摘要 |
PROBLEM TO BE SOLVED: To obtain an optical fiber capable of realizing the wide expansion of a band zone, a high profit and a large length by disposing a core comprising a SiO2 glass containing Er, Al and Te and a cladding comprising a polymer material covering the outer circumference of the core. SOLUTION: This rare earth element-added optical fiber comprises (a) a core 1 comprising SiO2 glass containing Er preferably in an amount of 100-2000 wt.ppm, Al preferably in an amount of 1000 wt.ppm to 6 wt.%, and Te preferably in an amount of 1 wt.% to ten and several wt.%, and a polymer cladding 2 comprising a polymer material (e.g. a silicone resin, polyvinylidene fluoride or the like) covering the outer circumference of the core 1. The optical fiber also comprises (b) a core 1 comprising SiO2 glass containing Er, Al and <=5 wt.% of Te and a clad layer 2 covering the outer circumference of the core 1. The SiO2 glass is preferably SiO2 glass or the SiO2 glass containing one or more of P2 O5 , B2 O3 and F. |