光全反射法是测量真实接触面积的常用手段,然而用其测得的接触图像小,接触斑点的边界模糊。作者应用波动光学的有关理论对光全反射法的基本原理进行了深入的研究,进而提出用图像处理技术识别接触区域的边界。通过钢球与平面接触的试验研究,验证了这种测量方法的准确性和可靠性,并且根据试验结果分析了赫兹接触理论的局限性。文章最后还阐述了对典型工程表面接触面积的测量与结果。 Light total reflection method is a common measure of the true contact area, however, the contact image measured with it is small and the boundaries of the contact spots are blurred. The author applied the theory of wave optics to thoroughly study the basic principle of total reflection of light, and then proposed using image processing technology to identify the boundary of the contact area. The experimental study of the contact between the steel ball and the plane verifies the accuracy and reliability of this measurement method and analyzes the limitations of the Hertzian contact theory based on the experimental results. Finally, the article also elaborates the measurement and result of the contact area of ​​the typical engineering surface.