OPTICAL FIBER AMPLIFIER WITH HIGH OUTPUT EFFICIENCY IN CONVERSION

PROBLEM TO BE SOLVED: To realize 1,580 nm band optical amplifier with high output conversion efficiency, by connecting C-band and L-band silica-substrate erbium ion doped optical fiber amplifiers (EDFAs) in parallel, and reusing a rear amplified spontaneously emitted light from the C-band or L-band EDFA unit as a secondary pumping light for amplification in the L-band EDFA unit. SOLUTION: A rear amplified spontaneous emissited light beam, generated from C-band and L-band erbium ion doped optical fiber amplifier(EDFA) units 110 and 120 is output and is reused in the L-band EDFA unit 120. As a result of test for the performance characteristics for the optical amplifier, it is certified that efficiency in the output conversion of the system as a whole is increased markedly, when pumping is carried out with a light of 980 nm wavelength. As a result, a loss in low-noise characteristics is reduced, and the an optical amplifier with drastically improved performance can be realized.