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US2270535A
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Light polarizer and optical system employing the same
Assignee: Polaroid Corp
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Filing: 1938-06-29
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Granted: 1942-01-20
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Expires: 1958-06-29
Abstract
No abstract record available.
Inventors
- 👤 Edwin H Land
- 👤 Clinton J T Young
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:30
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/28; G02B27/283; F; F21; F21S; F21S41/00; F21S41/10; F21S41/12; F21S41/135; G02B5/00; G02B5/30; G02B5/3025
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1945-01-19 | 1945-07-21 | 1946-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1949-01-19 | 1949-07-21 | 1950-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1953-01-19 | 1953-07-21 | 1954-01-20 | $7700.00 | Window Closed / Lapsed |