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US3268331A
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Persistent internal polarization systems
Assignee: Northrop Grumman Guidance and Electronics Co Inc
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Filing: 1962-05-24
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Granted: 1966-08-23
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Expires: 1982-05-24
Abstract
No abstract record available.
Inventors
- 👤 Richard K Harper
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 17:51
CPC Classifications
G; G03; G03G; G03G5/00; G03G5/02; G03G5/024; G03G13/00; G03G13/056; H; H01; H01G; H01G7/00; H01G7/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2922883A
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US2955938A
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US3005707A
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US2976447A
Cited
US3199086A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-08-22 | 1970-02-21 | 1970-08-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-08-22 | 1974-02-21 | 1974-08-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-08-22 | 1978-02-21 | 1978-08-23 | $7700.00 | Window Closed / Lapsed |