METHOD OF MEASURING RAMAN GAIN COEFFICIENT

摘要

PROBLEM TO BE SOLVED: To provide a method for precisely measuring the Raman gain coefficient of a measured optical fiber. SOLUTION: In this Raman gain coefficient measuring method, a condition Pin>100.NFnet.h.ν.Δνis made to be satisfied for the optical density Pin of test light incident on the measured optical fiber 2, where NFnet is the noise figure of the optical fiber 2,νis the measuring frequency of an optical spectrun analyzer 50,Δνis measuring resolution, and h is the Plank's constant, and a condition ofΔG/Gpeak<1.7% is made to be satisfied, where Gpeak is the peak value of the Raman gain of the optical fiber 2, andΔG is the deviation, of the Raman gain of the optical fiber 2, between two wave lengths (on condition that a wave length interval is from 20 nm or more to 30 nm or less, and the maximum wave length interval) where the Raman gain gets equal, to measure the Raman gain coefficient of the measured optical fiber 2.