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. 04, 1997
Filed:
Oct. 06, 1995
Applicant:
Inventor:
Masahiro Onozawa, Sagamihara, JP;
Assignee:
Kabushiki Kaisya Ohara, , JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C03C / ;
U.S. Cl.
CPC ...
501 73 ; 501 47 ; 501 48 ; 501 77 ; 501 79 ; 501903 ;
Abstract
An optical glass having optical constants of a refractive index (Nd) from 1.50 to 1.60 and an Abbe number (.nu.d) ranging from 62 to 73, a transformation temperature (Tg) of 550.degree. C. or below, and barely cracks or sticks to metal molds when the glass is subjected to mold pressing, maintains excellent chemical durability, and having softening capability at a low temperature which can be obtained by restricting the composition of the glass in weight percents within a specific range of a SiO.sub.2 --Al.sub.2 O.sub.3 --P.sub.2 O.sub.5 --R.sub.2 O system.