研究了利用激光散斑的动态特性对涂料的干燥过程进行监测的基本原理和激光散斑动态特性的实时描述算法，提出了差分平均值算法.通过求取一定间隔两帧散斑图的差分图，利用差分图的灰度分布直方图来定性地描述激光散斑动态特性的强弱，用差分图的灰度平均值定量地描述激光散斑的动态特性的变化.实验结果表明，利用激光散斑的动态特性可以实现对涂料干燥过程的无损、在线监测，该算法可以在监测过程中实时给出结果，具有运算时间短、对硬件要求低的特点.

The basic principles based on dynamic characteristics of laser speckle for monitoring of the paint drying process was studied. The processing algorithms of realtime detection were analyzed.A differenceaverage algorithm of dynamic speckle was proposed. In this algorithm, gray distribution histogram of the difference image was used to qualitatively describe the strength of the dynamic characteristics of the laser speckle, and the average gray level of the difference image was used to quantitative describes the changes of speckle. Experimental results show that dynamic characteristics of speckle can be used to nondestructive and online monitor the paint drying process, and the differenceaverage algorithm can be given realtime results in the monitoring process with shorter computation time and lower hardware requirements.