Aluminoborosilicate glass and method for the production of crystallite-free gradient index lenses

US7482296B2 · kind B2 · utility

Assignee

• GRINTECH GmbH · DE

Inventors

• Bernhard Messerschmidt · Jena, DE
• Christian Ruessel · Jena, DE
• Sandra Hornschuh · Torgau, DE
• Torsten Possner · Jena, DE
• Ulf Possner · Jena, DE

Key dates

• Filing date: Dec 17, 2004
• Grant date: Jan 27, 2009
• Expiry date: Jul 10, 2026

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C03C21/005
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

The invention is directed to an aluminoborosilicate glass containing alkali metals for the production of optical components with refractive index gradients which are generated by ion exchange of monovalent metal ions in a base glass comprising at least silicon oxide, boron oxide, aluminum oxide and an alkali metal oxide, particularly for the production of gradient index lenses (GRIN lenses). The object of the invention, to find a novel possibility for producing GRIN lenses based on aluminoborosilicate glasses in which the glass has an appreciably reduced tendency toward crystallization in subsequent thermal treatment processes, is met according to the invention in an alkali-containing aluminoborosilicate glass for the production of optical components with refractive index gradients generated by ion exchange of monovalent, refractive index-changing metal ions in a base glass of SiO2, Al2O3, a metal-(III)-oxide (of B and/or Ga) and at least one metal-(I)-oxide (of Li, Na, K and/or Rb) in that defined molar ratios of metal-(III)-oxides to the metal-(I)-oxides of the base glass are adjusted within a given range in order to appreciably reduce the tendency toward crystallization of the g…