Metrology is the science of measurement and its specificity is not in the measure itself, but in the validation of results.
Optical metrology allows dimensional measurements without contact. It may be a measure of displacement, shape or distance at different scales. In the field of industry, we will deal with scales that correspond to those of mechanics, i.e. from 0.01 micron to a few tens of meters. Metrology occurs throughout the life of a product. It is an indispensable tool at various stages of product development and maintenance.
During the past twenty years, the optical methods of non-contact dimensional measurements have been widely developed in industrial laboratories and societies using measurement tools, thanks to their low cost development. They are widespread in the mechanical field where they are found in the form of simple detector “all or nothing”. For a higher cost, they are encountered in the form of two-dimensional sensors.
The more complex systems allow three-dimensional measures. At the Hololab, we use an interferometric fringe projector, based on the separation of the polarization states of a laser beam, in order to characterize shape. The first aim of this scanner was to be a powerful tool for archeologist. From now on, the purpose of the MINT project is to produce a more automatic system and adapt this system to an industrial environment with limiting factors such as high temperature, vibrations and dust.