Open AccessCorrecting speckle contrast at small speckle size to enhance signal to noise ratio for laser speckle contrast imaging
Author(s) -
Jianjun Qiu,
Yangyang Li,
Qin Huang,
Yang Wang,
Pengcheng Li
Publication year - 2013
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.21.028902
Subject(s) - speckle pattern , speckle noise , optics , contrast (vision) , pixel , speckle imaging , contrast to noise ratio , signal to noise ratio (imaging) , signal (programming language) , noise (video) , physics , image quality , materials science , computer science , computer vision , image (mathematics) , programming language
In laser speckle contrast imaging, it was usually suggested that speckle size should exceed two camera pixels to eliminate the spatial averaging effect. In this work, we show the benefit of enhancing signal to noise ratio by correcting the speckle contrast at small speckle size. Through simulations and experiments, we demonstrated that local speckle contrast, even at speckle size much smaller than one pixel size, can be corrected through dividing the original speckle contrast by the static speckle contrast. Moreover, we show a 50% higher signal to noise ratio of the speckle contrast image at speckle size below 0.5 pixel size than that at speckle size of two pixels. These results indicate the possibility of selecting a relatively large aperture to simultaneously ensure sufficient light intensity and high accuracy and signal to noise ratio, making the laser speckle contrast imaging more flexible.