Image Acquisition And Processing In Machine Vision Inspection For SMT Assembly Products

As the installation of the components on the printed circuit board has generally adopt the surface mounted technology, the integrated level and the density of the products are further improved, and the volume of the components becomes smaller, which make the installation and produce realized automation in the electronic manufacturing industry. The traditional examination methods can not satisfy the new surface mounted technology both in measuring ability and speed, and the quick, reliable and automatic examination for the quality of installation has become an important technology, which can improve the automatic level and the product quality. The automatic examination based on machine vision is the most advanced, fast, reliable and automatic method at present.This paper has studied the image collection and image process during the automatic examination for the surface mounted components, and the hardware structure of the machine vision platform is discussed. The paper firstly made the review and analysis to the surface mounted technology, Introduced the domestic and foreign situations of the trade, and explainedthe positive meaning of the study. The paper secondly studied the hardware design of the examination system which based on the machine vision, and proposed four guidelines that light source need to be satisfied, in addition, two light sources have been chosen using in different objects. Thirdly, high precision X-Y platform has been used in examination system for the innovative camera calibration. The paper fourthly studied the similarities and differences between the travelling salesman problem and the path planning of image collection when the surface mounted products are examined. After the contrast, the ant colony algorithm is applied in the path planning of image collection and proposed an improved method, which can inhibit the shortcoming of the basic ant colony algorithm. In the part of the image process, the author summarized certain project traits in image mosaic of the surface mounted products, and designed the quick image mosaic method in a situation that the illumination is not even. At last, the author proposed an wavelet transform and open algorithm to overcome the limitation, which will come into being when the image content is not considered by the traditional image enhancement algorithms.