Measurement method of resonant nonlinearity in the nonlinear optical fiber using a long period fiber grating pair

摘要

PURPOSE: A method for measuring the resonant nonlinearity using a pair of long-period optical fiber gratings is provided to improve the accuracy of measurement by reducing the thermal effect due to a pumping beam of an optical fiber. CONSTITUTION: A nonlinear optical fiber(20) is connected between a pair of first and second long-period optical fiber gratings(10a,10b). A pumping light(30) and a light(40) are simultaneously incident into the first or second long-period optical fiber grating(10a,10b). The pumping light(30) generates the resonant nonlinearity. A spectrum analyzer(60) measures the nonlinearity of the light(40) by using variation of an interference pattern created by the first and second long-period optical fiber grating(10a,10b).