Triangulation sensors for process control and reverse CAD

The author discusses the unique requirements of two triangulation applications and how sensors can be designed to overcome the problems associated with these requirements. The first application is in-process inspection of surface mount electronic components and assemblies. The second application is reverse CAD, wherein the shapes of unknown objects are digitized and entered into CAD databases. For both these applications the effect of the application requirements on the design of the sensor optics, data interpretation, and control system is considered. It is shown that general triangulation principles can be applied to specific design problems. Data from both these applications are presented