METHOD OF MANUFACTURING FIBER GRATING, SUPERSTRUCTURE LONG PERIOD FIBER GRATING AND GAIN EQUALIZER

摘要

PROBLEM TO BE SOLVED: To solve a problem that a gain equalizer of transmission loss-spectra with a narrow band can not be miniaturized.;SOLUTION: A super structure long period fiber grating is developed in which a plurality of gratings having a length of L1 and the same structure are formed via the parts having a length of L2 in which the grating is not formed, and long period fiber gratings are provided in the parts in which the gratings are not formed, thus a miniaturized gain equalizer having the transmission loss-spectra with a narrow band is provided. Further, by controlling a pre-annealing step for removing hydrogen included in an optical fiber, the variation in the central wavelength of the fiber gratings between the time after ultraviolet ray irradiation and the time after annealing is sufficiently suppressed.;COPYRIGHT: (C)2008,JPO&INPIT