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US2843774A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Light absorbent surfaces
Assignee: EMI Ltd
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Filing: 1953-01-27
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Granted: 1958-07-15
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Expires: 1973-01-27
Abstract
No abstract record available.
Inventors
- 👤 Cassman Harry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 12:48
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/02; H01J29/021; H01J29/86; H01J29/89
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
37 words
AN ELECRON DISHCARGE DEVICE INCLUDING A METAL MEMBER HAVING A BLACK COATING APPLIED TO A SURFACE OF SAID MEMBER AND COMPRISING ALKALI METAL AND A SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF LEAD, TIN, GERMANIUM AND SILICON.
Claim 2
Dependent Claim
37 words
AN ELECRON DISHCARGE DEVICE INCLUDING A METAL MEMBER HAVING A BLACK COATING APPLIED TO A SURFACE OF SAID MEMBER AND COMPRISING ALKALI METAL AND A SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF LEAD, TIN, GERMANIUM AND SILICON.
References Cited (Backward Citations)
US2495042A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-07-14 | 1962-01-13 | 1962-07-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-07-14 | 1966-01-13 | 1966-07-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-07-14 | 1970-01-13 | 1970-07-15 | $7700.00 | Window Closed / Lapsed |