Results 11 to 20 of about 52,858 (287)
Enhancing laser speckle reduction by decreasing the pitch of a chiral nematic liquid crystal diffuser [PDF]
Scientific Reports, 2021 The artefact known as speckle can plague numerous imaging applications where the narrow linewidth of laser light is required, which includes laser projection and medical imaging.
David J. Hansford +3 more
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Upper limit for angular compounding speckle reduction [PDF]
Applied Physics Letters, 2019 Angular compounding is a technique for reducing speckle noise in optical coherence tomography that is claimed to significantly improve the signal-to-noise ratio (SNR) of images without impairing their spatial resolution. Here, we examine how focal point movements caused by optical aberrations in an angular compounding system may produce unintended ...
Yonatan Winetraub +4 more
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Physical pupil manipulation for speckle reduction in digital holographic microscopy [PDF]
Heliyon, 2021 The reduction of speckle noise by physically changing the pupil of the imaging system, as first envisioned in optical holography, is experimentally applied to a digital holographic microscope (DHM).
Carlos Buitrago-Duque +1 more
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Beamforming and Speckle Reduction Using Neural Networks [PDF]
IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 2019 With traditional beamforming methods, ultrasound B-mode images contain speckle noise caused by the random interference of subresolution scatterers. In this paper, we present a framework for using neural networks to beamform ultrasound channel signals into speckle-reduced B-mode images.
Dongwoon Hyun +3 more
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Speckle reduction using phase plate array and lens array
Opto-Electronic Advances, 2020 In this paper, a solution for speckle reduction using phase plate array (PPA) and lens array (LA) in a motionless way is proposed. The specially designed PPA is composed of sub-phase plates, which are constituted by phase patterns formed by Hadamard sub ...
Xiaohui Ma +4 more
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Speckle reduction in double-pass retinal images [PDF]
Scientific Reports, 2019 AbstractThe double pass (DP) technique quantifies the optical quality of the eye by measuring its point spread function. The low reflectivity of the retina requires the use of a high-brightness, point-like illumination source, and thus, DP systems use laser diodes (LDs).
Halpaap Halpaap, Herbert Donatus +3 more
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Speckle reduction in double-pass retinal images using variable-focus lenses [PDF]
Journal of the European Optical Society-Rapid Publications, 2015 Speckle arises in double-pass images when coherent light is scattered by the retina. Since this noise degrades the images that are used to characterize the eye, there is special attention in reducing speckle when working with instruments based on retina ...
García-Guerra C. E. +3 more
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Speckle reduction with adaptive stack filters [PDF]
Pattern Recognition Letters, 2014 Accepted for publication on Pattern Recognition Letters.
Buemi, Maria Elena +2 more
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Speckle Reduction Using Stochastic Distances [PDF]
, 2012 This paper presents a new approach for filter design based on stochastic distances and tests between distributions. A window is defined around each pixel, samples are compared and only those which pass a goodness-of-fit test are used to compute the filtered value.
Torres, Leonardo +2 more
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IEEE Photonics Journal, 2017 Sequential speckle reduction methods demand the usage of fast modulators due to the short integration period of human eyes. Here, a nonsequential speckle reduction method by splitting one laser beam with short coherence length into uncorrelated laser ...
Zhaomin Tong +3 more
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