目的 准确检测出药瓶印刷字的缺陷。方法 采用目前流行的SIFT特征点提取算子，选用欧氏距离进行初匹配，RANSAC进行精确匹配。结果 药瓶在传送过程中不管发生怎样变化，都能被检测出其印刷字的缺陷，成功剔除不合格药瓶。结论 实验结果表明该方法能够精确地提取图像特征点，准确地匹配图像特征点对。

The work aims to accurately detect the defects of printed words on the medicinal glass bottles. The currently popular SIFT feature point extraction operator was adopted. Then, the Euclidean distance was used for the initial matching, and the RANSAC was used for the exact matching. In the transmission process, no matter how the medicinal bottle changed, the defects of the printed words could be detected. Thus, the unqualified medicinal bottles could be successfully removed. The experiment results show that this method can accurately extract the image feature points and match the image feature point pairs.