Speaking of AOI detection, it is generally divided into online AOI detection and offline AOI detection. The former mainly checks the components for missed inspection, wrong parts and placement quality after placement, while the latter mainly records test data and conducts statistical analysis. However, in the actual production of the current SMT patch processing plant, although AOI is more efficient than manual visual inspection, after all, the results are obtained through image acquisition and analysis and processing, and the current image analysis and processing related software technology has not reached the human brain level. . Therefore, it is inevitable that there are some special situations in SMT patch processing, such as misjudgment and missed judgment of AOI. The following Sanjing summarized the main problems in the inspection of AOI after the completion of the SMT patch:

1. The process requirements and standard definitions of more tin, less tin, offset, and skew are different, which may easily lead to misjudgment.

2. The capacitance value is different but the specification size and color are the same, which is easy to cause missed judgment.

3. It is not possible to detect invisible solder joints such as BGA and FC flip-chip components.

4. Different character processing methods cause greater differences in the accuracy of polarity judgments.

5. There are problems with the detection of screens, shields, and shadow points.

6. Some AOIs with lower scores cannot do OCR character recognition testing.

7. Most AOIs have ambiguities in their understanding of virtual welding, causing evasiveness.

8. The detection speed of most AOI products is slow, and a few AOIs using scanning methods are faster, but the rate of misjudgment is higher.

9. Most AOI programming is complex, cumbersome and long adjustment time, so it is not suitable for scientific research units, small OEM factories, production units of multi-specification and small-batch products.

In view of the above problems, we suggest that SMT processing plants need to add some auxiliary equipment in addition to the increase of quality control personnel in the quality control process. After all, for the production enterprise, quality is always the first, so every part of the quality control process Every step must be paid attention to.