| 摘要 |
PURPOSE:To easily separate multiplexed signal light with simple constitution by providing an optical branch part which performs power coupling between optical fibers for amplification differing in amplification band, and exciting light and the signal light and also provides power branching to the fiber. CONSTITUTION:This device guides the exciting light from, for example, a laser device 3 oscillating with specific wavelength to an optical fiber and the optical branch part 4 multiplexes the signal light propagated in an optical fiber 1 and the exciting light propagated in the fiber 2 and branches the multiplexed light into N spatially. The branch part 4 is composed of an optical fiber multiplexer demultiplexer composed of a star coupler having, for example, plural input/ output ports Pi and Po, and the signal light and exciting light are made incident from two optional ports on an input side. Further, the optical fibers 5 for amplification are connected to N output parts of the branch part 4 respectively and formed by adding a rare earth element the cores of, for example, SiO2-based optical fibers to specific density. |
