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US4415464A
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Faraday rotation glass
Assignee: Hoya Corp
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Filing: 1982-03-12
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Granted: 1983-11-15
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Expires: 2002-03-12
Abstract
Abstract A Faraday rotation glass comprising, in mole %, ______________________________________ P 2 O 5 5 to 30% where up to 5/6 on a molar basis of the P 2 O 5 can be replaced by B 2 O 3 ; TbF 3 11.4 to 45%; AlF 3 0 to 25%; and RF at least 40% ______________________________________ where RF includes at least 3% BaF 2 , 0 to 64% MgF 2 , 0 to 32% NaF, 0 to 40% SrF 2 , 0 to 26% CaF 2 , 0 to 20% LiF and 0 to 20% KF.
Inventors
- 👤 Yoshiyuki Asahara
- 👤 Tetsuro Izumitani
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 18:46
CPC Classifications
C; C03; C03C; C03C4/00; C03C3/00; C03C3/12; C03C3/23; C03C3/247
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
89 words
A Faraday rotation glass consisting essentially of in mole %, ______________________________________
P.sub.2 O.sub.5
5 to 30% where up to 5/6 on
a molar basis of the P.sub.2 O.sub.5 can be
replaced by B.sub.2 O.sub.3 ;
TbF.sub.3 11.4 to 45%;
AlF.sub.3 0 to 25%; and
RF at least 40%
______________________________________ where RF includes at least 3% BaF 2 , 0 to 64% MgF 2 , 0 to 32% NaF, 0 to 40% SrF 2 , 0 to 26% CaF 2 , 0 to 20% LiF and 0 to 20% KF.
Claim 2
Dependent Claim
89 words
A Faraday rotation glass consisting essentially of in mole %, ______________________________________
P.sub.2 O.sub.5
5 to 30% where up to 5/6 on
a molar basis of the P.sub.2 O.sub.5 can be
replaced by B.sub.2 O.sub.3 ;
TbF.sub.3 11.4 to 45%;
AlF.sub.3 0 to 25%; and
RF at least 40%
______________________________________ where RF includes at least 3% BaF 2 , 0 to 64% MgF 2 , 0 to 32% NaF, 0 to 40% SrF 2 , 0 to 26% CaF 2 , 0 to 20% LiF and 0 to 20% KF.
Claim 3
Dependent Claim
21 words
The glass of claim 1 containing up to 10 mole % NaF or up to 17 mole % BaF 2 .
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) | 1986-11-14 | 1987-05-16 | 1987-11-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-11-14 | 1991-05-16 | 1991-11-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-11-14 | 1995-05-16 | 1995-11-15 | $7700.00 | Window Closed / Lapsed |