Patent ID: 6196684
Filing Date: 2001-03-06
Classification: C03C,Y10S

Abstract:
Glass having a refractive index in the range of 1.70-1.78 and having compositions expressed in percentages by weight on an oxide basis, that consist essentially of:SiO.sub.2 27-36 B.sub.2 O.sub.3 0-9 Li.sub.2 O 1-5 Na.sub.2 O 1-7 K.sub.2 O 0-7 CaO 0-7 BaO 4-13 ZnO 0-8 La.sub.2 O.sub.3 4-15 PbO 4-27 TiO.sub.2 7-18 ZrO.sub.2 0-9 Nb.sub.2 O.sub.5 0-8 with: Li.sub.2 O + Na.sub.2 O + K.sub.2 O 6-15 SiO.sub.2 + TiO.sub.2 + ZrO.sub.2 42-55 PbO + TiO.sub.2 + ZrO.sub.2 + Nb.sub.2 O.sub.5 29-40