Effective analysis of optical inspection machines (IMPACT 2011)

Application AOI, automated optical inspection is an automated vision inspection of PCB during the manufacturing process. It is used to scan the inner layers and outer layers of PCB after the processes of etching and stripping. After the circuit patterns on inner layers and outer layers are formed, there may be defects on them such as open circuit, short circuit, missing copper, excess copper, etc. After scanning by AOI machine, the defects which do not meet the manufacturer´s requirement will be identified by the machine. These defects may be repaired by workers before next production process. If the defects cannot be repaired or there are too many defects, then the boards may be counted as failure and will not be passed to next production process. In this way, AOI can detect problems early in the production process, so faults would not be passed to next production process and production cost could be saved. Therefore AOI can increase the quality of PCBs and reduce the production cost.