Results 21 to 30 of about 5,516 (216)
Speckle pattern formation in spatially limited optical systems
Semiconductor Physics, Quantum Electronics & Optoelectronics, 2016 The dependences of statistical parameters inherent to speckle patterns on the object roughness and aperture size have been investigated. The experimental results that confirm theoretical dependence quality within the limits of errors were obtained.
M.M. Kotov
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Opto-thermoelectric speckle tweezers
Nanophotonics, 2020 Opto-thermoelectric tweezers present a new paradigm for optical trapping and manipulation of particles using low-power and simple optics. New real-life applications of opto-thermoelectric tweezers in areas such as biophysics, microfluidics, and ...
Kotnala Abhay +2 more
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Speckle filtering of Synthetic Aperture Radar images using filters with object-size-adapted windows
International Journal of Digital Earth, 2018 Speckle degrades the radiometric quality of a Synthetic Aperture Radar (SAR) image. Previous methods for speckle reduction have used a fixed-size window for filtering the entire image.
Sahel Mahdavi +4 more
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Review of speckle on high resolution synthetic aperture radar imagery
Nantong Daxue xuebao. Ziran kexue ban, 2022 Understanding the speckle mechanism and modelling the physical representation is the theoretical basis for understanding synthetic aperture radar(SAR) images.
XU Zhihuo; LI Hengchao
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Single-Shot Structured Light Sensor for 3D Dense and Dynamic Reconstruction
Sensors, 2020 Structured light (SL) has a trade-off between acquisition time and spatial resolution. Temporally coded SL can produce a 3D reconstruction with high density, yet it is not applicable to dynamic reconstruction.
Feifei Gu, Zhan Song, Zilong Zhao
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Demonstration of a Speckle Based Sensing with Pulse-Doppler Radar for Vibration Detection
Sensors, 2018 In previous works, an optical technique for extraction and separation of remote static vibrations has been demonstrated. In this paper, we will describe an approach in which RF speckle movement is used to extract remote vibrations of a static target. The
Nisan Ozana +6 more
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SAR Image Despeckle With CNN Using a Novel Logarithmic Discrete Cosine Transform-Based Loss
IEEE Journal of Selected Topics in Applied Earth Observations and Remote SensingThe coherent nature of imaging in synthetic aperture radar (SAR) inevitably gives rise to speckle noise, a challenge exacerbated by the constrained bandwidth and limited look angles.
Ammar Saleem +2 more
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Optical Energy Variability Induced by Speckle: The Cases of MERLIN and CHARM-F IPDA Lidar
Atmosphere, 2019 In the context of the FrenchGerman space lidar mission MERLIN (MEthane Remote LIdar missioN) dedicated to the determination of the atmospheric methane content, an end-to-end mission simulator is being developed.
Vincent Cassé +4 more
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Speckle tracking approaches in speckle sensing [PDF]
SPIE Proceedings, 2017 This paper reports some initial investigations into the application of feature tracking algorithms as an alternative data processing method for speckle correlation sensors capable of determining both the speckle pattern translation and rotation. The accuracy of translation measurements using the feature tracking approach was found to be similar to that
Charrett, Thomas O. H. +2 more
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Photon-Counting Security Tagging and Verification Using Optically Encoded QR Codes
IEEE Photonics Journal, 2014 We propose an optical security method for object authentication using photon-counting encryption implemented with phase encoded QR codes. By combining the full phase double-random-phase encryption with photon-counting imaging method and applying an ...
A. Markman, B. Javidi, M. Tehranipoor
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