Patent US3655978A successfully refreshed from Google Patents.
US3655978A
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Zinc cadmium sulfide cathodoluminescent screen
Assignee: GTE Sylvania Inc
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Filing: 1970-09-04
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Granted: 1972-04-11
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Expires: 1990-09-04
Abstract
Abstract An improved viewing screen for use in electron microscopes can be obtained when a phosphor consisting essentially of zinc sulfide and cadmium sulfide, in specific ratios, and a source of an activator material containing specified amounts of an aluminum source and specified amounts of either copper or silver is substrated on a rigid electrically conductive support.
Inventors
- 👤 Sixdeniel Faria
- 👤 David J Harrigan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 02:01
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/02; H01J37/22; H01J37/224; C; C09; C09K; C09K11/00; C09K11/08; C09K11/64; C09K11/641; C09K11/642
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
19 words
A screen according to claim 1, wherein said cathodoluminescent phosphor is suspended in a transparent solution castable film material.
Claim 2
Dependent Claim
12 words
A screen according to claim 2, wherein said rigid support is metallic.
Claim 3
Dependent Claim
12 words
A screen according to claim 2, wherein said rigid support is non-metallic.
Claim 4
Dependent Claim
23 words
A screen according to claim 1, wherein said phosphor has a zinc to cadmium weight ratio of from about 90:10 to about 97:3.
Claim 5
Dependent Claim
11 words
A screen according to claim 5, wherein said activator is silver.
Claim 6
Dependent Claim
11 words
A screen according to claim 5, wherein said activator is copper.
Claim 7
Dependent Claim
23 words
A screen according to claim 1, wherein said phosphor has a zinc to cadmium weight ratio of from about 55:45 to about 65:35.
Claim 8
Dependent Claim
11 words
A screen according to claim 8, wherein said activator is silver.
References Cited (Backward Citations)
US2623858A
Cited
US3197636A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-04-11 | 1975-10-11 | 1976-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-11 | 1979-10-11 | 1980-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-11 | 1983-10-11 | 1984-04-11 | $7700.00 | Window Closed / Lapsed |