Optical glass and its use
US6251813A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 27, 1999 |
| Grant date | Jun 26, 2001 |
| Priority date | — |
| Expiry date | Apr 27, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S501/903
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
An optical glass having properties of a high refractive index and low dispersion and having both a low sag temperature T.sub.s and a low liquidus temperature L.T., is provided. The optical glass comprises, by % by weight, 25 to 42% of B.sub.2 O.sub.3, 14 to 30% of La.sub.2 O.sub.3, 2 to 13% of Y.sub.2 O.sub.3, 2 to 20 of SiO.sub.2, greater than 2% and 9% or less of Li.sub.2 O, 0.5 to 20% of CaO, 2 to 20% of ZnO, 0 to 8% of Gd.sub.2 O.sub.3, 0 to 8% of ZrO.sub.2, Gd.sub.2 O.sub.3 +ZrO.sub.2 being 0.5 to 12%, the total content thereof being at least 90%, and optionally contains 0 to 5% of Na.sub.2 O, 0 to 5% of K.sub.2 O, 0 to 5% of MgO, 0 to 5% of SrO, 0 to 10% of SrO, 0 to 10% of BaO, 0 to 5% of Ta.sub.2 O, 0 to 5% of Al.sub.2 O.sub.3, 0 to 5% of Yb.sub.2 O.sub.3, 0 to 5% of Nb.sub.2 O.sub.5, 0 to 2% of As.sub.2 O.sub.3 and 0 to 2% of Sb.sub.2 O.sub.3.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.