The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 31, 1992
Filed:
May. 31, 1990
Schott Glaswerke, Mainz, DE;
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.