Patent US2866712A successfully refreshed from Google Patents.
US2866712A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical crown glass
Assignee: Individual
•
Filing: 1953-11-16
•
Granted: 1958-12-30
•
Expires: 1973-11-16
Abstract
No abstract record available.
Inventors
- 👤 Weissenberg Gustav
- 👤 Ungemach Otto
- 👤 Meinert Norbert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 20:53
CPC Classifications
C; C03; C03C; C03C3/00; C03C3/12; C03C3/14; C03C3/15; C03C3/155; C03C3/142; C03C3/145; Y; Y10; Y10S; Y10S501/00; Y10S501/90; Y10S501/903
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
82 words
OPTICAL CROWN GLASS WITH ANOMALOUS PARTIAL DISPERSION CONSISTING ESSENTIALLY OF FROM ABOUT 47% TO 75% BY WEIGHT OF BORIC ACID ANHYDRIDE, FROM ABOUT 4% TO 17% BY WEIGHT OF ZIRCONIUM OXIDE AND FROM ABOUT 15% TO 41% BY WEIGHT OF AN ALKALI CARBONATE AND OF A MIXTURE OF LANTHANUM OXIDE AND ALKALINE EARTH OXIDE IN AMOUNT FROM ABOUT 35% BY WEIGHT TO ABOUT 52.5% BY WEIGHT IN WHICH MIXTURE THE ALKALINE EARTH OXIDE DOES NOT EXCEED 10% BY WEIGHT OF THE GLASS.
Claim 2
Dependent Claim
82 words
OPTICAL CROWN GLASS WITH ANOMALOUS PARTIAL DISPERSION CONSISTING ESSENTIALLY OF FROM ABOUT 47% TO 75% BY WEIGHT OF BORIC ACID ANHYDRIDE, FROM ABOUT 4% TO 17% BY WEIGHT OF ZIRCONIUM OXIDE AND FROM ABOUT 15% TO 41% BY WEIGHT OF AN ALKALI CARBONATE AND OF A MIXTURE OF LANTHANUM OXIDE AND ALKALINE EARTH OXIDE IN AMOUNT FROM ABOUT 35% BY WEIGHT TO ABOUT 52.5% BY WEIGHT IN WHICH MIXTURE THE ALKALINE EARTH OXIDE DOES NOT EXCEED 10% BY WEIGHT OF THE GLASS.
References Cited (Backward Citations)
US2678281A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-12-29 | 1962-06-30 | 1962-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-12-29 | 1966-06-30 | 1966-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-12-29 | 1970-06-30 | 1970-12-30 | $7700.00 | Window Closed / Lapsed |