Patent US2420252A successfully refreshed from Google Patents.
US2420252A
Expired / Lapsed
US
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Optical interference sight for guns, cameras, or the like
Assignee: Polaroid Corp
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Filing: 1945-03-23
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Granted: 1947-05-06
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Expires: 1965-03-23
Abstract
No abstract record available.
Inventors
- 👤 Edwin H Land
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:57
CPC Classifications
F; F41; F41G; F41G1/00; F41G1/02; F41G1/027; G; G02; G02B; G02B27/00; G02B27/32
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2160202A
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US942393A
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GB191515708A
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US1610532A
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US1926716A
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GB378742A
Cited
US2018214A
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US2099694A
Cited
US2105671A
Cited
US2313204A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-05-05 | 1950-11-04 | 1951-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-05-05 | 1954-11-04 | 1955-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-05-05 | 1958-11-04 | 1959-05-06 | $7700.00 | Window Closed / Lapsed |