| 摘要 |
PROBLEM TO BE SOLVED: To miniaturize an optical amplifier having the ultrabroad zone of 1.5 to 1.6μm band. SOLUTION: A narrow strip light of 1.55μm and a narrow strip light of 1.58μm are made incident on the part A of a light circulator 12 from an input signal wire 10, and the lights are made incident on an optical amplifier 14 from a part B. The light outputted from the part B of the optical circulator 12 is amplified by the optical amplifier 14, and it is made incident on a reflection filter 18. The reflection filter 18 reflects the 1.55μm strip light and it permeates through the 1.58μm strip light. The 1.55μm strip light reflected by the reflection filter 18 is made incident on the optical amplifier 14. The 1.58μm strip light, which permeated through the reflection filter 18, is amplified by an optical amplifier 20, reflected by a reflection mirror 22, amplified by the optical amplifier 20, and it is made incident on the optical amplifier 14 passing through the reflection filter 18. The 1.55μm strip light, which is made incident on the light amplifier 14, and the 1.59μm strip light are amplified, they are made incident on the part B of the optical circulator 12, and it is outputted to an output signal wire 16 from a part C. |
