Application of Phase-Reversal Fresnel Zone Plates for High-Resolution Robotic Ultrasonic Non-Destructive Evaluation [PDF]
Sensors, 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
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Dual-band and dual-polarized reflective Fresnel zone plate design based on Fractal shape [PDF]
Scientific 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
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An Annular Fresnel Zone Plate without Central Spots Fabricated by Femtosecond Laser Direct Writing [PDF]
Micromachines, 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
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Silicon Fresnel Zone Plate Metalens with Subwavelength Gratings [PDF]
Sensors, 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
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Zone-Shrinking Fresnel Zone Travel-Time Tomography for Sound Speed Reconstruction in Breast USCT [PDF]
Sensors, 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
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Fabrication of Terahertz Fresnel Zone Plates via Ultraprecision Mechanical Processing [PDF]
MicromachinesThis study proposes a new fabrication process for terahertz Fresnel zone plates on high-resistivity silicon substrates. It involves ion implantation surface modification, ultra-precision diamond turning, and magnetron sputtering, followed by polishing ...
Meng Chen, Jinshi Wang, Fengzhou Fang
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Transient Analysis of Fresnel Zone Plates for Ultrasound Focusing Applications [PDF]
Sensors, 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
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High efficiency and scalable fabrication of fresnel zone plates using holographic femtosecond pulses [PDF]
Nanophotonics, 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
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Numerical Fresnel models of Fresnel zone plates for plane wave at angle of incidence [PDF]
Scientific ReportsDiffractive optical elements (DOEs) are increasingly used in electro-optical systems due to their design flexibility, which offers advantages over refractive optics.
Ahmet Ünal
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Bifocal Ultrasound Focusing Using Bi-Fresnel Zone Plate Lenses [PDF]
Sensors, 2020 In this work, we present a bifocal Fresnel zone plate (BiFZP) capable of generating focusing profiles with two different foci. The performance of the BiFZP is demonstrated in the ultrasound domain, with a very good agreement between the experimental ...
Sergio Pérez-López +5 more
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