Abstract An acousto-optic modulator (AOM) was used in combination with two-beam multipoint laser Doppler velocimetry (MLDV) to achieve advanced blood flow observation for simultaneous determination of the magnitude and direction of the blood flow velocity. To measure the shear stress around the blood vessel wall, especially in regions near obstructions, the shear rate (velocity gradient) in a pulsatile blood flow was measured using the AOM in combination with two-beam MLDV (AOM-MLDV). In addition, the blood viscosity was measured using a rotating viscometer for the estimation of shear stress. Based on the measurement results, the shear stress could be estimated as the product of the viscosity and the shear rate, which was identified determined from the velocity distribution. The blood flow velocity was found to increase in the region around the obstruction in the flow channel. Complex flows formed as a result of the obstruction, and the shear stress was observed to reach a peak value around the obstruction based on the AOM-MLDV results. This paper presents a novel blood flow detection system that provides real-time state determination capabilities using acousto-optic modulation and LDV.

中文翻译：

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使用激光多普勒测速仪结合声光模块对血液剪切应力进行光学可视化

摘要 声光调制器（AOM）与两光束多点激光多普勒测速仪（MLDV）相结合，实现先进的血流观测，同时确定血流速度的大小和方向。为了测量血管壁周围的剪切应力，尤其是在靠近障碍物的区域，使用 AOM 结合两束 MLDV (AOM-MLDV) 测量脉动血流中的剪切率（速度梯度）。此外，使用旋转粘度计测量血液粘度以估计剪切应力。根据测量结果，剪切应力可以估计为粘度和剪切速率的乘积，剪切速率由速度分布确定。发现血流速度在流动通道中障碍物周围的区域中增加。由于障碍物形成了复杂的流动，根据 AOM-MLDV 结果，观察到剪切应力在障碍物周围达到峰值。本文提出了一种新型血流检测系统，该系统使用声光调制和 LDV 提供实时状态确定功能。