Method of and apparatus for multi-image inspection of bonding wire

摘要

An optical system of inspecting bonding wires on a semiconductor by using a camera, focal length and depth adjusting unit, and an illumination device for irradiating brilliantly a desired portion of an inspection object with an illumination light. The focal length and depth adjusting means comprises a plurality of glass plates each having a different focal length and depth, and each bonding wire is inspected at a plurality of levels at a height position of the wire and at a plurality of portions thereof in its longitudinal direction to make a comparison between focal point evaluation quantities or feature quantities at each detected position so that wiring defects can be detected.