Optical glass, method of making the optical glass, optical elements made with the optical glass and uses thereof

US8168553B2 · kind B2 · utility

Assignee

• Schott AG · DE

Inventors

• Silke Wolff · Hückeswagen, DE
• Stefanie Hansen · Gensingen, DE
• Ute Woelfel · Bingen, DE

Key dates

• Filing date: Feb 25, 2010
• Grant date: May 1, 2012
• Expiry date: Apr 26, 2030

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C03C3/253
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

The lead- and arsenic-free optical glass has a refractive index nd of 1.55≦nd≦1.64, an Abbe number νd of 42≦νd≦65, and a low transition temperature Tg≦460° C., good producibility and processability, and crystallization stability. The optical glass has a composition within the following range, in wt. % based on oxide content:The glass may also have a total content of SiO2, B2O3 and Al2O3 that is less than 9 wt. %. The glass may contain MgO, SrO, CaO and BaO, but the sum of these oxides is preferably at least 2 wt. % and at most 12 wt. %. The glass may contain at most 5 wt. % of each of La2O3, TiO2, Nb2O5, at most 2 wt. % Ta2O5 and less than 1 wt. % fluorine.