Dimensional metrology dealing with objects in the micro- and nanoworld relies predominantly on AFM (Atomic Force Microscope) and related local probe microscopy techniques where the object topology, dimensions and other properties are examined by scanning the sample. Positioning of the probe in AFM microscopes through piezoelectric (PZT) transducers offers sub-nm resolution but small range over several tens of micrometers. More, PZT transducers suffer errors of repeatability, non-linearity and hysteresis. Metrological AFM can be calibrated using etalon gratings or samples of height staircase type in the scale of hundreds or thousands of nanometers.