Typically AOI systems have their optimal focus point at the surface level of the PCB assembly. Due to the focal range of the lenses used, the image is adequately sharp for a few mm’s above and below the optimal focus point. If the object is further away, the image is out of focus and inspection algorithms may have difficulty inspecting such objects reliably.
To secure optimally focused objects, the Mek GTAz head is equipped with a Motorised height adjustment system for the optical head (Z-axis adjustment). This system can move the complete inspection head, including the lighting system, to bring objects optimally into focus. This system allows inspection of objects at different height levels such as sandwiched PCB’s, tall components or positional measurement of tall connector pins.
An autofocus system can adjust focus automatically if height variations are caused by different PCB heights or warped PCB’s. Inspection of PCB’s inside carrying jigs can be easily brought to optimal inspection heights without the need to accurately optimize custom-made jigs for the AOI system.
AOI systems equipped with side cameras benefit further from a motorised Z axis. Due to the angled view on objects, the inspection position in the FoV (Field of View) depends on the vertical position of the object to be inspected. If the vertical position changes, e.g. due to varying PCB thicknesses, PCB warpage or differing component heights, the inspection location would need to be adapted accordingly. The motorised Z axis compensates for the change in position automatically, without the need to adjust the inspection programs.
• Motorised Z-axis for inspection at different vertical levels
• Manual focus for inspection of sandwich assemblies
• Autofocus for automatic height adjustment on specific regions of interest
• Vertical adjustment range up to 60mm depending on model
• Smooth repositioning of side camera inspection frames when vertical position changes