Patent ID: 7003202

Claim:
A measurement method comprising the steps of: generating pulsed probe light linearly polarized, and pulsed pump light that is different in wavelength from said probe light but has the same polarization state; causing said probe light and said pump light to enter an optical fiber to be measured; measuring power oscillation of back-scattered light of said probe light caused by Rayleigh scattering, or power oscillation of back-scattered light of idler light caused by nonlinear effects generated within said optical fiber; obtaining an instantaneous frequency of the measured power oscillation; obtaining dependency of said instantaneous frequency relative to the power oscillation of said pump light in a longitudinal direction of said optical fiber; obtaining a rate of change in said longitudinal direction between phase-mismatching conditions and nonlinear coefficient of said optical fiber, from the dependency of said instantaneous frequency; and simultaneously specifying distributions in said longitudinal direction of the wavelength dispersion and nonlinear coefficient of said optical fiber, based on the rate of change.