Automatic Detecting System For Surface Defection Of PCB

PCB(printed Circuit Board)plays an important role in electronic equipment and develops towards high complexity and high precision.The traditional PCB detection method can not meet the production needs of enterprises and the price of related products abroad is high.It is very important to study a low cost PCB surface defect detection system.Based on machine vision technology and image processing method,a PCB surface defect detection system is constructed in this paper.The system is divided into two parts:hardware system and software system.The hardware system includes three parts:optical lighting system,image acquisition system and auxiliary hardware system.The optical lighting system and the auxiliary adjustment system provide external conditions for image acquisition.The image acquisition system is responsible for the acquisition of PCB images.The software system uses VC 6.0 as the basis to write the interface,using image preprocessing,image registration,threshold segmentation,image recognition and other methods to analyze and process the captured image,to identify whether the image is defective or not.The main contents of this paper are as follows:1.In this paper,the current situation and traditional detection methods of PCB surface defects at home and abroad are studied,and the common defects of PCB bare plate are analyzed and classified.2.The surface defect classification of PCB bare plate and the working principle and overall structure of the detection system are analyzed.3.According to the working principle of PCB surface defect automatic detection system,the hardware part of the system is designed,and the physical model is produced.4.According to the working principle of the PCB surface defect automatic detection system,the software part of the system is designed,and the software is programmed with VC 6.0 to analyze and process the collected images and identify the defects.5.According to the characteristics of various defects in PCB bare board,different defect recognition methods are used.The experimental results show that the automatic PCB surface defect detection system based on machine vision can quickly and accurately detect whether the PCB is up to standard and the cost is low to meet the needs of small and medium-sized enterprises.