Optical high-power nonlinearity comparison between the National Institute of Standards and Technology and the National Metrology Institute of Japan at 1480 nm.

We compare the results of measurements of the nonlinearity of high-power optical fiber powermeters (OFPMs) by two national metrology institutes (NMIs): the National Institute of Standards and Technology (NIST-USA) and the National Metrology Institute of Japan/National Institute of Advanced Industrial Science and Technology (NMIJ/AIST-Japan) at a wavelength of 1480 nm. The nonlinearity and range discontinuity of a commercial OFPM were measured from 1 mW to 500 mW by use of a superposition method (both laboratories) and from 1 mW to 250 mW by use of a comparison method (NMIJ only). Measurement results showed largest differences of less than 1.6 parts in 10(3), which is within the combined expanded (k = 2) uncertainty for both laboratories.