Patent ID: 6333288
Filing Date: 2001-12-25
Classification: C03C,Y10S

Abstract:
An essentially lead-free or lead-free optical glass having a refractive index n.sub.d of from 1.65 to 1.87 and an Abbe number .nu..sub.d of from 27 to 43, and comprising in % by weight, based on oxide:SiO.sub.2 10-25 B.sub.2 O.sub.3 .gtoreq.10-25 Na.sub.2 O 2.5-10 K.sub.2 O 0-3 CaO 0.5-5 BaO 15-30 ZnO 5-15 TiO.sub.2 6-15 ZrO.sub.2 0.5-8 Y.sub.2 O.sub.3 0.1-2 La.sub.2 O.sub.3 0.5-8 Nb.sub.2 O.sub.5 6-12 with La.sub.2 O.sub.3 + Nb.sub.2 O.sub.5 .ltoreq.17 Ta.sub.2 O.sub.5 0-1 Gd.sub.2 O.sub.3 0-1and optionally a fining agent.