Glass sheet with high near-IR transmission and very low visible transmission

US12234180B2 · kind B2 · utility

Assignee

• AGC GLASS EUROPE · BE

Inventors

• Michel Bogaerts · Braine-le-Château, BE
• Yannick SARTENAER · Vedrin, BE
• Francois Boland · Gembloux, BE

Key dates

• Filing date: Aug 28, 2019
• Grant date: Feb 25, 2025
• Expiry date: Dec 18, 2041

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C03C4/10
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A silicate-type glass sheet that includes 0.002-1.1% total iron (expressed as Fe2O3), greater than or equal to 0.005% manganese (expressed as MnO), and optionally 0-1.3% chromium (expressed as Cr2O3). The sum of the contents of total iron, manganese, and chromium, expressed as weight percentages are greater than or equal to 1% of the total weight of the glass. The ratios R1, defined as Fe2O3*/(49+0.43(Cr2O3*—MnO*)), and R2, defined as Fe2O3*/(34+0.3(Cr2O3*—MnO*)), both being less than 1. Fe2O3*, MnO* and Cr2O3* represent the relative percentages with respect to the sum of (Fe2O3+MnO+Cr2O3). Such a glass sheet shows a very low visible transmission together with high IR transmission in the region 1000-2000 nm, especially at wavelengths of interest between 1050 and 1550 nm, thereby valuable within the context of autonomous cars, in particular those fully integrating LiDAR systems.