针对传统的扩散系数测量方法存在测量精度不高、不能实现非接触或可视化测量、对环境要求严苛等缺陷，本文提出了一套基于中空直角三角水槽实现液体扩散系数可视化测量的方法. 该方案将线激光入射至注有两种液体的直角三角水槽，通过激光穿过水槽后的折射光斑，可视化反映液体扩散产生的折射率渐变. 先利用图像处理技术测量线激光折射后的偏移量，再结合折射率与浓度的线性关系和Fick定律导出的理论公式，计算出两种液体的等效互扩散系数. 通过实验测定，浓度为5.5 mol/L的甘油溶液的扩散系数为7.47×10-10 m2/s，125组数据标准差为7.12×10-12 m2/s，变异系数小于1%. 测量数据反映实验结果具有较强的一致性，可信度高.

Traditional measurement methods of diffusion coefficient have some defects, such as low accuracy, non-visual measurement, and critical environmental requirements. Therefore, a visualized measurement method of liquid diffusion coefficient based on a hollow right-angle triangle cell (RATC) has been provided. For this method, a linear laser is injected into the RATC filled by two kinds of liquid with different refractive indexes. The refractive index gradient generated by the liquid diffusion region can be visually reflected by the refractive spot after the laser passes through the RATC. For the refractive spot indicates the diffusion affecting on the refractive index, the equivalent interdiffusion coefficient of the two liquids is able to be calculated by combining the linear relationship between refractive index and concentration and the theoretical formula derived from Fick′s law. The experimental results show that the diffusion coefficient of 5.5mol/L glycerin solution is 7.47×10-10 m2/s, and the standard deviation of 125 groups of data is 7.12×10-12 m2/s. Meanwhile, the coefficient of variation is less than 1%, which shows that this method has strong consistency and high reliability.