| 摘要 |
PURPOSE:To easily execute optical coupling at the time of synthesizing or branching signal light and to reduce the generation of loss due to the coupling by arranging an optical synthesizer and an optical branching unit before and after the stage of two optical amplifiers. CONSTITUTION:Light beams inputted to two input ports of a 3dB fiber coupler 43 are synthesized by the coupler 43 and then branched to two beams, which are outputted from respective output ports. The two branched beams are respectively inputted to individual optical amplifiers 41, 42 and directly amplified. Respective output beams from the amplifiers 41, 42 are individually inputted to two input ports of a 3dB fiber coupler 44, synthesized and then branched to two signal beams, which are outputted from respective output ports. Consequently, optical coupling can easily be executed at the time of synthesizing or branching signal beams and the coupling loss can be reduced. |
