Abstract: A method of and apparatus for detecting flaws on a composite surface laid-up by a fiber placement machine. The invention includes a vision imaging system (78) mounted on the machine so that it has a field of view of the composite tows after they have been compacted by a compaction roller (74). In one embodiment, the visual imaging system (78) includes a laser analog displacement sensor. The imaging system provides a computer analysis system (84) with data regarding the location of the edges of the individual composite tows. The computer imaging system (84) uses the tow edge location data to compute the location and size of gaps or overlaps between the tows or the presence of foreign material. This information is useful in quality control models to evaluate the manufacturing process or final part quality.