Comparison of reference laser interferometer systems

Progress Report, 6 October 2005

After the first comparison of OMH reference laser interferometer in CMI in October 2001 there was a delay in the project and CMI laboratory was reconstructed.

The next set of measurement was made in October 2005 when BEV and JV interferometers were compared with CMI. The agreement of measured displacements was better that stated uncertainties. We have exchanged the experiences with counting interferometers, which will greatly reduce the risk of fault in future.

The detailed results will be presented at EUROMET TC L meeting.


Laser interferometers play significant role in the traceability dissemination from primary length standards into the large area of measurements in technical praxis. Therefor the verification for not only frequency and ambient condition monitoring system, but together with that for complex measuring function as well is recommended these days. CMI has been providing the complex metrological verification of LI system using its own developed reference IK-1 interferometrical comparator for many years.

In the CMI in the laboratory for interferometrical measurements will be compared reference LI systems of all the participants for theirs complex measuring function.

Length (L)
Coordinating Institute
CMI (Czech Republic)