Structured illumination,a wide-field imaging approach used in microscopy to enhance image resolution beyond the system's diffraction limits,is a well-studied technique that has gained significant traction over the...Structured illumination,a wide-field imaging approach used in microscopy to enhance image resolution beyond the system's diffraction limits,is a well-studied technique that has gained significant traction over the last two decades.However,when translated to endoscopic systems,severe deformations of illumination patterns occur due to the large depth of field(DOF)and the 3D nature of the targets,introducing significant implementation challenges.Hence,this study explores a speckle-based system that best suits endoscopic practices to enhance image resolution by using random illumination patterns.The study presents a prototypic model of an endoscopic add-on,its design,and fabrication facilitated by using the speckle structured illumination endoscopic(SSIE)system.The imaging results of the SSIE are explained on a colon phantom model at different imaging planes with a wide field of view(FOV)and DOF.The obtained imaging metrics are elucidated and compared with state-of-the-art(SOA)high-resolution endoscopic techniques.Moreover,the potential for a clinical translation of the prototypic SSIE model is also explored in this work.The incorporation of the add-on and its subsequent results on the colon phantom model could potentially pave the way for its successful integration and use in futuristic clinical endoscopic trials.展开更多
Laser speckle contrast imaging(LSCI)is a noninvasive,label-free technique that allows real-time investigation of the microcirculation situation of biological tissue.High-quality microvascular segmentation is critical ...Laser speckle contrast imaging(LSCI)is a noninvasive,label-free technique that allows real-time investigation of the microcirculation situation of biological tissue.High-quality microvascular segmentation is critical for analyzing and evaluating vascular morphology and blood flow dynamics.However,achieving high-quality vessel segmentation has always been a challenge due to the cost and complexity of label data acquisition and the irregular vascular morphology.In addition,supervised learning methods heavily rely on high-quality labels for accurate segmentation results,which often necessitate extensive labeling efforts.Here,we propose a novel approach LSWDP for high-performance real-time vessel segmentation that utilizes low-quality pseudo-labels for nonmatched training without relying on a substantial number of intricate labels and image pairing.Furthermore,we demonstrate that our method is more robust and effective in mitigating performance degradation than traditional segmentation approaches on diverse style data sets,even when confronted with unfamiliar data.Importantly,the dice similarity coefficient exceeded 85%in a rat experiment.Our study has the potential to efficiently segment and evaluate blood vessels in both normal and disease situations.This would greatly benefit future research in life and medicine.展开更多
Retrieving high-fidelity images from optical speckles remains challenging,especially when the information in speckles is severely insufficient.To address classification through scattering media under such constraints,...Retrieving high-fidelity images from optical speckles remains challenging,especially when the information in speckles is severely insufficient.To address classification through scattering media under such constraints,we propose Speckle Transformer,a vision-transformer-based model that directly classifies objects using raw speckle patterns without intermediate image retrieval.By leveraging inherent features within speckles to extract discriminative features,our approach achieves nearly 90%accuracy for classifying speckles encoded with different images,outperforming traditional retrieval-classification pipelines by up to five times,even with extreme information sparsity(i.e.,1/1024 speckle regions of interest).In addition,we quantify speckle information capacity via information entropy analysis,demonstrating that classification accuracy correlates strongly with the information entropy of speckle autocorrelation.We not only overcome limitations of conventional methods but also establish a paradigm for real-time classification in scattering environments with constrained data.展开更多
This paper discusses and studies the composition and characteristics of biospeckle on the surface of bone tissues.We used a laser speckle device to capture biospeckle patterns from fresh pig bone tissue.Traditional sp...This paper discusses and studies the composition and characteristics of biospeckle on the surface of bone tissues.We used a laser speckle device to capture biospeckle patterns from fresh pig bone tissue.Traditional speckle activity metrics were used to measure the speckle activity of ex vivo bone tissue over time.Both Gaussian and Lorentzian correlation functions were used to char-acterize the ordered and disordered motion of the bone surface,together with volume scattering,to construct the model.Using the established mathematical model of the spatio-temporal evo-lution of the biospeckle pattern,it is possible to account for the presence of volume scattering from the biospeckle of bones,quantify the ordered or disordered motions in the biological speckle activity at the current time,and assess the ability of laser speckle correlation technique to determine biological activity.展开更多
When a surface is illuminated by laser,the field of diffusing reflective light can be described by Fresnel-Kirchhoff integration in the region of Fresnel.If the correlation,before and after the change of intensity fie...When a surface is illuminated by laser,the field of diffusing reflective light can be described by Fresnel-Kirchhoff integration in the region of Fresnel.If the correlation,before and after the change of intensity field,is analysed by statistical method,three governing equations for variations of intensity field and speckle movement formulas can be obtained.In these equations,the surface motion,deformation and wavelength change are all considered to cause the speckle movement.展开更多
The influence of ischemia-reperfusion(I/R)action on pancreatic blood flow(PBF)and the development of acute pancreatitis(AP)in laboratory rats is evaluated in vivo by using the laser speckle contrast imaging(LSCI).Addi...The influence of ischemia-reperfusion(I/R)action on pancreatic blood flow(PBF)and the development of acute pancreatitis(AP)in laboratory rats is evaluated in vivo by using the laser speckle contrast imaging(LSCI).Additionally,the optical properties in norm and under condition of AP in rats were assessed using a modied integrating sphere spectrometer and inverse Monte Carlo(IMC)software.The results of the experimental study of microcirculation of the pancreas in 82 rats in the ischemic model are presented.The data obtained conrm the fact that local ischemia and changes in the blood°ow velocity of the main vessels cause and provoke acute pancreatitis.展开更多
Surface roughness is commonly used to characterize material microstructure during processing,and accurate measurement of surface roughness is the premise and foundation of machining.Therefore,online non-destructive me...Surface roughness is commonly used to characterize material microstructure during processing,and accurate measurement of surface roughness is the premise and foundation of machining.Therefore,online non-destructive measurement of surface roughness based on the laser speckle method has become a hot issue in recent research.The improvements in surface roughness measurements based on the laser speckle method are systematically reviewed.Theory of speckle formation is introduced.The statistical properties of the speckle patterns including first-order statistical properties and second-order statistical properties are directly related to surface roughness.Surface roughness measurements based on the laser speckle method are roughly divided into the speckle contrast method,speckle correlation method,and fractal method.The three methods are described in detail,and an extensive comparison among all the methods is presented.The recent progresses and application of surface roughness measurements are reviewed.Finally,surface roughness measurements based on the laser speckle method are prospected and summarized.展开更多
The quality of ultrasound scanning images is usually damaged by speckle noise.This paper proposes a method based on local statistics extracted from a histogram to reduce ultrasound speckle through a region growing alg...The quality of ultrasound scanning images is usually damaged by speckle noise.This paper proposes a method based on local statistics extracted from a histogram to reduce ultrasound speckle through a region growing algorithm.Unlike single statistical moment-based speckle reduction algorithms,this method adaptively smooths the speckle regions while preserving the margin and tissue structure to achieve high detectability.The criterion of a speckle region is defined by the similarity value obtained by matching the histogram of the current processing window and the reference window derived from the speckle region in advance.Then,according to the similarity value and tissue characteristics,the entire image is divided into several levels of speckle-content regions,and adaptive smoothing is performed based on these classification characteristics and the corresponding window size determined by the proposed region growing technique.Tests conducted from phantoms and in vivo images have shown very promising results after a quantitative and qualitative comparison with existing work.展开更多
[Objective] The research aimed at investigating the application of laser speckle technology in agricultural products detection.[Method] This article described the basic principle of the laser speckle technology,provid...[Objective] The research aimed at investigating the application of laser speckle technology in agricultural products detection.[Method] This article described the basic principle of the laser speckle technology,provided a review of application development of the laser speckle technology in agricultural products detection,analyzed the problems in agriculture products detection using laser speckle technology and described the prospects of laser speckle technology in agricultural products detection.[Result] The laser speckle technology is a non-destructive detection technology for quality determination of agricultural products,which can be used to classify the agricultural products reasonably according to the quality of agricultural products.[Conclusion] The article provided reference and consult for laser speckle detection technology research.展开更多
Two speckle patterns are recorded using a video cameracorresponding to undisplaced and displaced states into the memory ofa computer. After one pattern is added to another, the displacementof the measured points can b...Two speckle patterns are recorded using a video cameracorresponding to undisplaced and displaced states into the memory ofa computer. After one pattern is added to another, the displacementof the measured points can be calculated by using the Fouriertransform. The expression of displacement field is deduced fornon-uniform displacement, and as an example, a rotatanle disc istested for illustration. The re- sults prove that the present methodis promising.展开更多
One of the advantages of laser speckle is detecting microvascular through image processing. This paper proposes a new image processing method for laser speckle, adaptive window method that adaptively processes laser s...One of the advantages of laser speckle is detecting microvascular through image processing. This paper proposes a new image processing method for laser speckle, adaptive window method that adaptively processes laser speckle images in the space. Disadvantage of conventional fixed window method is that it uses the same window size regardless of target areas. Inherently laser speckle contains undesired noise. Thus a large window is helpful for removing the noise, but it results in low resolution of image. Otherwise a small window may detect micro vascular but it has limits in noise removal. To overcome this trade-off, the concept of adaptive window method is newly introduced to conventional laser speckle image analysis. In addition, the modified adaptive window method applied to other selection images. We have compared conventional Laser Speckle Contrast Analysis （LASCA） and its variants with the proposed method in terms of image quality and processing complexity, Moreover compared the result of the accompamed changing sdection images have also been compared.展开更多
Speckles in images formed by a laser beam are interference noise arising due to coherent nature of laser radiation. As the number of projection systems using laser light sources increases, new methods and devices appe...Speckles in images formed by a laser beam are interference noise arising due to coherent nature of laser radiation. As the number of projection systems using laser light sources increases, new methods and devices appear for reducing the contrast of speckle-noise and thereby suppressing it. Taking into account the long-standing nature of the problem and the continuing relevance of its solution, this review discusses modern practical methods and devices—despecklers, used to reduce the speckle contrast and to achieve high quality of projected images. The review discusses the nature of the speckles appearance, considers their statistical properties, and describes the measurement of the speckle contrast. The requirements for despecklers are considered, the most important of which are speckle suppression efficiency, simplicity of design and compactness, low power consumption and low optical loss. The characteristics of different types of despecklers, including diffusers, devices based on electroactive polymers, optical waveguides, colloidal solutions and liquid crystals, as well as orthogonal phase matrices and diffraction gratings proposed as despeckers, are examined in detail. It is shown that despecklers with decorrelation of the phase front based on the mirror deformation and optical fiber have less light losses. Electro-optical-liquid crystal despecklers do not have mechanically deformable or moving elements that reduce the reliability and durability of operation, and are more compact and simple in design. A comparative table of characteristics of the most effective despecklers in which the speckle contrast is reduced to ten percent or less, with an indication of their advantages and disadvantages, is given.展开更多
文摘Structured illumination,a wide-field imaging approach used in microscopy to enhance image resolution beyond the system's diffraction limits,is a well-studied technique that has gained significant traction over the last two decades.However,when translated to endoscopic systems,severe deformations of illumination patterns occur due to the large depth of field(DOF)and the 3D nature of the targets,introducing significant implementation challenges.Hence,this study explores a speckle-based system that best suits endoscopic practices to enhance image resolution by using random illumination patterns.The study presents a prototypic model of an endoscopic add-on,its design,and fabrication facilitated by using the speckle structured illumination endoscopic(SSIE)system.The imaging results of the SSIE are explained on a colon phantom model at different imaging planes with a wide field of view(FOV)and DOF.The obtained imaging metrics are elucidated and compared with state-of-the-art(SOA)high-resolution endoscopic techniques.Moreover,the potential for a clinical translation of the prototypic SSIE model is also explored in this work.The incorporation of the add-on and its subsequent results on the colon phantom model could potentially pave the way for its successful integration and use in futuristic clinical endoscopic trials.
基金supported by grants fromthe State Key Laboratory of Vaccines for Infectious Diseases,Xiang An Biomedicine Laboratory(2023XAKJ0101031)National Natural Science Foundation of China(81971665)+8 种基金Natural Science Foundation of Fujian Province(2021J011366)Medical and Health Guidance Project of Xiamen(3502Z20214ZD1016)Xiamen Health High-Level Talent Training Program,Ningxia Hui Autonomous Region Key Research and Development Program(2022BEG03127)Fundamental Research Funds for the Central Universities of China(20720210117)Fujian Province Science and Technology Plan Guiding Project(2022Y0002)National Natural Science Foundation of China(62005048)Natural Science Foundation of Fujian Province(2020J01158)Ministry of Education Industry-university Cooperative Education Project(220606053295218)XMU Undergraduate Innovation and Entrepreneurship Training Programs(2023X805,2023X808,2023Y1109).
文摘Laser speckle contrast imaging(LSCI)is a noninvasive,label-free technique that allows real-time investigation of the microcirculation situation of biological tissue.High-quality microvascular segmentation is critical for analyzing and evaluating vascular morphology and blood flow dynamics.However,achieving high-quality vessel segmentation has always been a challenge due to the cost and complexity of label data acquisition and the irregular vascular morphology.In addition,supervised learning methods heavily rely on high-quality labels for accurate segmentation results,which often necessitate extensive labeling efforts.Here,we propose a novel approach LSWDP for high-performance real-time vessel segmentation that utilizes low-quality pseudo-labels for nonmatched training without relying on a substantial number of intricate labels and image pairing.Furthermore,we demonstrate that our method is more robust and effective in mitigating performance degradation than traditional segmentation approaches on diverse style data sets,even when confronted with unfamiliar data.Importantly,the dice similarity coefficient exceeded 85%in a rat experiment.Our study has the potential to efficiently segment and evaluate blood vessels in both normal and disease situations.This would greatly benefit future research in life and medicine.
基金supported by the National Natural Science Foundation of China(Grant Nos.81930048 and 82330061)the Hong Kong Research Grant Council(Grant Nos.15217721,C7074-21GF,and 15125724)+4 种基金the Hong Kong Innovation and Technology Commission(Grant Nos.GHP/043/19SZ and GHP/044/19GD)the Guangdong Science and Technology Commission(Grant No.2019BT02X105)the Shenzhen Science and Technology Innovation Commission(Grant No.JCYJ20220818100202005)the Hong Kong Polytechnic University(Grant Nos.P0038180,P0039517,P0043485,and P0045762)the Fundamental Research Funds for the Central Universities(Grant No.QTZX25121).
文摘Retrieving high-fidelity images from optical speckles remains challenging,especially when the information in speckles is severely insufficient.To address classification through scattering media under such constraints,we propose Speckle Transformer,a vision-transformer-based model that directly classifies objects using raw speckle patterns without intermediate image retrieval.By leveraging inherent features within speckles to extract discriminative features,our approach achieves nearly 90%accuracy for classifying speckles encoded with different images,outperforming traditional retrieval-classification pipelines by up to five times,even with extreme information sparsity(i.e.,1/1024 speckle regions of interest).In addition,we quantify speckle information capacity via information entropy analysis,demonstrating that classification accuracy correlates strongly with the information entropy of speckle autocorrelation.We not only overcome limitations of conventional methods but also establish a paradigm for real-time classification in scattering environments with constrained data.
基金This research is supported by the National Natural Science Foundation of China(51975116)Natural Science Foundation of Shanghai(21ZR1402900)the Fundamental Research Funds for the Central Universities and Graduate Student Innovation Fund of Donghua University(CUSF-DH-D-2021057).
文摘This paper discusses and studies the composition and characteristics of biospeckle on the surface of bone tissues.We used a laser speckle device to capture biospeckle patterns from fresh pig bone tissue.Traditional speckle activity metrics were used to measure the speckle activity of ex vivo bone tissue over time.Both Gaussian and Lorentzian correlation functions were used to char-acterize the ordered and disordered motion of the bone surface,together with volume scattering,to construct the model.Using the established mathematical model of the spatio-temporal evo-lution of the biospeckle pattern,it is possible to account for the presence of volume scattering from the biospeckle of bones,quantify the ordered or disordered motions in the biological speckle activity at the current time,and assess the ability of laser speckle correlation technique to determine biological activity.
基金The project supported by National Natural Science Foundation of China
文摘When a surface is illuminated by laser,the field of diffusing reflective light can be described by Fresnel-Kirchhoff integration in the region of Fresnel.If the correlation,before and after the change of intensity field,is analysed by statistical method,three governing equations for variations of intensity field and speckle movement formulas can be obtained.In these equations,the surface motion,deformation and wavelength change are all considered to cause the speckle movement.
基金the nancial sup-port of the Project No.13.2251.21.0009 of the Ministry of Science and Higher Education of the Russian Federation.
文摘The influence of ischemia-reperfusion(I/R)action on pancreatic blood flow(PBF)and the development of acute pancreatitis(AP)in laboratory rats is evaluated in vivo by using the laser speckle contrast imaging(LSCI).Additionally,the optical properties in norm and under condition of AP in rats were assessed using a modied integrating sphere spectrometer and inverse Monte Carlo(IMC)software.The results of the experimental study of microcirculation of the pancreas in 82 rats in the ischemic model are presented.The data obtained conrm the fact that local ischemia and changes in the blood°ow velocity of the main vessels cause and provoke acute pancreatitis.
基金This work was supported by the National Key Research and Development Plan(Grant No.2020YFB1713600)Xinjiang Science and Technology Assistance Program(Grant No.2021E02060)+2 种基金the Fundamental Research Funds for the Central Universities(Grant No.FRF-TP-20-105A1 and FRF-TP-19-002A3)National Natural Science Foundation of China(Grant No.51975043)the China Postdoctoral Science Foundation(Grant No.2021M69035)。
文摘Surface roughness is commonly used to characterize material microstructure during processing,and accurate measurement of surface roughness is the premise and foundation of machining.Therefore,online non-destructive measurement of surface roughness based on the laser speckle method has become a hot issue in recent research.The improvements in surface roughness measurements based on the laser speckle method are systematically reviewed.Theory of speckle formation is introduced.The statistical properties of the speckle patterns including first-order statistical properties and second-order statistical properties are directly related to surface roughness.Surface roughness measurements based on the laser speckle method are roughly divided into the speckle contrast method,speckle correlation method,and fractal method.The three methods are described in detail,and an extensive comparison among all the methods is presented.The recent progresses and application of surface roughness measurements are reviewed.Finally,surface roughness measurements based on the laser speckle method are prospected and summarized.
基金This study is supported by the Chunhui Project(No.Z2015108)the Ministry of Education China,the Sichuan Science and Technology Program(No.2019YFG0196)+2 种基金the high-level personnel launch scientific research projects of Guizhou Institute of Technology(No.XJGC 20150105)the Science&Technology Department of Guizhou Province and Guizhou Institute of Technology Collaborative Fund LH(No.[2015]7104)the invitation for bid Project of Education Department of Guizhou Province KY(No.[2015]360).
文摘The quality of ultrasound scanning images is usually damaged by speckle noise.This paper proposes a method based on local statistics extracted from a histogram to reduce ultrasound speckle through a region growing algorithm.Unlike single statistical moment-based speckle reduction algorithms,this method adaptively smooths the speckle regions while preserving the margin and tissue structure to achieve high detectability.The criterion of a speckle region is defined by the similarity value obtained by matching the histogram of the current processing window and the reference window derived from the speckle region in advance.Then,according to the similarity value and tissue characteristics,the entire image is divided into several levels of speckle-content regions,and adaptive smoothing is performed based on these classification characteristics and the corresponding window size determined by the proposed region growing technique.Tests conducted from phantoms and in vivo images have shown very promising results after a quantitative and qualitative comparison with existing work.
基金Supported by Project of Beijing Natural Science Foundation(6113022)~~
文摘[Objective] The research aimed at investigating the application of laser speckle technology in agricultural products detection.[Method] This article described the basic principle of the laser speckle technology,provided a review of application development of the laser speckle technology in agricultural products detection,analyzed the problems in agriculture products detection using laser speckle technology and described the prospects of laser speckle technology in agricultural products detection.[Result] The laser speckle technology is a non-destructive detection technology for quality determination of agricultural products,which can be used to classify the agricultural products reasonably according to the quality of agricultural products.[Conclusion] The article provided reference and consult for laser speckle detection technology research.
文摘Two speckle patterns are recorded using a video cameracorresponding to undisplaced and displaced states into the memory ofa computer. After one pattern is added to another, the displacementof the measured points can be calculated by using the Fouriertransform. The expression of displacement field is deduced fornon-uniform displacement, and as an example, a rotatanle disc istested for illustration. The re- sults prove that the present methodis promising.
基金supported by the SEOUL R&BD NT070079,Korea,the ITRC(Information Technology Research Center)support program supervised by the ⅡTA(Institute for Information Technology Advancement)
文摘One of the advantages of laser speckle is detecting microvascular through image processing. This paper proposes a new image processing method for laser speckle, adaptive window method that adaptively processes laser speckle images in the space. Disadvantage of conventional fixed window method is that it uses the same window size regardless of target areas. Inherently laser speckle contains undesired noise. Thus a large window is helpful for removing the noise, but it results in low resolution of image. Otherwise a small window may detect micro vascular but it has limits in noise removal. To overcome this trade-off, the concept of adaptive window method is newly introduced to conventional laser speckle image analysis. In addition, the modified adaptive window method applied to other selection images. We have compared conventional Laser Speckle Contrast Analysis （LASCA） and its variants with the proposed method in terms of image quality and processing complexity, Moreover compared the result of the accompamed changing sdection images have also been compared.
文摘Speckles in images formed by a laser beam are interference noise arising due to coherent nature of laser radiation. As the number of projection systems using laser light sources increases, new methods and devices appear for reducing the contrast of speckle-noise and thereby suppressing it. Taking into account the long-standing nature of the problem and the continuing relevance of its solution, this review discusses modern practical methods and devices—despecklers, used to reduce the speckle contrast and to achieve high quality of projected images. The review discusses the nature of the speckles appearance, considers their statistical properties, and describes the measurement of the speckle contrast. The requirements for despecklers are considered, the most important of which are speckle suppression efficiency, simplicity of design and compactness, low power consumption and low optical loss. The characteristics of different types of despecklers, including diffusers, devices based on electroactive polymers, optical waveguides, colloidal solutions and liquid crystals, as well as orthogonal phase matrices and diffraction gratings proposed as despeckers, are examined in detail. It is shown that despecklers with decorrelation of the phase front based on the mirror deformation and optical fiber have less light losses. Electro-optical-liquid crystal despecklers do not have mechanically deformable or moving elements that reduce the reliability and durability of operation, and are more compact and simple in design. A comparative table of characteristics of the most effective despecklers in which the speckle contrast is reduced to ten percent or less, with an indication of their advantages and disadvantages, is given.
