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Comparison of Optical-Power Meters Between the NIST and the PTB



Igor Vayshenker, Holger Haars, John H. Lehman, David J. Livigni


We describe the results of a comparison of optical-power meters undertaken by the National Institute of Standards and Technology (NIST, USA) and the Physikalisch-Technische Bundesanstalt (PTB, Germany) at nominal wavelengths of 1300 nm and 1550 nm. Both laboratories used thermal detectors as reference standards, which were compared using a germanium trap detector as a transfer standard. Measurement results showed differences of less than 1 part in 103, well within the combined uncertainty for both laboratories.


calibration, cryogenic radiometer, international comparison, optical power meter, optical power uncertainty


Vayshenker, I. , Haars, H. , Lehman, J. and Livigni, D. (2000), Comparison of Optical-Power Meters Between the NIST and the PTB, Metrologia, [online], (Accessed April 21, 2024)
Created September 30, 2000, Updated October 12, 2021