US2597589A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrooptical device
Assignee: AT&T Inc
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Filing: 1949-04-08
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Granted: 1952-05-20
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Expires: 1969-04-08
Abstract
No abstract record available.
Inventors
- 👤 Bernd T Matthias
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 04:21
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/495; G; G02; G02F; G02F1/00; G02F1/0009; G02F1/0018; Y; Y10; Y10T; Y10T29/00; Y10T29/42
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
49 words
AN ELETRO-OPTICAL DEVICE COMPRISING A PAIR OF SPACED POLARIZING FILTERS AND DISPOSED THEREBETWEEN A CRYSTAL CONSISTING ESSENTIALLY OF AT LEAST ONE SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF SODIUM METACOLUMBATE, POTASSIUM METACOLUMBATE, SODIUM METATANTALATE AND POTASSIUM METATANTALATE, SAID CRYSTAL HAVING A PAIR OF ELECTRODES DISPOSED ON OPPOSITE SURFACES THEREOF.
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) | 1955-05-20 | 1955-11-19 | 1956-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-05-20 | 1959-11-19 | 1960-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-05-20 | 1963-11-19 | 1964-05-20 | $7700.00 | Window Closed / Lapsed |