Patent US3442572A successfully refreshed from Google Patents.
US3442572A
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Assignee: Optical Coating Laboratory Inc
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Filing: 1964-08-25
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Granted: 1969-05-06
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Expires: 1984-08-25
Abstract
No abstract record available.
Inventors
- 👤 Rolf F Illsley
- 👤 Alfred J Thelen
- 👤 Joseph H Apfel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:28
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/20; G02B5/28; G02B5/285; C; C23; C23C; C23C14/00; C23C14/04; C23C14/042; C23C14/044; G01; G01J; G01J3/00; G01J3/12; G02B26/00; G02B26/007
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-05-05 | 1972-11-04 | 1973-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-05-05 | 1976-11-04 | 1977-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-05-05 | 1980-11-04 | 1981-05-06 | $7700.00 | Window Closed / Lapsed |