5、 Function selection
The functions of Yier AOI equipment are generally complete, and there is no big difference between them. The following is a brief description of some common work.
1. The resolution of AOI should be judged by the size of the pixel, that is, the spatial resolution. The size of pixel is not the standard to judge the detection ability of AOI. To be exact, the size of pixel is the factor that determines the size of pixel per unit area. If the unit area is different, no matter how high the pixel is, there is no comparability. For example, the FOV of an AOI is 1216 mm. If this AOI uses a 300 megapixel camera, then the resolution of this AOI is only 25 microns. It can only detect components with package size of 0402 or more. But if the AOI uses a 2 megapixel camera, the resolution of this AOI will be 10 microns, and it can detect components with package size of 01005 or above. On the other hand, if the AOI uses a 2 megapixel camera, if its FOV is 2432 μ m, then its resolution is only 20 μ m, so it can only detect components with package size above 0402 even though it has high pixels. Generally speaking, the AOI resolution of PCBA board with component size above 0402 should be at least 20 μ M. The resolution of AOI for PCBA board with package size above 0201 should be at least 15 μ m, and that for PCBA with package size above 01005 should be at least 10 μ M.
2. Selection of special functions. If you want to test PCBA of multi board, you must
Select AOI with springboard function, that is, AOI with region selection function. If you use AOI as the process control of quality, you must select AOI with RPC function when selecting AOI, that is, AOI with real-time process control.
3. The selection of CAD. At present, all AOI devices have the function of importing CAD data, but the use of this function is not very efficient for PCBA boards with fewer devices, but it can achieve twice the result with half the effort for PCBA boards with more components.
4. Selection of SPC SPC is process statistical control. Statistical control has no real-time process control RPC important RPC can not only carry out real-time statistical analysis, but also carry out early warning, which can keep the production line in normal operation for a long time.
5. The choice of repeatability, false positive rate and false negative rate. The higher the repeatability, the more stable the performance of AOI, the lower the false positive rate and the lower the missed judgment rate.
(Editor in charge：admin)
