White light interferometer

A less frequently used method in coordinate metrology is white light interferometry. In this method, a white light interferometer is moved along the optical axis. For each position of the sensor, a special interference method is used to determine the object points that are located at a predefined distance from the sensor[1]. There are point-shaped and planar white light interferometers. With the latter, the points can be determined during movement – similar to the 3D patch – for different sectional planes and then combined to form a point cloud. This describes the surface topography of the workpiece in three dimensions. The results depend relatively heavily on the surface properties (reflection behaviour) of the measuring objects.