| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical amplifier for optical packet communication having excellent characteristics, where transient response is suppressed, even if traffic and rare-earth-doped fiber are small.SOLUTION: In an optical amplifier for optical packet communication using a rare-earth-doped fiber, the rare-earth-doped fiber has a diameter of 3.4 μm or more and 10 μm or less in an active region. In the optical amplifier, the non-saturation region is expanded in the amplifier operation, by reducing the numerical aperture so that the integral value of erbium ion and the mode field of light decreases in a duplicate region. The numerical aperture of the rare-earth-doped fiber is 0.2 or less, and the length of the rare-earth-doped fiber is 1-4 m. |
