Patent US3898093A successfully refreshed from Google Patents.
US3898093A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Highly refracting optical glass for correction of high diopter values with low density
Assignee: Schott AG
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Filing: 1973-11-30
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Granted: 1975-08-05
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Expires: 1993-11-30
Abstract
Abstract An optical quality glass suitable for use in eyeglass lenses, characterized by having a refractive index nd of at least 1.70; a specific gravity of not more than 3.0 and a thermal coefficient of expansion Alpha X 107 per *C of not more than 100, which contains at least 90 mol % of metal oxide components having a molecular weight of not more than 100, and which consists essentially of at least 90 mol % of SiO2, B2O3, Li2O, Na2O, K2O, MgO, CaO, ZnO, TiO2 and a crystallization stabilizing amount of up to about 10 mol % of at least one member selected from the group consisting of SrO, BaO, ZrO2, Ta2O5 and Nb2O5.
Inventors
- 👤 Marga Faulstich
- 👤 Volkmar Geiler
- 👤 Georg Gliemeroth
- 👤 Lothar Meckel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:22
CPC Classifications
C; C03; C03C; C03C3/00; C03C3/04; C03C3/076; C03C3/089; C03C3/091; C03C3/093; Y; Y10; Y10S; Y10S501/00; Y10S501/90; Y10S501/903
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
172 words
AN OPTICAL QUALITY GLASS SUITABLE FOR USE IN EYEGLASS LENSES, CHARACTERIZED BY HAVING A REFRACTIVE INDEX ND OF AT LEAST 1.70, A SPECIFIC GRAVITY OF NOT MORE THAN 3.0 AND A THERMAL COEFFICIENT OF EXPANSION AX10**7 PER *C OF NOT MORE THAN 100, WHICH CONTAINS AT LEAST 90 MOL % OF METAL OXIDE COMPONENTS HAVING A MOLECULAR WEIGHT OF NOT MORE THAN 100, AND WHICH CONSISTS ESSENTIALLY OF AT LEAST 90 MOL % OF SIO2, B2O3, LI2O, NA2O, K2O, TIO2, MGO, CAO, ZNO AND CRYSTALLIZATION STABILIZING AMOUNT OF UP TO ABOUT 10 MOL% OF AT LEAST ONE MEMBER SELECTED FROM THE GROUP CONSISTING OF SRO, BAO, ZRO2, TA2O5 AND NB2O5, SAID GLASS BEING FURTHER CHARACTERIZED BY CONSISTING ESSENTIALLY OF, IN PARTS BY WEIGHT PER 100 PARTS OF GLASS, A. 40-45 WT % SIO2 AND 2-6 WT % B2O3, THE TOTAL SIO2 AND B2O3 BEING 42-49 WT %, B. 12-17 WT % TOTAL LI2O, NA2O AND K2O, INCLUDING 6-16 WT % NA2O, C. 24-26 WT % TIO2, AND D. 2-7 WT % ZRO2.
Claim 2
Dependent Claim
172 words
AN OPTICAL QUALITY GLASS SUITABLE FOR USE IN EYEGLASS LENSES, CHARACTERIZED BY HAVING A REFRACTIVE INDEX ND OF AT LEAST 1.70, A SPECIFIC GRAVITY OF NOT MORE THAN 3.0 AND A THERMAL COEFFICIENT OF EXPANSION AX10**7 PER *C OF NOT MORE THAN 100, WHICH CONTAINS AT LEAST 90 MOL % OF METAL OXIDE COMPONENTS HAVING A MOLECULAR WEIGHT OF NOT MORE THAN 100, AND WHICH CONSISTS ESSENTIALLY OF AT LEAST 90 MOL % OF SIO2, B2O3, LI2O, NA2O, K2O, TIO2, MGO, CAO, ZNO AND CRYSTALLIZATION STABILIZING AMOUNT OF UP TO ABOUT 10 MOL% OF AT LEAST ONE MEMBER SELECTED FROM THE GROUP CONSISTING OF SRO, BAO, ZRO2, TA2O5 AND NB2O5, SAID GLASS BEING FURTHER CHARACTERIZED BY CONSISTING ESSENTIALLY OF, IN PARTS BY WEIGHT PER 100 PARTS OF GLASS, A. 40-45 WT % SIO2 AND 2-6 WT % B2O3, THE TOTAL SIO2 AND B2O3 BEING 42-49 WT %, B. 12-17 WT % TOTAL LI2O, NA2O AND K2O, INCLUDING 6-16 WT % NA2O, C. 24-26 WT % TIO2, AND D. 2-7 WT % ZRO2.
Claim 3
Dependent Claim
18 words
An optical glass according to claim 1, consisting essentially of, in % by weight of the total composition:
Claim 4
Dependent Claim
10 words
An optical glass according to claim 2, having properties of
Claim 5
Dependent Claim
11 words
An optical glass according to claim 2, having the properties of
Claim 6
Dependent Claim
11 words
An optical glass according to claim 2, having the properties of
Claim 7
Dependent Claim
13 words
The glass composition of claim 1 in the form of an eyeglass lens.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-08-04 | 1979-02-03 | 1979-08-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-04 | 1983-02-03 | 1983-08-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-04 | 1987-02-03 | 1987-08-05 | $7700.00 | Window Closed / Lapsed |