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US3408430A
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Method for improving the visible and infrared transmission of hot pressed magnesium fluoride
Assignee: Corning Glass Works
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Filing: 1965-03-17
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Granted: 1968-10-29
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Expires: 1985-03-17
Abstract
No abstract record available.
Inventors
- 👤 Irwin M Lachman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 07:08
CPC Classifications
C; C01; C01F; C01F5/00; C01F5/26; C01F5/28; C04; C04B; C04B33/00; C04B33/02; C04B33/04; C04B33/06; C04B33/30
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) | 1971-10-29 | 1972-04-29 | 1972-10-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-10-29 | 1976-04-29 | 1976-10-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-10-29 | 1980-04-29 | 1980-10-29 | $7700.00 | Window Closed / Lapsed |