Optical glass with negative anomalous partial dispersion

US5100843A · kind A · utility

Assignee

• Schott Glaswerke · DE

Inventors

• Danuta Grabowski · Wiesbaden, DE
• Marc Clement · Mainz, DE
• Volkmar Geiler · Ingelheim am Rhein, DE

Key dates

• Filing date: May 31, 1990
• Grant date: Mar 31, 1992
• Expiry date: May 31, 2010

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S501/903
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A glass having a negative anomalous partial dispersion .DELTA.P.sub.g,F, an index of refraction of n.sub.d .gtoreq.1.67 and an Abbe number of .nu..sub.d >36 has the following composition, in % by weight, 3-11 of SiO.sub.2, 0-3 of GeO.sub.2, .SIGMA. SiO.sub.2 +GeO.sub.2, 4.5-11; B.sub.2 O.sub.3, 29-35; 5-13 of Al.sub.2 O.sub.3 ; 1-3 of ZrO.sub.2 ; 0.2-3 of TiO.sub.2 ; 0.2-1.5 of Ta.sub.2 O.sub.5 ; 30-45 of PbO; 0-3 each of Li.sub.2 O, Na.sub.2 O, K.sub.2 O, Rb.sub.2 O, Cs.sub.2 O, .SIGMA. alkali metal oxide 0-3; 0-3.5 each of MgO, CaO, BaO, SrO, .SIGMA. alkaline-earth oxide 0-6, if .SIGMA. SiO.sub.2 and GeO.sub.2 .gtoreq.9; .SIGMA. alkaline-earth oxide 0-3.5, if .SIGMA. SiO.sub.2 and GeO.sub.2 <9; 0-14 of ZnO, 0-3 of La.sub.2 O.sub.3 ; 0-7 of Nb.sub.2 O.sub.3 ; 0-1 of Sb.sub.2 O.sub.3 ; 0-0.3 of As.sub.2 O.sub.3 ; 0-1.5 of WO.sub.3 ; 0-1 of F. This glass is inexpensive and can be produced in high quality, and has a high crystalization stability and good transmission values.