Lead-free optical glasses with a hard flint position

US7501366B2 · kind B2 · utility

Assignee

• Schott AG · DE

Inventors

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

Key dates

• Filing date: Mar 16, 2007
• Grant date: Mar 10, 2009
• Expiry date: Mar 16, 2027

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S501/901
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

Optical glasses are described, which are useful for imaging, sensors, microscopy, medical technology, digital protection, photolithography, laser technology, wafer/chip technology, as well as telecommunication, optical communications engineering and optics/lighting in the automotive sector, with a refractive index of 1.80≦nd≦1.95 and an Abbe value from 19≦νd≦28 with excellent chemical resistance and stability to crystallization. These optical glasses have a composition, in weight. % based on oxide content, of: P2O5, 14-35; Nb2O5, 45-50; Li2O, 0-4; Na2O, 0-4; K2O, 0.5-5; BaO, 17-23; ZnO, 0.1-5; TiO2, 1-<5; ZrO2, 0-6; and Sb2O3, 0.1-2.