Abstract The present invention relates to an optical glass for an optical path, having a refractive index of at least 1.55, an Abbe number of at least 48 and a specific gravity of at most 2.90 and being excellent in chemical durability, having a chemical composition of: ______________________________________ SiO 2 55 to 65% by weight
B 2 O 3 0 to 10
TiO 2 + ZrO 2 1 to 5
TiO 2 0 to 5
ZrO 2 0 to 5
CaO + ZnO 20 to 33
CaO 5 to 20
ZnO 3 to 20
Al 2 O 3 0 to 4
one or more of R 2 O (Li 2 O, Na 2 O, K 2 O)
5 to 9
As 2 O 3 0 to 1
______________________________________
Inventors
👤 Shinobu Tokunaga
👤 Yuichi Shiina
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-11-04 03:24
CPC Classifications
C; C08; C08K; C08K3/00; C08K3/34; C08K3/36
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
100 words
An optical glass for an optical path having a refractive index of at least 1.55, an Abbe number of at least 48 and a specific gravity of at most 2.90, which consists essentially of ______________________________________
SiO.sub.2 55 to 65% by weight
B.sub.2 O.sub.3 0 to 10
TiO.sub.2 + ZrO.sub.2
1 to 5
TiO.sub.2 0 to 5
ZrO.sub.2 0 to 5
CaO + ZnO 20 to 33
CaO 5 to 20
ZnO 3 to 20
Al.sub.2 O.sub.3 0 to 4
at least one of
R.sub.2 O (Li.sub.2 O, Na.sub.2 O, K.sub.2 O)
5 to 9
As.sub.2 O.sub.3 0 to 1
______________________________________
Claim 2
Dependent Claim
100 words
An optical glass for an optical path having a refractive index of at least 1.55, an Abbe number of at least 48 and a specific gravity of at most 2.90, which consists essentially of ______________________________________
SiO.sub.2 55 to 65% by weight
B.sub.2 O.sub.3 0 to 10
TiO.sub.2 + ZrO.sub.2
1 to 5
TiO.sub.2 0 to 5
ZrO.sub.2 0 to 5
CaO + ZnO 20 to 33
CaO 5 to 20
ZnO 3 to 20
Al.sub.2 O.sub.3 0 to 4
at least one of
R.sub.2 O (Li.sub.2 O, Na.sub.2 O, K.sub.2 O)
5 to 9
As.sub.2 O.sub.3 0 to 1
______________________________________