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US2456708A
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Apparatus for improving the durability of optical coatings
Assignee: RCA Corp
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Filing: 1944-05-01
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Granted: 1948-12-21
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Expires: 1964-05-01
Abstract
No abstract record available.
Inventors
- 👤 Edward W Kellogg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:59
CPC Classifications
C; C23; C23C; C23C14/00; C23C14/58; C23C14/5806; C23C14/582
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1965582A
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US1965587A
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US2239642A
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US2178233A
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US2164595A
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GB510404A
Cited
US2281638A
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US2301456A
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US2391595A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-12-21 | 1952-06-21 | 1952-12-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-12-21 | 1956-06-21 | 1956-12-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-12-21 | 1960-06-21 | 1960-12-21 | $7700.00 | Window Closed / Lapsed |