Patent US3761756A successfully refreshed from Google Patents.
US3761756A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluorescent screens for use in cathode ray tubes
Assignee: Hitachi Ltd
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Filing: 1971-12-28
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Granted: 1973-09-25
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Expires: 1991-12-28
Abstract
Abstract In a fluorescent screen for use in a cathode ray tube used for image formation of the class including a phosphor film coated on the surface of a face plate, there are provided a plurality of hills and valleys on one surface of the face plate, and a phosphor film coated on the tops of the hills. The side walls of the valleys are inclined such that they reflect the light emanated from the phosphor film toward the other surface of the face plate.
Inventors
- 👤 K Miura
- 👤 Y Tomita
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 12:58
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/02; H01J29/10; H01J29/18; H01J29/28; H01J29/187; H01J29/24
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
30 words
The fluorescent screen according to claim 1 wherein said side walls of said valleys are inclined from 10* to 40* with respect to the normal perpendicular to said phosphor film.
Claim 2
Dependent Claim
23 words
The fluorescent screen according to claim 1 wherein at least the reflective side walls of said valleys are coated with a reflective film.
Claim 3
Dependent Claim
21 words
The fluorescent screen according to claim 1 wherein said valleys have a depth of from several microns to several hundred microns.
Claim 4
Dependent Claim
24 words
The fluorescent screen according to claim 3 wherein said reflective film is an aluminum film having a thickness of about 1,000 to 6,000 A.
Claim 5
Dependent Claim
28 words
The fluorescent screen according to claim 3 wherein said reflectivE film is a film of a powder of aluminum oxide having a grain size of about 10 microns.
Claim 6
Dependent Claim
110 words
A fluorescent screen for use in shadow mask type color picture tubes comprising a light transmissive face plate, a plurality of hills and valleys interconnected by sloping side wall surfaces formed on the inner surface of said face plate, phosphor dots of three original colours applied on the tops of said hills, said side wall surfaces of said valleys being inclined so as to internally reflect the portion of light emanated from said phosphor film and intercepted by said side wall surfaces toward the other surface of said face plate, and a reflective film of metal covering said phosphor film on said dots and the inner surfaces of said valleys.
Claim 7
Dependent Claim
100 words
A fluorescent screen for use in Chromatron type color picture tubes comprising a face plate, raised stripes and valleys interconnected by side walls formed on the inner surface of said face plate, a phosphor film of three original colours coated on the tops of said raised stripes, said side walls of said valleys being inclined so as to internally reflect the portion of light emanated from said phosphor film and intercepted by said side walls toward the other surface of said face plate, and a reflective film of metal covering said phosphor film and the inner surfaces of said valleys.
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) | 1976-09-24 | 1977-03-26 | 1977-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-24 | 1981-03-26 | 1981-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-24 | 1985-03-26 | 1985-09-25 | $7700.00 | Window Closed / Lapsed |