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US4084978A
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US
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Glass for eye glass lens
Assignee: Hoya Corp
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Filing: 1976-12-10
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Granted: 1978-04-18
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Expires: 1996-12-10
Abstract
Abstract A glass for an eye glass lens having a composition comprising, in weight percent, 36 to 50% SiO 2 + Al 2 O 3 + B 2 O 3 , but with 20 to 50% SiO 2 , 0 to 13% Al 2 O 3 and 0 to 20% B 2 O 3 ; 5 to 35% CaO + MgO, but with 5 to 35% CaO and 0 to 20% MgO; 1 to 20% Li 2 O + Na 2 O + K 2 O, but with 0 to 15% Li 2 O and 0 to 15% Na 2 O + K 2 O; 16 to 34% ZrO 2 + TiO 2 + Nb 2 O 5 , but with 0 to 11% ZrO 2 , 0 to 3% TiO 2 and 8 to 30% Nb 2 O 5 ; 0 to 15% BaO + SrO + ZnO; and 0 to 15% La 2 O 3 + Ta 2 O 5 + WO 3 ; with the glass having further a refractive index and ≧1.69, an Abbe number νd≧40, and a specific gravity ≦3.2.
Inventors
- 👤 Hiroji Sagara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:41
CPC Classifications
C; C03; C03C; C03C3/00; C03C3/04; C03C3/076; C03C3/078; C03C3/062; C03C3/064; C03C3/089; C03C3/091; Y; Y10; Y10S; Y10S501/00; Y10S501/90; Y10S501/903
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
164 words
A glass for an eye glass lens comprising, in weight percent, 36 to 50% SiO 2 + Al 2 O 3 + B 2 O 3 , but with 20 to 50% SiO 2 , 0 to 13% Al 2 O 3 , and 0 to 20% B 2 O 3 ; 5 to 35% CaO + MgO, but with 5 to 35% CaO and 0 to 20% MgO; 1 to 20% Li 2 O + Na 2 O + K 2 O, but with 0 to 15% Li 2 O and 0 to 15% Na 2 O + K 2 O; 16 to 34% ZrO 2 + TiO 2 + Nb 2 O 5 , but with 0 to 11% ZrO 2 , 0 to 3% TiO 2 , and 8 to 30% Nb 2 O 5 ; 0 to 15% BaO + SrO + ZnO; and 0 to 15% La 2 O 3 + Ta 2 O 5 + WO 3 .
Claim 2
Dependent Claim
164 words
A glass for an eye glass lens comprising, in weight percent, 36 to 50% SiO 2 + Al 2 O 3 + B 2 O 3 , but with 20 to 50% SiO 2 , 0 to 13% Al 2 O 3 , and 0 to 20% B 2 O 3 ; 5 to 35% CaO + MgO, but with 5 to 35% CaO and 0 to 20% MgO; 1 to 20% Li 2 O + Na 2 O + K 2 O, but with 0 to 15% Li 2 O and 0 to 15% Na 2 O + K 2 O; 16 to 34% ZrO 2 + TiO 2 + Nb 2 O 5 , but with 0 to 11% ZrO 2 , 0 to 3% TiO 2 , and 8 to 30% Nb 2 O 5 ; 0 to 15% BaO + SrO + ZnO; and 0 to 15% La 2 O 3 + Ta 2 O 5 + WO 3 .
Claim 3
Dependent Claim
38 words
The glass for an eye glass lens as claimed in claim 1 wherein said glass has a refractive index of 1.69 or higher, an Abbe number of 40 or higher, and a specific gravity of 3.2 or lower.
References Cited (Backward Citations)
US3877953A
Cited
US3898093A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-04-17 | 1981-10-17 | 1982-04-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-04-17 | 1985-10-17 | 1986-04-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-04-17 | 1989-10-17 | 1990-04-18 | $7700.00 | Window Closed / Lapsed |