The Technology Of The Detection For Defects InBGA Package Based On X-Ray System

Aimed at the special requirements of the BGA solder joint defect detection in X-ray printed circuit board, this paper studies the defect detection and recognition technology based on X-ray real time imaging.In the field of printed circuit board detecting, the performance and assembly of BGA package is better than conventional components, but, because of the defects, such as blowholes, solder bridge and poor soldering, appear as the solder joints under the BGA package devices are not visible, which can affect the quality and security of PCB products . It is difficult to test the BGA package solder joints. So BGA solder joint image defect detection is very important.Because of this, this paper discuss The Technology of the Detection for Defects inBGA Package Based On X-Ray System,The main contents include:In the BGA-ray image preprocessing section, because of the BGA-ray image itself has a low edge blur and contrast ,we discussed based on fuzzy mathematics method of anisotropic diffusion for image denoising and image intensity transformation. Fuzzy anisotropic diffusion based image denoising algorithm can effectively filter out the noise BGA-ray images, and can better maintain the image detail information.In the BGA-ray image segmentation section, we discusses several classical image segmentation algorithm, and using the maximum projection principle to the Gaussian function set as the base function set, the orthogonal projection decomposition method to reconstruct the image histogram, the reconstructed Re-use of the minimum error method of image segmentation. Experiments show that this method is effective.In the BGA solder joint defect detection and automatic identification section, we discuss through the solder joint location, contour extraction and tracking algorithm are the coordinates of solder joints, solder area, with void of solder joint defect rate parameters, analysis the defect feature, automatic identification to determine BGA solder joint defects.