AiVibeQuality, Reliability & Maintenance
Automated Optical Inspection (AOI)
Automated optical inspection uses cameras, lighting and image processing to inspect products automatically for visible defects, most commonly printed circuit board assemblies checked for missing, misplaced or defective components and solder joints.
An AOI system captures images of the product under controlled lighting, often from several angles and with different colours, and compares them with reference images, design data or rules describing acceptable features. In electronics assembly, two-dimensional systems inspect component presence, polarity, position and markings, while three-dimensional systems measure height using techniques such as structured light projection, improving detection of lifted leads, coplanarity problems and solder volume defects. Solder paste inspection, a related process, measures printed paste deposits before components are placed.
In surface-mount lines, AOI is commonly placed after solder paste printing, after component placement and after reflow soldering, giving fast feedback to the process. The same principles are used beyond electronics, for example to inspect labels, packaging, castings, machined parts, fabrics and painted surfaces, often with deep learning models for defects that are hard to describe with rules. Automated inspection gives consistent, documented results at line speed, whereas manual visual inspection suffers from fatigue.
AOI detects only what cameras can see, so hidden joints such as those under ball grid array packages need X-ray inspection. Systems must be tuned to balance missed defects against false calls, which waste operator time and erode trust. Inspection programs need maintenance when products or suppliers change, and inspection data are most valuable when fed back to process control. IPC-A-610 is widely used as the acceptability standard for electronic assemblies.
Key points
- Automatically inspects products with cameras, lighting and image processing.
- Widely used after paste printing, placement and reflow in SMT lines.
- 3D AOI measures height to detect lifted leads and solder volume defects.
- Cannot see hidden joints, which need X-ray inspection.
Where AiVibe comes in
AiAmbA AI Factory use cases include visual inspection on textile, automotive and electronics lines, with existing lines retrofitted with edge devices.
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