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:
Jun. 13, 1995
Filed:
Jun. 10, 1994
Reinhard Kassner, Alfeld, DE;
Deutsche Spezialglas AG, Grunenplan, DE;
Abstract
A high-refractive index phototropic glass having a refractive index of 1.69 to more than 1.7, an Abbe coefficient of at least 35 and a density of at most 3.5 g/cm.sup.3, has a composition (in % by weight based on oxide) of: SiO.sub.2 15-33; B.sub.2 O.sub.3 12-22; .SIGMA. SiO.sub.2 +B.sub.2 O.sub.3 30-50; Li.sub.2 O 0.5-5.0; Na.sub.2 O 0-3; K.sub.2 O 0-11; .SIGMA. alkali oxides 4-12; BaO 0-23; SrO 0-23; .SIGMA. SrO+BaO 0-23; ZrO.sub.2 5-14; Nb.sub.2 O.sub.5 15-24; Ta.sub.2 O.sub.5 2-11. As the carrier of the phototropism, the glass also has 0.10 to 0.35 of Ag.sub.2 O; 0.15-0.65 of Cl; 0.15-0.45 of Br and 0.005-0.030 of CuO. The glass can also be doped with 1-3 ppm of gold or one or more platinum metals, especially palladium.