Results 31 to 40 of about 2,554 (206)
Nonparaxial abruptly autofocusing beams [PDF]
Optics Letters, 2016 5 pages, 8 figures.
Raluca-Sorina Penciu +2 more
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Properties of off-axis caustics of autofocusing chirp beams
Компьютерная оптика, 2020 Autofocusing properties of chirp beams with an arbitrary power-law dependence on the radius are studied theoretically and numerically. Two- and three-parameter chirp beams are considered, the parameter variations of which make it possible to effectively ...
A.V. Ustinov, S.N. Khonina
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Learning-based nonparametric autofocusing for digital holography [PDF]
, 2018 In digital holography, it is crucial to extract the object distance from a hologram in order to reconstruct its amplitude and phase. This is known as autofocusing, which is conventionally solved by first reconstructing a stack of images, and then the ...
Edmund Y. Lam +5 more
core +1 more source
IEEE Access, 2019 The spaceborne synthetic aperture radar (SAR) system working at P-band, is vulnerable to the ionospheric effect. The ionospheric scintillation will introduce random phase fluctuations into the SAR signal and deteriorate the imaging performance.
Lei Yu +4 more
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Polarimetric ISAR autofocusing
IET Signal Processing, 2008 Interest in polarimetric inverse synthetic aperture radar (ISAR) systems has been growing because of their capability to provide extra information about the imaged target compared with single polarisation ISAR systems. Target classification and recognition can be improved by exploiting full polarisation ISAR images.
MARTORELLA, MARCO +4 more
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Autofocusing Algorithm for Pixel-Super-Resolved Lensfree On-Chip Microscopy
Frontiers in Physics, 2021 In recent years, lensfree on-chip microscopy has developed into a promising and powerful computational optical microscopy technique that allows for wide-field, high-throughput microscopic imaging without using any lenses.
Yumin Wu +19 more
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Laguerre-Gaussian Beams with an Increased Dark Area and Autofocusing
Photonics, 2022 We introduce and investigate a novel Laguerre-Gaussian (LG) beam, different from the conventional modal LG beams, which conserve the transverse intensity structure (up to scale) on propagation.
Victor V. Kotlyar +3 more
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International Journal of Aerospace Engineering, 2016 In order to realize the autofocusing in aerial camera, an autofocusing system is established and its characteristics such as working principle and optical-mechanical structure and focus evaluation function are investigated.
Zhichao Chen, Tao Zhang
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Robust autofocusing for scanning electron microscopy based on a dual deep learning network
Scientific Reports, 2021 Scanning electron microscopy (SEM) is a high-resolution imaging technique with subnanometer spatial resolution that is widely used in materials science, basic science, and nanofabrication.
Woojin Lee +5 more
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Abruptly autofocusing vortex beams
Optics Express, 2012 We generate abruptly autofocusing beams that produce vortices at the focus. We give explicit equations for the phase-only Fourier masks that generate these beams including explanations for controlling the focal distance and numerical aperture. We show experimental results for the focal distance, the vortex pattern and show that the diameter of the ...
Jeffrey A, Davis +2 more
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