OPTICAL AMPLIFIER USING OPTICAL FIBER REFLECTOR

摘要

PURPOSE: An optical fiber amplifier is provided to increase a small signal gain at a long wavelength band(1550nm-1560nm) and reduce the difference in the gain of an optical fiber amplifier in a wider wavelength band(1530nm-1560nm or over). CONSTITUTION: An optical fiber amplifier includes an erbium doped fiber(EDF)(230). A pump laser diode(LD)(220) applies a light for pumping to amplify an incident signal light. A wavelength division multiplexer(WDM) coupler(210) couples the incident signal light and the pump light of the pump LD(220) to transmit the result to the EDF(230). The erbium doped fiber(EDF)(230 amplifies the incident signal light from the WDM coupler(210) using the light for pumping of the pump LD(220) and reversely amplifies the reflection signal light. A circulator(200) allows the incident signal light to be incident to the EDF(230) via the WDM coupler(210) and also outputs the final output light of the reflection signal light reflected from the optical fiber reflector(240), that is, the amplified signal light of the EDF(230). The optical fiber reflector(240) reflects the signal light amplified via the EDF(230) by different reflexibility depending on the wavelengths of the signal light to output the reflection signal light reflected from the optical fiber reflector(240) to the EDF(230).