为了解决印制电路板(PCB)缺陷检测数字化成像问题, 设计了一套高分辨力印制电路板X射线缺陷检测系统。通过分析射线源焦点尺寸对成像效果的影响, 计算出最佳几何放大倍数; 对MCP-X增强器性能进行了分析, 推导出增强器分辨力与几何放大倍数的关系, 以此计算出系统综合分辨力。根据试验可知, 系统实现了对缺陷特征值的测量, 同时对电路板BGA器件中焊点缺陷测量的最小分辨力达到0.03 mm, 完成了BGA器件不可见焊点缺陷检测要求。

In order to solve the problem of digital radiography for printed circuit board(PCB) defect inspection, an examination system was introduced for PCB defect inspection with high resolution X-ray. Through analysing the influence of the focus size of X-ray source to imaging formation, the best geometrical magnification was got. Analysing on performance of MCP-X intensifier, the relationship between the resolution of intensifier and geometrical magnification was deduced, and then we could calculate the comprehensive resolution of this system. Through the examination, it was concluded that, the system realized the measurements on defect character, the measuring accuracy to the BGA solder joint of circuit board was reached to 0.03 mm, meeting the request of inspection on invisible solder joint.