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. 19, 2006
Filed:
Oct. 29, 2002
Masaaki Otsuka, Saitama, JP;
Naruhito Sawanobori, Saitama, JP;
Shinobu Nagahama, Saitama, JP;
Sumita Optical Glass, Inc., Saitama, JP;
Abstract
An optical glass suitable for mold forming having a metal composition in wt % in terms of metal oxides calculated from the composition of the following components: PO34–50%, LiO 2–9%, NaO 7–28%, KO 3–27%, provided that the total of RO is 17–41% (R: Li, Na, K), AlO6.5–30%, ZnO 0–22%, BaO 0–21%, SrO 0–18%, CaO 0–16%, MgO 0–14%, provided that the total of R'O is 0–34% (R′: Zn, Ba, Sr, Ca, Mg), ZrO0–1.5% and F 1.5–32% relative to the total weight of the oxides, and exhibits a glass transition temperature (Tg) of 350° C. or lower and a specific gravity (Sg) of 3.1 or less and is excellent in chemical durability. The optical glass can be press formed at a low temperature of about 270 to 400° C.