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Application of Phase-Reversal Fresnel Zone Plates for High-Resolution Robotic Ultrasonic Non-Destructive Evaluation [PDF]

open access: goldSensors, 2021
Nowadays the development of automated inspection systems based on six degrees of freedom robotic manipulators is a highly relevant topic in ultrasonic non-destructive testing. One of the issues associated with such development is the problem of acquiring
Dmitry O. Dolmatov   +4 more
doaj   +4 more sources

Polarization-Independent Metasurface Lens Based on Binary Phase Fresnel Zone Plate [PDF]

open access: goldNanomaterials, 2020
Based on the binary phase Fresnel zone plate (FZP), a polarization-independent metasurface lens that is able to focus incident light with any polarization state, including circular, linear, and elliptical polarizations, has been proposed and investigated.
Xing Li, Jing Tang, Jonathan Baine
doaj   +4 more sources

Dual-band and dual-polarized reflective Fresnel zone plate design based on Fractal shape [PDF]

open access: yesScientific Reports, 2023
In this study, a dual-polarized and dual band reflective Fresnel zone plate with reconfigurable beam is proposed on the basis of fractal frequency selective surface (FSS) unit with nearly 360° phase tunability.
Lusong Wei   +6 more
doaj   +2 more sources

An Annular Fresnel Zone Plate without Central Spots Fabricated by Femtosecond Laser Direct Writing [PDF]

open access: yesMicromachines, 2022
In recent years, micro-annular beams have been widely used, which has expanded the possibilities for laser processing. However, the current method of generating an annular beam still has shortcomings, such as spot energy at the center of the produced ...
Xiaoyan Sun, Fang Zhou, Lian Duan
doaj   +2 more sources

Silicon Fresnel Zone Plate Metalens with Subwavelength Gratings [PDF]

open access: yesSensors, 2023
Metalenses are planar optical components that have demonstrated immense potential for integrated optics. In particular, they are capable of high-efficiency subwavelength focusing without the bulkiness of traditional lenses.
William Fraser, Winnie N. Ye
doaj   +2 more sources

Zone-Shrinking Fresnel Zone Travel-Time Tomography for Sound Speed Reconstruction in Breast USCT [PDF]

open access: yesSensors, 2020
Many studies have been carried out on ultrasound computed tomography (USCT) for its potential application in breast imaging. The sound speed (SS) image modality in USCT can help doctors diagnose the breast cancer, as the tumor usually has a higher sound ...
Xiaoyue Fang   +8 more
doaj   +2 more sources

Transient Analysis of Fresnel Zone Plates for Ultrasound Focusing Applications [PDF]

open access: yesSensors, 2020
Fresnel Zone Plates are planar lenses that can be used to focus ultrasound beams. This kind of acoustic lenses can play a key role in the resolution of ultrasonic NDT systems.
Sergio Pérez-López   +4 more
doaj   +2 more sources

High-Resolution Imaging: An Approach by Compensating Absorption and Dispersion in Prestack Time Migration With Effective Q Estimation and Fresnel Zone Identification Based on Deep Learning [PDF]

open access: goldFrontiers in Earth Science, 2022
We have developed a migration scheme that can compensate absorption and dispersion with effective Q estimation and Fresnel zone identification based on deep learning.
Jizhong Wu   +4 more
doaj   +2 more sources

High efficiency and scalable fabrication of fresnel zone plates using holographic femtosecond pulses [PDF]

open access: yesNanophotonics, 2022
To meet the growing demand for photonic integration and device miniaturization, planar diffractive Fresnel zone plates (FZPs) are widely applied in integrated optical systems.
Wang Zhipeng   +8 more
doaj   +2 more sources

Numerical Fresnel models of Fresnel zone plates for plane wave at angle of incidence [PDF]

open access: yesScientific Reports
Diffractive optical elements (DOEs) are increasingly used in electro-optical systems due to their design flexibility, which offers advantages over refractive optics.
Ahmet Ünal
doaj   +2 more sources

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