Research On Key Technologies Of Automatic Optical Inspection Of ACF Particles In Touch Screen

Magnetic material is a new type of magnetic material composed mainly of NdFeB.Because of its good magnetic properties,it is widely used in the fields of electronic industry,space industry,machinery industry and other fields.Magnetic materials will cause defects on the surface due to various reasons in the process of production and processing,and seriously affect their use functions.First,the appearance defects will make the magnetic distribution of magnetic materials uneven;secondly,the magnetic material is easily corroded during the use process.The appearance defect causes the protection layer to be destroyed more easily,which seriously affects the service life of the magnetic material products.At present,there is not a complete set of magnetic material testing system at home and abroad.In this paper,based on the actual requirement of magnetic material detection,a Automatic Optical Inspection(AOI)system based on machine vision is designed.The main research results and related contents of this paper are as follows:(1)because the industrial production line is in high speed motion state and the edge of the magnetic material has a more obvious arc chamfering,the image contour collected by the ordinary image acquisition system in the high-speed state will have obvious dragging,and the edge corner of the image is easy to appear the shadow and cover the real information of the defect,so the magnetic material is based on the magnetic material.In this paper,a set of machine vision detection system is designed scientifically,and the image acquisition system of high precision and adaptable optical detection system is made up of the array camera,the telecentric lens,the fixed focus lens and the different light sources.The experiment shows that the optical acquisition system designed in this paper can collect clear images of the non shadowless outline of the magnetic material and the edge chamfering in the case of up to 450 /min,which can meet the demand of industrial production.(2)according to the characteristics of magnetic material surface defects,an algorithm for magnetic material surface is designed to deal with the collected images.For the first time,the algorithms of template matching and operation calculation are applied to the detection of the surface defects of magnetic materials.By adjusting the template generation angle,the matching similarity coefficient and the open operationkernel size,the high speed and accurate algorithm effect is achieved.The experimental results show that the algorithm can detect the defects with the minimum area of 0.01 square millimeters.Moreover,the detection time is less than 133 ms,which meets the demand of industrial online production.