What are the differences between AOI automatic optical inspection equipment and X-RAY inspection equipment in SMT assemb

AOI is the abbreviation of Automatic Optical Inspection in English. Its basic principle is to check whether the SMT surface mount and DIP through-hole component mounting and soldering are correct, whether the position is good, and whether there are defects such as missed mounting and reverse alignment through the reflection of red, green and blue light. It is an automated inspection device.

AOI (Automated Optical Inspection) is an automatic optical inspection instrument and equipment applied on the Surface mount Technology (SMT) production line. It can effectively detect the printing quality, mounting quality and solder joint quality.

By using AOI automatic optical inspection instruments as tools to reduce defects, errors can be identified and eliminated in the early stage of the assembly process to achieve good process control. Early detection of defects will prevent defective products from being sent to the assembly stage of subsequent processes. AOI automatic optical inspection instruments will reduce repair costs and avoid scrapping non-repairable circuit boards.

• Final quality: Usually placed at the very end of the SMT production line, it is used to check for product defects in SMT.
• Process control: Placed respectively after the printing machine and the surface mount technology (SMT) placement machine, it is used to inspect defects in the SMT process and provide feedback data.

• Solder paste defects: including presence or absence, deviation, insufficient solder, excessive solder, open circuit, short circuit, contamination, etc.
• Part defects: including missing parts, offset, skew, standing upright, standing sideways, overturned parts, reversed polarity, wrong parts, damage, etc.
• Solder joint defects: including insufficient solder, excessive solder, and continuous solder, etc.

X-RAY non-destructive ray inspection equipment is an X-ray fluoroscopy machine. Its principle is to utilize the characteristic that X-rays can penetrate non-metallic substances. It adopts a structure combining a high-resolution enhanced screen and a sealed micro-focus X-ray tube. Through non-destructive X-ray fluoroscopy inspection, clear internal images of the product can be observed in real time. Check whether the lower parts of components such as BGA are soldered well and whether there are any short circuits, etc.

The rapid development of high-density packaging technology has also posed new challenges to testing technology. To meet the challenges, new testing technologies are constantly emerging, and X-ray inspection technology is one of them. It can effectively control the welding and assembly quality of BGA. Nowadays, X-ray inspection systems are not only used in laboratory failure analysis, but have also been specially designed for PCB assembly in production environments and the semiconductor industry, providing high-resolution X-ray systems.

X-RAY non-destructive testing machines and X-Ray inspection machines provide non-destructive testing solutions for industries such as PCBA, SMT assembly, semiconductor devices, batteries, automotive electronics, solar energy, LED packaging, hardware parts, and wheels.

• It is suitable for inspecting various types of SMT chips, electronic wafers, semiconductor chips,BGA, CSP, SMT, THT, Flip Chip and other components, etc.
• Welding/packaging inspection X_RAY(whether the structure, solder joints, and solder lines are de-soldered, poorly soldered, missed soldered, wrongly soldered, etc.).

• BGA soldering inspection (bridging, open circuit, cold soldering voids, etc.
• The connection conditions of ultra-fine parts such as system LSI (broken wires, solder joints)
• Semiconductor inspection of IC packaging, rectifier Bridges, resistors, capacitors, connectors, etc
• Inspection of PCBA soldering conditions
• Internal structure inspection of hardware components, electric heating tubes, pearls, heat sinks and lithium batteries, etc

The current application and the transformation process of effective quality control methods in the SMT patch processing industry. The traditional quality control methods for SMT patch soldering production and processing all relied on manual visual inspection (referred to as visual inspection). Next, microscopic optical technology is introduced, and optical magnification technology is used for the quality inspection of industrial circuit boards. Later, it was found that the application of this technology was increasingly unable to keep up with the needs of industrial development. During this period, the AOI optical inspection instrument emerged. In China, after more than ten years of development in optical inspection technology, AOI has become an indispensable quality inspection device for PCBA surface mount technology production and processing.

The AOI automatic optical inspection instrument has effectively solved the thorny problem of manual appearance inspection of flexible circuit boards, significantly reducing the labor cost for inspection and lowering costs.

With the increasingly fierce market competition, terminal electronic product manufacturers are putting forward more and more strict requirements for the quality assurance of PCBA, among which the quality of the pads used for soldering chips is particularly strict. At present, for the appearance inspection of the gold surface of PCBA pads, many domestic enterprises still adopt the method of manual visual inspection, which has disadvantages such as low efficiency, poor reliability and low inspection quality. Due to the continuous rise in labor costs, the density of circuit integration will become increasingly higher, and manual visual inspection will inevitably be gradually phased out by machine vision inspection.

The detection technology of AOI automatic optical inspection instruments is becoming increasingly intelligent, gradually growing and extending in the form of quality robots. Under the premise that the performance of AOI automatic optical inspection instruments is constantly improving and their integration capabilities are getting stronger and stronger, AOI automatic optical inspection instruments bring customers not only inspection but also a powerful tool for quality traceability and quality assurance. While we are constantly developing new products to enhance performance, we are also conducting research on AOI applications. We not only aim to teach our customers how to use AOI but also encourage them to make good use of it. We firmly believe that as long as it is flexibly applied, the prospects of visual AOI are immeasurable and the value it brings to customers is also tremendous.