Abstract:In order to improve the automation degree of non-contact tonometer and speed up the efficiency of human eye pupil location, a multi template matching algorithm based on XLD contour is proposed, which can realize the rapid and accurate location of human eye pupil, increase the detection range of non-contact tonometer pupil location and improve the automation level. At the same time, for the false detection image, bilateral filtering, threshold segmentation and corrosion expansion processing are adopted, and then the pupil region is obtained by setting parameters. Finally, Hough transform is used to reposition the false detection image. The experimental results show that the positioning success rate of the proposed method is more than 99%, the error is within 5 pixels, and the average positioning is 0.121s. It can accurately and quickly obtain the central coordinates of the human eye pupil, and can meet the requirements of the non-contact tonometer for accurate and rapid pupil positioning. At the same time, it has strong robustness and generalization to interference factors such as individual pupil difference, posture difference, partial occlusion of pupil, influence of edge spot and so on.