Thomas,
We evaluated several AOI machines and narrowed the field to two, YESTech and MIRTEC. We had an opportunity to work with both of these machines on our production floor. In our experience, the MIRTEC machine simply outperformed the competitive system, especially with regard to solder joint inspection. We also performed a simple Gage R&R test on the two machines in which we ran our test boards multiple times on each machine and recorded the defects after each pass. Again, MIRTEC gave us the most consistent and repeatable results.
On a side note, the MIRTEC machine was about 2.5 times faster with 20% less false calls. Although this helped with my ROI, performance was the main concern. We cannot afford escapes... PERIOD! If you are looking for a solid AOI machine that is simple to program and extremely accurate my recommendation is MIRTEC. We have five machines including an MV-7xi configured with five, 5meg cameras, and a 3D laser system. Company support has been great.
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