In industrial manufacturing, compliance with specified tolerances needs to be checked as often as possible so that faulty parts are eliminated before any further processing steps are taken. Proper implementation of this inspection step avoids additional manufacturing costs on an already defective part. With white light interferometers, a large area containing many different structures and surfaces can be examined quickly and checked for defects such as incorrect curvatures, ejecta, and missing connections or dropouts. In many cases, the entire topography of a workpiece or object must be checked - the inspection of the shock absorber component shown above required full topographical analysis prior to certification.
Flatness deviations were measured on the annular surface of a piezo actuator. The results are displayed as a false color plot and a topographical cross section.
In the case of printed circuit boards for surface mount devices (SMD), the height of the solder bumps is of great importance and the surfaces of components must be at a certain angle to each other. These bumps must be measured quickly across a large surface area right after creation and before assembly, without any cooling off time.