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:
Jan. 02, 2007
Filed:
Dec. 24, 2003
Yoshiko Kasuga, Tokyo, JP;
Xuelu Zou, Tokyo, JP;
Yoshiko Kasuga, Tokyo, JP;
Xuelu Zou, Tokyo, JP;
Hoya Corporation, Tokyo, JP;
Abstract
An optical glass being free of lead and fluorine, having a low glass transition temperature permitting press-molding with a mold formed of stainless steel and having high climate resistance includes an optical glass comprising, by mol %, 25 to 44% of PO, 10 to 40% of a total of LiO, NaO and KO, 5 to 40% of ZnO, 1 to 35% of BaO and at least one components selected from NbO, BiOand WO, having a glass transition temperature (Tg) of 370° C. or lower and being free of lead and fluorine and an optical glass which is free of lead and fluorine, has a mass loss ratio of less than 0.25% when immersed in pure water, and has a glass transition temperature (Tg) of 370° C. or lower.