US3743492A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Amorphous,non-devitrious fluorophosphate optical glass,free of yellow coloring and process for producing the same
Assignee: Hoya Glass Works Ltd
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Filing: 1971-08-31
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Granted: 1973-07-03
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Expires: 1991-08-31
Abstract
Abstract RAW MATERIALS FOR A FLUOROPHOSPHATE OPTICAL GLASS ARE MELTED IN A NON-OXIDIZING ATMOSPHERE, AND IN PARTICULAR, IN A NITROGEN GAS ATOOSPHERE OR IN A COVERED MELTING VESSEL.
Inventors
- 👤 N Ogita
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 02:27
CPC Classifications
C; C03; C03C; C03C3/00; C03C3/12; C03C3/23; C03C3/247; C03B; C03B5/00; C03B5/06; C03B5/08; C03B5/16; C03B5/18; C03B5/187; C03B5/1875; C03B2201/00; C03B2201/60; C03B2201/70; Y; Y10; Y10S; Y10S501/00; Y10S501/90
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) | 1976-07-02 | 1977-01-01 | 1977-07-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-02 | 1981-01-01 | 1981-07-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-02 | 1985-01-01 | 1985-07-03 | $7700.00 | Window Closed / Lapsed |