US4812423A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical light weight glass
Assignee: Nikon Corp
•
Filing: 1985-07-17
•
Granted: 1989-03-14
•
Expires: 2005-07-17
Abstract
Abstract This specification discloses optical light-weight glass having a composition of SiO 2 47--70, Li 2 O 5.5-21, K 2 O 2-30, Na 2 O 0-30 (Li 2 O+Na 2 O+K 2 O 21-50), TiO 2 9.5-24, B 2 O 3 0-20, CaO 0-20, MgO+SrO+BaO+ZnO 0-4, Al 2 O 3 0-5 and ZrO 2 +La 2 O 3 +Ta 2 O 5 +WO 3 0-3, all being in % by weight, and having a refractive index (n d ) of 1.58-1.65, an Abbe number (γ d ) of 35-50 and a specific gravity of 2.69 or less. This optical glass is light in weight, high in transparency and low in dispersion, and is particularly suitable for spectacle lenses, but can also be utilized for photographic lenses.
Inventors
- 👤 Hiroyuki Kodama
- 👤 Katsumi Mangyo
- 👤 Takeo Ichimura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 20:01
CPC Classifications
C; C03; C03C; C03C3/00; C03C3/04; C03C3/076; C03C3/083; C03C3/085; C03C3/087; C03C3/089; Y; Y10; Y10S; Y10S501/00; Y10S501/90; Y10S501/903
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
86 words
Optical lens of light-weight glass consisting essentially of the following composition in % by weight and having a refractive index (n d ) of 1.58 through 1.65, and Abbe number (ν d ) of 35 through 50 and a specific gravity of 2.69 or less: ______________________________________
SiO.sub.2 47-70
Li.sub.2 O 5.5-21
K.sub.2 O 2-30
Li.sub.2 O + K.sub.2 O
21-50
TiO.sub.2 9.5-24
CaO 0-20
MgO + SrO + BaO + ZnO 0-4
Al.sub.2 O.sub.3 0-5
ZrO.sub.2 + La.sub.2 O.sub.3 + Ta.sub.2 O.sub.5 + WO.sub.3
0-3.
______________________________________
Claim 2
Dependent Claim
86 words
Optical lens of light-weight glass consisting essentially of the following composition in % by weight and having a refractive index (n d ) of 1.58 through 1.65, and Abbe number (ν d ) of 35 through 50 and a specific gravity of 2.69 or less: ______________________________________
SiO.sub.2 47-70
Li.sub.2 O 5.5-21
K.sub.2 O 2-30
Li.sub.2 O + K.sub.2 O
21-50
TiO.sub.2 9.5-24
CaO 0-20
MgO + SrO + BaO + ZnO 0-4
Al.sub.2 O.sub.3 0-5
ZrO.sub.2 + La.sub.2 O.sub.3 + Ta.sub.2 O.sub.5 + WO.sub.3
0-3.
______________________________________
Claim 3
Dependent Claim
52 words
The lens of claim 1, wherein the proportions of two of the components are as follows in % by weight, n d is within the range 1.58 through 1.64, ν d is within the range of 39 through 50 and specific gravity is 2.59 or less: ______________________________________
TiO.sub.2
9.5-20
CaO 0-4.
______________________________________
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-03-13 | 1992-09-12 | 1993-03-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-03-13 | 1996-09-12 | 1997-03-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-03-13 | 2000-09-12 | 2001-03-14 | $7700.00 | Window Closed / Lapsed |