Radiation-Resistant Single-Mode Optical Fibers

Loss of silica-based optical fibers increases when they are exposed to radiation. We have developed a fluorine-doped core single-mode optical fiber, which complies with ITU-T G.652.B and has excellent radiation-resistant characteristics compared with pure silica core singlemode fiber. Although the increase in radiation-induced loss of the conventional pure silica core single-mode fibers with the condition 1 · 10 6 R/h and 60 min is approximately 25 dB/km at 1310 nm wavelength, the loss of the fluorine-doped core single-mode fibers with the same condition is approximately 5 dB/km at 1310 nm wavelength. In addition to the excellent radiationresistant characteristics, we have confirmed that the fiber has an excellent loss recovery characteristic after irradiation.