The white light interferometry measurement principle compares the path length of the light                 reflected or scattered by the object surface with a reference path length. In this patented                 measurement process, the measuring head scans the object while moving in the z-direction.
                The results is a 'depth image' of the object with a very low measurement uncertainty. It                 combines the advantages of common tactile sensors with the benefits of optical sensors: high                 measurement accuracy and non-contact, high-speed scanning with a high data rate.