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US3540795A
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Achromatic compensation apparatus using polarization rotation and birefringent elements
Assignee: International Business Machines Corp
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Filing: 1969-01-15
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Granted: 1970-11-17
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Expires: 1989-01-15
Abstract
No abstract record available.
Inventors
- 👤 Thomas J Harris
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:56
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/0025
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3183763A
Cited
US3497284A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-11-16 | 1974-05-18 | 1974-11-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-11-16 | 1978-05-18 | 1978-11-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-11-16 | 1982-05-18 | 1982-11-17 | $7700.00 | Window Closed / Lapsed |