Lead-free and preferably arsenic-free lanthanum heavy flint glass
US7091145B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 16, 2003 |
| Grant date | Aug 15, 2006 |
| Priority date | — |
| Expiry date | Jan 3, 2024 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03C3/068
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The lead-free and arsenic-free optical glass has a refractive index nd of 1.84≦nd≦1.96 and an Abbé number νd of 27≦νd≦36, with good chemical resistance, excellent crystallization resistance and the following composition (in % by weight based on oxide): SiO2, 1 to 8, B2O3, 13 to 19.5, La2O3, 34 to 50; MgO, 0 to 6, CaO, 0 to 6, BaO, 0 to 6, ZnO, 0 to 9 with ΣMO, 1 to 10; and TiO2, 4 to 15, ZrO2, 0 to 11, Nb2O5, 6 to 14.5. In addition, the glass according to the invention, as well as having a maximum alkali metal oxide content of 10% by weight, may also contain standard refining agents other than arsenic. The glass according to the invention is used in imaging, projection, telecommunications, optical communication and/or laser technology.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.