GLASS FOR FIBER IN LIGHT GUIDE

摘要

A glass for a light guide fiber GA1 is used in a core of a fiber 10 of a light guide, and has a refractive index nd between 1.56 and 1.74. The glass for a light guide fiber GA1 has the following composition: (A) SiO 2 : 20 to 55 wt%, (B1) B 2 O 3 : 0 to 4.0 wt%, (B2) does not contain P 2 O 5 and GeO 2 , (C) (BaO+SrO+La 2 O 3 +Lu 2 O 3 +Ta 2 O 3 +Gd 2 O 3 +WO 3 ): 25 to 72 wt%, (D) ZnO: 0 to 30 wt%, (E) does not contain Al 2 O 3 , (F) does not contain ZrO 2 , (G) does not contain PbO and As 2 O 3 , (H) (Na 2 O+K 2 O): 0 to 15 wt%, (1) Sb 2 O 3 0 to 0.050 wt%, and (J) (Na 2 SO 4 +K 2 SO 4 ): 0.26 to 1.63 wt%.