Research On Mobile Phone Lens Sorting System Based On Machine Vision

LENS is an important peripheral component of mobile phone screen, the mainfunction of which is to protect the display screen and ensure the previous to lightquality. With the development of LCD display technology and the extensiveapplication of the touch screen sensor technology, the market demand of the mobilelens is increasing by a big margin. Due to the defect of production process, there aresome defections in the lens, such as scratches on the surface and internal bubbles. So,how to sort these productions quickly and effectively becomes a big problem to lensmanufacturers. Machine vision inspection is a technology which uses machine insteadof manual testing, relying on computer science. Using machine vision to design lenssorting system, can not only reduce the artificial detection labor cost, but also cangreatly improve the detection accuracy and efficiency.Firstly, the optical and physical properties of mobile lens are analyzed.Combined with the general model of machine vision and the special requirements ofthis system, the total design framework is introduced; then, because of the opticalcharacteristics including high transparency and uniform background, a coaxiallighting system based on LED point light source is chosen and designed, combinedwith the selection principles and applicable scenes of light sources and lightingsystems; for the problems of lens having various kinds, different sizes, a motionimaging system controlled by PLC is designed, based on image segmentations; for thesize of defections being very small, combined with the principles of choosing camerasand lenses in machine vision applied in industry detection, the parameter requirementsof these are calculated and determined; some typical defects of lens are researched, animagining algorithm, the core of which is morphology processing, is putted forward,and the geometric features and classification methods of defects are also discussed.Finally, according to the independence of the partition-imaging and real-timeprocessing, a set of high concurrent PC software system is designed.Through the results of long time running test on a set of mobile cleaning andsorting system, comparing with artificial test results, we can draw a conclusion thatthe system can sort all types of mobile phone lens accurately and efficiently.