Optical and ophthalmic glasses
US4742028A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 20, 1986 |
| Grant date | May 3, 1988 |
| Priority date | — |
| Expiry date | Jun 20, 2006 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S501/903
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
This invention is concerned with a glass for optical and/or ophthalmic applications having an index of refraction between about 1.78-1.82, an Abbe number greater or equal to 31, and a density less than about 3.80 g/cm.sup.3 consisting essentially, expressed in terms of weight percent on the oxide basis, of: ______________________________________ SiO.sub.2 15-30 CaO 15-28 B.sub.2 O.sub.3 2-17 SrO 0-11 SiO.sub.2 + B.sub.2 O.sub.3 24-36 BaO 0-11 Al.sub.2 O.sub.3 0-6.5 MgO + CaO + 16-33 SrO + BaO Li.sub.2 O 0-5 ZnO 0-11 Na.sub.2 O 0-5 La.sub.2 O.sub.3 16-30 K.sub.2 O 0-5 ZrO.sub.2 0-10 Li.sub.2 O + Na.sub.2 O + K.sub.2 O 0-6 Nb.sub.2 O.sub.5 5-26 MgO 0-6 TiO.sub.2 0-14. ______________________________________
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.