Results 71 to 80 of about 3,110,122 (363)
Deep-learned speckle pattern and its application to ghost imaging [PDF]
arXiv, 2021 In this paper, we present a method for speckle pattern design using deep learning. The speckle patterns possess unique features after experiencing convolutions in Speckle-Net, our well-designed framework for speckle pattern generation. We then apply our method to the computational ghost imaging system.
arxiv
Diffuse Speckle Contrast Analysis (DSCA) for Deep Tissue Blood Flow Monitoring
Advanced Biomedical Engineering, 2020 Assessing blood ow, as well as blood volume and oxygen saturation, is of utmost importance for health monitoring. Assessing microcirculation, as opposed to macrocirculation, is especially important for assessing the local tissue viability.
Kijoon Lee
semanticscholar +1 more source
Synthetic exposure: a simplified and accurate acquisition scheme for multiple exposure speckle imaging of blood flow [PDF]
arXiv, 2021 Speckle contrast imaging is an established technique to obtain relative blood maps over wide field of views. Currently, its most accurate implementation relies on the acquisition of raw speckle images at different exposure times but requires modulation of a laser pulse in duration and intensity and precise synchronization with camera.
arxiv
Multi-frame speckle reduction in OCT using supercontinuum pumped by noise-like pulses [PDF]
Journal of Innovative Optical Health Sciences, 2019 In most coherent imaging modality, speckle noise is a major cause that blurs the boundary of tissues and degrades the image contrast. By utilizing the unique properties of supercontinuum (SC) generated by noise-like pulses (NLPs) and a simple multi-frame
Chengming Wang +10 more
doaj +1 more source
Singularities in Speckled Speckle [PDF]
, 2007 Speckle patterns produced by random optical fields with two (or more) widely different correlation lengths exhibit speckle spots that are themselves highly speckled. Using computer simulations and analytic theory we present results for the point singularities of speckled speckle fields: optical vortices in scalar (one polarization component) fields; C ...
arxiv +1 more source
Exploration of movement artefacts in handheld laser speckle contrast perfusion imaging.
Biomedical Optics Express, 2020 Functional performance of handheld laser speckle contrast imaging (LSCI) is compromised by movement artefacts. Here we quantify the movements of a handheld LSCI system employing electromagnetic (EM) tracking and measure the applied translational, tilt ...
Ata Chizari +4 more
semanticscholar +1 more source
Correction of overexposure in laser speckle contrast imaging
Optics Express, 2022 Laser speckle contrast imaging (LSCI) is a method to visualize and quantify tissue perfusion and blood flow. A common flaw in LSCI variants is their sensitivity to the optical setup parameters and that they operate well only on statistics of undistorted laser speckle patterns.
Péter Földesy +3 more
openaire +3 more sources
Study on Speckle Noise Reduction in Laser Projection Displays
PhotonicsLaser speckle has a negative effect on laser projectors, so reducing laser speckle is crucial for the development of laser projector displays. We primarily focus on studying the laser speckle contrast of laser projector displays and the mechanism for ...
Hongyou Zhang +3 more
doaj +1 more source
Speckle Temporal Stability in eXtreme Adaptive Optics Coronagraphic Images [PDF]
, 2012 The major noise source limiting high-contrast imaging is due to the presence of quasi-static speckles. Speckle noise originates from wavefront errors caused by various independent sources, and it evolves on different timescales pending to their nature.
arxiv +1 more source
Convolutional neural network-based single-shot speckle tracking for x-ray phase-contrast imaging [PDF]
arXiv, 2023 X-ray phase-contrast imaging offers enhanced sensitivity for weakly-attenuating materials, such as breast and brain tissue, but has yet to be widely implemented clinically due to high coherence requirements and expensive x-ray optics. Speckle-based phase contrast imaging has been proposed as an affordable and simple alternative; however, obtaining high-
arxiv