The Contour Extraction System Of Glass Lens Based On Machine Vision

Vision is the most important human sense,and it is the main way for human beings to understand the outside world.Machine vision is to make the machine have the same function as the human eye,and can be used in the fields of detection,identification,measurement,etc.Machine vision systems have high-efficiency and high-automation features compared to manual inspection.With the continuous development of machine vision technology and the increasing demand for human life and production,machine vision systems are now widely used in aviation,electronics,medicine,automotive,printing and packaging.The main research contents of this article include:In this paper,the key technologies such as camera calibration,image detection and contour tracking in the spectacle lens contour extraction system are deeply studied.Using an embedded system,an eyeglass lens extraction system based on machine vision was developed.The monocular vision system was used to obtain the image of the spectacle lens.Then the image was preprocessed and the outline of the lens was extracted by the eight-neighborhood contour tracking method.Finally,the camera is calibrated and the resulting distortion factor corrects the contour of the lens.This system does not have the limitations of the PC platform and can be applied to daily production of ophthalmic lenses,shortening the production cycle of ophthalmic lenses.In the process of studying camera calibration,the existing calibration methods are studied,and two calibration methods are improved.The first method is an improved camera calibration method based on the traditional two step method.This method can be calibrated by shooting a single plate image.The calibra tion process is more concise than the traditional two step method and has high precision.It is completely suitable for the lens contour extraction system in this paper.The calibration board used in this method is very complicated.Based on this,second methods of using simple calibration board are obtained.The second method is a simple and suitable camera calibration method for contour detection.The method uses square calibration plates.Process the picture at the pixel level.Only one square calibratio n board can complete the calibration and simplify the steps of camera calibration.At the same time,a new method is used to find the distortion center.The accuracy of this method is slightly worse than that of the first method,but it still meets the req uirements of this system,and the calibration board is simple and easy to obtain.