Application Conditions of Laser Speckle Contrast Imaging Analyzer Based on Dynamic Scattering Material

Objective: To find out the factors that affect the measurement results of laser speckle contrast imaging (LSCI) by simulating using conditions. Methods: Using fresh animal blood as dynamic scattering material, the practical conditions and parameters were simulated to explore the application conditions of laser speckle imaging analyzer. The LSCI device we used was a commercial product (Laser Speckle Blood Flow Imager Ⅱ, SIM BFI WF, SIMOpto-Technology Co., Ltd, Wuhan, China.). First, in a certain range of blood flow velocity experiments, we aimed to get the corresponding blood flow velocity detection range of the laser speckle contrast imaging analyzer. Then, we explored the changes of laser speckle contrast imaging analyzer results under five conditions : different surface colors ; different exposure times (1-15ms), different light conditions (shading, lamplight and no light), differentdistances between the probe and the object (15, 20, 25, 35, 35, 40, 45, 50cm), and different angles between the probe laser beam and the object (90°, 85°, 80°, 75°, 70°, 65°). Results: 1. Within a certain range of blood flow velocity, the laser speckle contrast imaging analyzer could relatively and accurately reflect the changes in blood flow velocity. 2. The surface color of the object, exposure time, the distance between the probe and the object, and the angle between the probe laser beam and the object all had an influence on the results. Conclusion: The color of the object, the set of exposure time, the light condition, the probe distance and the angle between probe laser beam and object are all LSCI influence factors.