Dynamic calibration of probes in the μm region with nanometric accuracy

This paper describes a system which enables a traceable dynamic calibration of probes of e.g. roughness testers and roundness testers. The system is based on a Digital Piezo Translator (DPT). For the calibration of the DPT itself, an interferometric technique has been used. After calibration by laser interferometry, the DPT is used as a transfer standard which can be driven by signals of various, but exactly known, form. This time-displacement form can range from square to sinusoidal or quasi-random with a maximum displacement of 15 and a maximum frequency of about 300 Hz. From a practical calibration of a roughness tester it is shown that, depending on the profile, roughness parameters can be measured with an uncertainty ranging from a few nm to 1%