| 摘要 |
PURPOSE:To provide a high-efficiency and highly reliable optical fiber amplifier capable of feeding sufficient excitation light to a rare earth-doped fiber in a low injection current compared to the conventional constitution of the optical fiber amplifier. CONSTITUTION:A fiber coupler 4 is connected with an Er-doped fiber 1 and an optical filter 6, which absorbs light of the same wavelength range as that of amplified spontaneous emitted light generated in the fiber 1 or makes the light reflect, is provided in a port on the side, whereon excitation light is incident, of the coupler 4. |
