NONLINEAR REFRACTIVE INDEX MEASURING METHOD AND DEVICE FOR SINGLE MODE OPTICAL FIBER

摘要

PROBLEM TO BE SOLVED: To measure a nonlinear refractive index of the single mode optical fiber by correcting the influence of a chirp of a light pulse used for measurement. SOLUTION: The spectral band width of an output light pulse of a measured optical fiber with respect to each input power is measured, the spectral spread of the spectral band width with respect to the input spectral band width is calculated, and the nonlinear refractive index n2 ' of the measured optical fiber is obtained from the gradient of a straight line produced when the spectral spread becomes a linear function of the input power. The correction coefficientξexpressed as a function of a chirp coefficient C is found by numerical calculation, and the nonlinear refractive index n2 ' obtained by the measurement is multiplied by the correction coefficientξ, so that a nonlinear refractive index n2 corrected the influence of the chirp of the input light pulse is calculated.