US3444544A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Light modulated intrusion detection system
Assignee: American District Telegraph Co
•
Filing: 1965-07-19
•
Granted: 1969-05-13
•
Expires: 1985-07-19
Abstract
No abstract record available.
Inventors
- 👤 Howard Pearson
- 👤 Willi A Busch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 17:10
CPC Classifications
G; G08; G08B; G08B19/00; G08B19/005; G08B13/00; G08B13/18; G08B13/181; G08B13/187; G08B13/189; G08B13/19
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1877279A
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US2202060A
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US2282198A
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US2412822A
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US2631273A
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US2813230A
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US2762033A
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US3195043A
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US3156908A
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US3329946A
Cited
US3370284A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-05-12 | 1972-11-11 | 1973-05-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-05-12 | 1976-11-11 | 1977-05-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-05-12 | 1980-11-11 | 1981-05-13 | $7700.00 | Window Closed / Lapsed |