Scaling a 3D vision system from automobiles down to circuit board inspection: issues in small field of view inspection

摘要

A look at the challenges surrounding the modification of a large field of view system (6"-18") for small field of view (approx0.5") inspection in the electronics industry. Camera-based 3D systems suffer serious losses in depth of field when attempting to look at small fields of view. Off axis lens placement and careful application of the Scheimpflug Rule can significantly improve any camera-based inspection system, but these improvements may require modifications in your camera calibration procedures. A manufacturing inspection application and the improvements brought about by these techniques are discussed along with the pitfalls that were encountered along the way.