In response to these new features, filtration techniques are required to be robust against outliers, applicable to surfaces with complex geometry and reliable in whole range of measurement data. Massive functionally and geometrically complicated surfaces emerge as the output of modern product technologies. Filtration techniques are progressing along with the advancement of manufacturing technology. In such a manner, noises are removed by filters before fitting routines are applied to generate the geometry of the measurand. They also serve in dimensional metrology for data smoothing. For instance, filtration techniques are employed in surface metrology to separate the roughness component from the waviness component and the form component so that suitable characterization parameters can be derived with an aim to control the manufacturing process. It is the means by which the information of interest is extracted from the measured data for further analysis.

Filtration is one of the core elements of analysis tools in geometrical metrology.

Hexagon metrology group