GAIN EQUALIZER, LIGHT AMPLIFIER AND OPTICAL COMMUNICATION SYSTEM

摘要

The optical fiber amplifier of this invention is fabricated by using an erbium-doped optical fiber core wire 1 in which a plurality of long-period fiber gratings 21 functioning as a gain equalizer are written in the core with UV laser. Each of the fiber gratings 21 corresponds to periodical modulation of the refractive index within the core caused by irradiating the optical fiber core wire 1 with UV laser through a coat layer. Within the optical fiber core wire 1, the fiber grating 21 compensates and equalizes wavelength dependency of the gain, so as to efficiently realize equal amplification over a wide wavelength band.