Calibration and traceability
LDV probes can be calibrated by specifying very constant velocities due to the direct proportionality of velocity and signal frequency. The proportionality constant corresponds to the distance between the interference fringes.
For the realisation of the velocities, rotating discs with an exactly known diameter ("turntable" principle), on which a few particles in the micrometre range are applied, are usually used. The signal frequency is recorded with high precision using signal processing typical of LDV.
In addition, the LDV signal processing chain (hardware and software) can be electrically calibrated by specification and comparison with known frequencies.
The calibrations of LDV probe and LDV signal processing are possible according to DIN ISO/IEC 17025:2028 or according to factory standard.