Defining Useful Pass/Fail Checks for AOI Factory Acceptance Testing
Buyers should agree on concrete pass/fail criteria before accepting an automated optical inspection machine, using known-good and known-bad boards to test detection, false calls, and cycle time.
A buyer should decide before the factory acceptance test which defects the automated optical inspection machine must catch and which false calls are tolerable, because a machine that passes every board is not useful. Ask the supplier to run a set of printed circuit boards with known defects and a set of known-good boards, then record detection results and false-call counts for each.
Use the catalog reference values as a starting point only: 3D white-light projection with 2D imaging, 10 µm XY resolution, and 0.45 s per field of view. Ask whether the acceptance boards will be inspected at those settings and how resolution and speed change when sensitivity is raised. Define pass or fail per defect type, such as missing components or poor solder joints, and state the minimum detection rate and maximum false-call rate you will accept. Include a repeatability check by running the same board twice and comparing results.
Before requesting a quote, confirm with the supplier which test boards and defect samples will be used, how results will be recorded, and whether the acceptance criteria and settings will be written into the purchase agreement.