steering transmitarray is proposed based on the tiled array architecture, enabling a wide range of beam steering and beam forming capabilities. Through hard-wired settings and phase modulation patterns, specific transmission characteristics and performance can be achieved. Testing of prototypes of tiled and single-panel transmitarrays show close performance to simulations and minimal impact from fabrication tolerances, indicating great potential for fifth-generation (5G) communication systems.
Article
Chemistry, Analytical
Stylianos D. Assimonis, Sandhya Chandravanshi, Okan Yurduseven, Dmitry Zelenchuk, Oleksandr Malyuskin, Muhammad Ali Babar Abbasi, Vincent Fusco, Simon L. Cotton
Summary: This paper introduces the application of resonant electric-based metamaterial element and its two-dimensional metasurface implementation in various emerging wireless applications, showcasing its potential for applications such as absorption, transmission, and reflection manipulation. The study demonstrates that the resonant electric-synthesized metasurface concept has significant potential for high fidelity absorption, transmission, and reflection characteristics in the microwave frequency spectrum.
Article
Computer Science, Information Systems
Dmitry Zelenchuk, Vitalii Kirillov, Camilla Karnfelt, Francois Gallee, Irina Munina
Summary: In this study, a metamaterial-based LTCC compressed Luneburg lens was designed, manufactured and measured for wireless communication networks. The lens was designed at 60 GHz and utilized the unlicensed mm-wave spectrum for short-range high-capacity communication. The transformation optics method was used to compress the Luneburg lens antenna and maintain a low-profile structure. The manufacturing process and measurement results of the lens were discussed, showing a size reduction of 63.6% and a peak antenna gain of 16 dBi at 60 GHz.
Article
Engineering, Electrical & Electronic
N. McGuigan, G. Conway, R. Cahill, D. Zelenchuk, S. Zabri
ELECTRONICS LETTERS
(2017)
Proceedings Paper
Engineering, Electrical & Electronic
Dmitry Zelenchuk, Vincent Fusco
2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP)
(2016)
Proceedings Paper
Engineering, Electrical & Electronic
Dmitry Zelenchuk, Vincent Fusco, James Breslin, Mike Keaveney
2015 45TH EUROPEAN MICROWAVE CONFERENCE (EUMC)
(2015)
Proceedings Paper
Engineering, Electrical & Electronic
Dmitry Zelenchuk, Vincent Fusco, James Breslin, Mike Keaveney
2015 45TH EUROPEAN MICROWAVE CONFERENCE (EUMC)
(2015)
