针对接触式芯厚测量设备不能测量直径小于 0． 30 mm 的微钻的问题，提出了基于图像处理的微钻芯厚测量方法． 为了提高设备的检测精度，对 3 种亚像素边缘检测算法进行了对比，综合各算法的误差和耗时，选取灰度矩法为亚像素边缘检测算法;并通过对直径 0． 40mm、0． 25mm 的钻头的芯厚测量来验证文中提出的测量方法的精确性． 结果表明:对直径 0． 40mm 的钻头，基于图像处理的芯厚测量方法的重复精度可达 1μm，重复精度优于接触式芯厚测量方法;对于直径 0． 25mm 的钻头，基于图像处理的芯厚测量方法的重复精度仍可达到 1μm，说明该方法能够有效测量直径小于 0． 30mm 的微钻的芯厚．

As the traditional instruments for web thickness measurement is inefficient for the micro drills with an outer diameter of less than 0.30mm,a novel method on the basis of image processing is proposed.In order to im- prove the instrument accuracy,a comparison is made among three subpixel edge detection algorithms,and the gray moment algorithm is selected as the subpixel edge detection algorithm by comprehensively considering the error and time consumption.Then,two micro drills respectively with the diameters of 0.40mm and 0.25mm are used to veri- fy the proposed method.The results show that，for the micro drill with a diameter of 0.40mm,the proposed method on the basis of image processing presents a repeatability of 1μm,which is higher than that of the traditional contact measuring method; and that the repeatability keeps 1μm even for the micro drill with a diameter of 0.25mm,which means that the proposed method is effective in measuring the web thickness of micro drill with a diameter being less than 0.30mm.