| 摘要 |
PURPOSE:To enable long-distance transmission by arranging a fiber for transmission which is small in Brillouin gain on the side of a light signal part where high light signal electric power is made incident. CONSTITUTION:The transmission line for long-distance transmission is constituted by connecting the optical fiber 3 which is small, specially, in Brillouin gain to an optical transmission part 1 in an optical fiber for transmission. Namely, the fiber 3 such as a 1.3mum zero-dispersion fiber (what is called a pure quartz core fiber) which is large in the threshold value of backward inductive Brillouin scatter among fibers for current transmission is arranged in the transmission line on the incidence side first and high incident photoelectric power is propagated in this fiber 3, attenuated, and then connected to a trailing fiber 4 to constitute the long-distance transmission line which evades an input limit. Consequently, the high light signal electric power is propagated efficiently in the transmission line to constitute the long-distance transmission line. |
