US3495891A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Floating mark systems in a stereoscopic device
Assignee: Northrop Grumman Guidance and Electronics Co Inc
•
Filing: 1967-12-18
•
Granted: 1970-02-17
•
Expires: 1987-12-18
Abstract
No abstract record available.
Inventors
- 👤 Roger K Lee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 09:50
CPC Classifications
G; G02; G02B; G02B30/00; G02B30/20; G02B30/34; G02B30/35; G01; G01C; G01C11/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1514948A
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US1864899A
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US1987765A
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US2230993A
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US2404302A
Cited
US2388858A
Cited
US2674152A
Cited
US3194108A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-02-16 | 1973-08-18 | 1974-02-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-02-16 | 1977-08-18 | 1978-02-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-02-16 | 1981-08-18 | 1982-02-17 | $7700.00 | Window Closed / Lapsed |