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US2430218A
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Electron tube with secondary emissive grid
Assignee: Varian Medical Systems Inc
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Filing: 1944-03-21
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Granted: 1947-11-04
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Expires: 1964-03-21
Abstract
No abstract record available.
Inventors
- 👤 William W Eitel
- 👤 Jack A Mccullough
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 18:26
CPC Classifications
H; H01; H01J; H01J19/00; H01J19/42; H01J2893/00; H01J2893/0001; H01J2893/0002
Claims Analysis
Total Claims: 0
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-11-03 | 1951-05-05 | 1951-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-11-03 | 1955-05-05 | 1955-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-11-03 | 1959-05-05 | 1959-11-04 | $7700.00 | Window Closed / Lapsed |