| 摘要 |
PROBLEM TO BE SOLVED: To improve excitation efficiency, to make an exciting light source operative with a low driving current and to improve reliability by connecting the exciting light which is heretofore not used in two stages of optical fiber amplifiers via optical multiplexer/demultiplexers. SOLUTION: This device is constituted by connecting two units of the optical fiber amplifiers 1, 11 in series. The amplifier 1 is composed of an erbium-doped optical fiber 2, the fiber fusion type optical multiplexer/demultiplexers 3, 4, a 1.48μm exciting LD module 5 and a polarization independent type inline optical isolator 6. The amplifier 11 is composed of the erbium-doped optical fiber 12, fiber fusion type optical multiplexer/demultiplexers 13, 14, the 1.48μm exciting LD module 15 and the polarization independent type inline optical isolators 16, 17. The exciting light which heretofore not used is reutilized with the device, by which the exciting light power of, for example, 70mW, 60mW (total 130mW) is made sufficient and the considerable improvement in the efficiency is attained. |
