OPTICAL FIBER

摘要

An optical fiber is composed of a clad part substantially made of pure quartz and a core part which is surrounded by the clad part and has a higher refraction index than the clad part. A relative refractive index difference at the center of the core part is 0.15-0.30[%], and the maximum relative refractive index difference of the core part is 0.4-0.6[%]. The relative refractive index difference at the core part is preferably 0.30-0.40[%] in average. A mode field diameter at 1310nm can be 8.6-9.5µm, and a cable cut off wavelength can be 1260nm or less. Furthermore, a loss at 1383nm after hydrogen aging is preferably 0.4[dB/km] or less.