Laser Speckle Modeling and Simulation for Biophysical Dynamics: Influence of Sample Statistics

Abstract

Laser speckle is a statistical phenomenon and should be treated as such when establishing experimental parameters for using laser speckle techniques to infer information about the dynamics of a coherently illuminated medium, such as biological tissue. Herein, we demonstrate that when sampling (imaging) speckle patterns, it is critical that the sampled speckle patterns are unbiased estimators of the underlying random speckle field. If this condition is not met, the quality of the results will be compromised. Specifically, this study examines the effects of first and second order spatial statistics of speckle intensity images on laser speckle contrast imaging results. Finally, it is recommended that when using speckle techniques such as laser speckle contrast imaging, investigators should examine the first and second order spatial statistics of a speckle image prior to collecting actual data. If this examination reveals that the imaged speckle intensity image is not an unbiased estimator of the underlying random speckle field, then adjustments should be made to ensure that the images taken are unbiased estimators of the true speckle field.

A Portable Compact System for Laser Speckle Correlation Imaging of Artworks Using Projected Speckle Pattern

“…In Figure 4 , we show the appearance of the projected and secondary patterns and their superposition resulting at the camera observation plane. The simulations of the objective diffuser pattern and the subjective surface pattern were performed following the authors of [ 35 , 36 ].…”

Diffuse Speckle Contrast Analysis (DSCA) for Deep Tissue Blood Flow Monitoring

“…Ever since the clever idea of turning a blurry speckle image into a sharp ow image by a very simple image processing algorithm was presented [61], laser speckle owmetry has enjoyed a vast amount of attention in biomedical optics [28,29]. Although it was hard to obtain quantitative blood ow measurement from the resulting image of speckle contrast, it has found plenty of application in super cial blood vessel imaging, and there has been a lot of studies aiming to make LSCI a quantitative tools as well [13][14][15]27,30,34]. Especially, combining LSCI with sidestream dark eld (SDF) microscopy has been very successful recently [35,36].…”

Pengaruh Variasi Sudut Datang Dan Sudut Tangkap Cahaya Pada Nilai Kontras Citra Spekel Beras Berbasis Gui Matlab

“…Sehingga akan memberikan informasi mengenai pengaruh variabel yang diteliti melalui persebaran intensitas cahaya yang terbentuk pada citra [4]. Teknik LSI memiliki prinsip kerja yang mudah untuk dipahami, selain itu metode ini juga memiliki jangkauan penerapan yang luas dan tingkat ketelitian yang cukup tinggi.. Hal ini yang mendorong pemanfaatan metode LSI sebagai alat yang kuat untuk pengujian maupun pemantauan sampel secara optis [5].…”