ZERO-DISPERSION WAVELENGTH MEASURING METHOD FOR OPTICAL FIBER

摘要

PURPOSE:To obtain a high-accuracy measurement result by making light which has a continuous wavelength spectrum and is intense enough to generate nonlinear optical effect in an optical fiber incident onto an optical fiber to be measured from its one end. CONSTITUTION:Light pulses oscillated by a Nd.YAG laser 10 are made incident on one end of the optical fiber 11 and inductive Raman scattering is caused while the pulses are propagated in the optical fiber 11, thereby obtaining light pulses having the continuous wavelength spectrum. Then the projection light from the other end of the fiber 11 is made incident on one end of the optical fiber 12 to be measured, nonlinear optical effect, etc., is caused by this fiber 12, and the light is projected from the other end on a spectroscope 13 controlled by a control part 15. The projection light of this fiber 12 has its wavelength spectrum measured from the relation between the indication wavelength of the spectroscope 13 and the output of a photodetector 14. The wavelength with which the intensity decreases greatly as compared with other wavelength components with respect to the wavelength spectrum of the projection light is selected as the zero-dispersion wavelength of the fiber 11.