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:
Dec. 28, 2010
Filed:
Feb. 15, 2008
Taro Miyauchi, Tokyo, JP;
Tatsufumi Shiba, Tokyo, JP;
Taro Miyauchi, Tokyo, JP;
Tatsufumi Shiba, Tokyo, JP;
Nippon Sheet Glass Company, Limited, Tokyo, JP;
Abstract
The present invention provides a mother glass composition for gradient-index lens, from which a lead-free Li-based gradient-index lens that is excellent in weather resistance, in particular weather resistance in the presence of water, can be manufactured. The mother glass composition includes the following components, indicated by mol %: 40≦SiO≦65; 1≦TiO≦10; 0.1≦MgO≦22; 0.15≦ZnO≦15; 2≦LiO≦18; 2≦NaO≦20; 0≦BO≦20; 0≦AlO≦10; 0≦KO≦3; 0≦Cs≦O≦3; 0≦YO≦5; 0≦ZrO≦2; 0≦NbO≦5; 0≦InO≦5; 0≦LaO≦5; and 0≦TaO≦5. The mother glass composition further includes at least two oxides selected from CaO, SrO, and BaO each in a range of 0.1 mol % to 15 mol %. The total of MgO+ZnO is greater than or equal to 2 mol %. The molar ratio of ZnO/(MgO+ZnO) is in a range of 0.07 to 0.93. The total of LiO+NaO is in a range of 6 mol % to 38 mol %. The total of YO+ZrO+NbO+InO+LaO+TaOis in a range of 0 mol % to 11 mol %.