US3686028A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Masked photocathode
Assignee: Westinghouse Electric Corp
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Filing: 1970-09-24
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Granted: 1972-08-22
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Expires: 1990-09-24
Abstract
Abstract A SHADOW MASK PARTICULARLY FOR USE WITH ULTRAVIOLET SENSITIVE PHOTOCATHODES IS PROVIDED OF A MATERIAL THAT DOES NOT TRANSMIT ULTRAVIOLET RADIATION AND WHICH, FURTHERMORE, DOES NOT ABSORBS OTHER WAVELENGTH RADIATION, SUCH AS VISIBLE. THIS PERMITS THE PHOTOCATHODE TO BE IMMEDIATELY ADJACENT THE MASK BECAUSE WHEN EXPOSED BY A HIGHLY INTENSITY LIGHT SOURCE APPRECIABLE HEATING IN THE MASK MATERIAL THAT WOULD DAMAGE THE PHOTOCATHODE DOES NOT OCCUR. THE MASK MAY BE, FOR EXAMPLE, AN ULTRAVILET ABSORBER, SUCH AS TITANIUM IONS IN A TITANIUM OXIDE.
Inventors
- 👤 Terence W O'keeffe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 13:44
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/02; H01J29/10; H01J29/36; H01J29/38
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) | 1975-08-22 | 1976-02-21 | 1976-08-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-22 | 1980-02-21 | 1980-08-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-22 | 1984-02-21 | 1984-08-22 | $7700.00 | Window Closed / Lapsed |