High-performance etching of multilevel phase-type Fresnel zone plates with large apertures
Sign Up to like & getrecommendations! Published in 2018 at "Optics Communications"
DOI: 10.1016/j.optcom.2017.09.006
Abstract: Abstract To ensure the etching depth uniformity of large-aperture Fresnel zone plates (FZPs) with controllable depths, a combination of a point source ion beam with a dwell-time algorithm has been proposed. According to the obtained… read more here.
Keywords: large apertures; fresnel zone; zone plates; etching depth ... See more keywords
Nonlinear Metasurface Fresnel Zone Plates for Terahertz Generation and Manipulation
Sign Up to like & getrecommendations! Published in 2019 at "Nano Letters"
DOI: 10.1021/acs.nanolett.9b01970
Abstract: We introduce a nanoengineered nonlinear metasurface based optical element that acts as an emitting Fresnel zone plate of terahertz (THz) waves. We show that the nonlinear zone plate generates broadband THz radiation and focuses each… read more here.
Keywords: zone; fresnel zone; metasurface; zone plate ... See more keywords
Sub-wavelength lateral detection of tissue-approximating masses using an ultrasonic metamaterial lens
Sign Up to like & getrecommendations! Published in 2020 at "Nature Communications"
DOI: 10.1038/s41467-020-19591-2
Abstract: Practically applied techniques for ultrasonic biomedical imaging employ delay-and-sum (DAS) beamforming which can resolve two objects down to 2.1λ within the acoustic Fresnel zone. Here, we demonstrate a phononic metamaterial lens (ML) for detection of… read more here.
Keywords: detection; tissue approximating; approximating masses; tissue ... See more keywords
Graphene nanoribbon based plasmonic Fresnel zone plate lenses
Sign Up to like & getrecommendations! Published in 2017 at "RSC Advances"
DOI: 10.1039/c6ra27942b
Abstract: A graphene-based metamaterial lens is theoretically proposed by combining plasmonic nanoribbons with Fresnel Zone Plate (FZP) architecture to realize wavelength-selective and tunable lensing. The plasmonic FZP lens shows higher focal intensity and efficiency compared to… read more here.
Keywords: effect; fresnel zone; plate lenses; zone plate ... See more keywords
Double-Stage DMAS With Fresnel Zone Filtering in Guided Waves Damage Imaging
Sign Up to like & getrecommendations! Published in 2022 at "IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control"
DOI: 10.1109/tuffc.2022.3162323
Abstract: Digital beamforming methods in plate-like structures are widely exploited for Lamb waves-based damage imaging. Among them, the delay and sum (DAS) imaging technique is the most popular thanks to its low-computational cost and ease of… read more here.
Keywords: dmas; double stage; fresnel zone; damage ... See more keywords
Fresnel zone plate fabricated using a polyvinyl chloride gel
Sign Up to like & getrecommendations! Published in 2018 at "Optical Engineering"
DOI: 10.1117/1.oe.57.11.117101
Abstract: Abstract. Based on creep-induced deformation of a polyvinyl chloride (PVC) gel in an electric field, a Fresnel zone plate (FZP) is fabricated. The employed electrode is constructed with a series of concentric zones, and the… read more here.
Keywords: pvc; fresnel zone; polyvinyl chloride; gel ... See more keywords
Aberration correction of Fresnel zone lenses telescope based on adaptive optics system
Sign Up to like & getrecommendations! Published in 2018 at "Optical Engineering"
DOI: 10.1117/1.oe.57.6.063107
Abstract: Abstract. Fresnel zone lens (FZL) telescope is attracting increasing attention owing to its small volume and light weight. However, depending on the fabrication method of FZL, the linewidth and etch depth of FZL may deviate… read more here.
Keywords: system; correction; optics; fresnel zone ... See more keywords
Synthesis and analysis of a planar waveguide array with two-dimensional frequency scanning focused in the Fresnel zone
Sign Up to like & getrecommendations! Published in 2017 at "Journal of Communications Technology and Electronics"
DOI: 10.1134/s1064226917090030
Abstract: A 2D array of radiators with raster frequency scanning focused in the Fresnel zone is presented. The problem of determining the radiator positions for field focusing at a finite distance from the array plane is… read more here.
Keywords: focused fresnel; array; frequency scanning; scanning focused ... See more keywords
Fresnel zone plate development for x-ray radiography of hydrodynamic instabilities at the National Ignition Facility.
Sign Up to like & getrecommendations! Published in 2020 at "Applied optics"
DOI: 10.1364/ao.408569
Abstract: The study of Rayleigh-Taylor (RT) and Richtmyer-Meshkov (RM) instabilities in a planar geometry at high energy densities at the National Ignition Facility (NIF) requires high spatial resolution imaging. We demonstrate the potential of Fresnel zone… read more here.
Keywords: resolution; facility; fresnel zone; ignition facility ... See more keywords
Investigation of axial and transverse focal spot sizes of Fresnel zone plates.
Sign Up to like & getrecommendations! Published in 2017 at "Applied optics"
DOI: 10.1364/ao.56.003725
Abstract: An axial spot size formula is given for a standard binary Fresnel zone plate (FZP) illuminated with a linearly polarized beam. The axial spot size, characterized by the full width at half-maximum (FWHM), can be… read more here.
Keywords: transverse focal; spot; axial transverse; fresnel zone ... See more keywords
Autofocusing of Fresnel zone aperture lensless imaging for QR code recognition.
Sign Up to like & getrecommendations! Published in 2023 at "Optics express"
DOI: 10.1364/oe.489157
Abstract: Fresnel zone aperture (FZA) lensless imaging encodes the incident light into a hologram-like pattern, so that the scene image can be numerically focused at a long imaging range by the back propagation method. However, the… read more here.
Keywords: recognition; fresnel zone; zone aperture; lensless ... See more keywords