Patent US3892995A successfully refreshed from Google Patents.
US3892995A
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Post-deflection acceleration type color picture tube
Assignee: Hitachi Ltd
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Filing: 1970-09-16
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Granted: 1975-07-01
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Expires: 1990-09-16
Abstract
Abstract A post-deflection acceleration type color picture tube wherein the diameter of dot-like phosphors formed on a phosphor screen on the inner surface of a face plate of a glass bulb is made smaller than the diameter of electron beams when impinging upon the phosphors, and therewith, wherein a non-luminescent black substance is deposited into gaps between the respective adjacent dot-like phosphors so as to fill up the gaps to provide the phosphor screen, whereby the brightness, contrast and color purity of a picture screen are enhanced and any deterioration in a picture due to halation is reduced.
Inventors
- 👤 Eiichi Yamazaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 11:28
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/02; H01J29/10; H01J29/18; H01J29/30; H01J29/32
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
123 words
In a post-deflection acceleration type color picture tube including a glass bulb having a panel portion, a funnel portion and a neck portion, a phosphor screen disposed on the inner surface of a face plate of said panel portion, and a color selective electrode disposed just in front of said phosphor screen inside said glass bulb, the improvement comprising said phosphor screen being provided with phosphor dots which are smaller in diameter than the diameter of the focussed electron beams reaching said phosphor screen, wherein gaps between the adjacent phosphor dots on said phosphor screen are filled up with a non-luminescent black substance, and wherein the postdeflection accelerating voltage ratio between said phosphor screen and said color selective electrode is 1.5 - 3.0.
Claim 2
Dependent Claim
123 words
In a post-deflection acceleration type color picture tube including a glass bulb having a panel portion, a funnel portion and a neck portion, a phosphor screen disposed on the inner surface of a face plate of said panel portion, and a color selective electrode disposed just in front of said phosphor screen inside said glass bulb, the improvement comprising said phosphor screen being provided with phosphor dots which are smaller in diameter than the diameter of the focussed electron beams reaching said phosphor screen, wherein gaps between the adjacent phosphor dots on said phosphor screen are filled up with a non-luminescent black substance, and wherein the postdeflection accelerating voltage ratio between said phosphor screen and said color selective electrode is 1.5 - 3.0.
Claim 3
Dependent Claim
127 words
In a post-deflection acceleration type color cathode ray tube including a phosphor screen disposed on the surface of a face plate and provided with a plurality of color phosphor elements, and a color selective electrode disposed in front of thE phosphor screen, the phosphor screen being supplied with an electric potential higher than that of the color selective electrode so as to focus electron beams passing through the color selective electrode, the improvement comprising the phosphor screen being formed of spaced phosphor elements which are smaller in size than the focussed electron beams reaching the phosphor screen, a non-luminescent black substance filling the gaps between adjacent phosphor elements, and the post-deflection accelerating voltage ratio of the phosphor screen and the color selective electrode being 1.5 to 3.0.
Claim 4
Dependent Claim
127 words
In a post-deflection acceleration type color cathode ray tube including a phosphor screen disposed on the surface of a face plate and provided with a plurality of color phosphor elements, and a color selective electrode disposed in front of thE phosphor screen, the phosphor screen being supplied with an electric potential higher than that of the color selective electrode so as to focus electron beams passing through the color selective electrode, the improvement comprising the phosphor screen being formed of spaced phosphor elements which are smaller in size than the focussed electron beams reaching the phosphor screen, a non-luminescent black substance filling the gaps between adjacent phosphor elements, and the post-deflection accelerating voltage ratio of the phosphor screen and the color selective electrode being 1.5 to 3.0.
References Cited (Backward Citations)
US3548249A
Cited
US3614504A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-30 | 1978-12-30 | 1979-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-30 | 1982-12-30 | 1983-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-30 | 1986-12-30 | 1987-07-01 | $7700.00 | Window Closed / Lapsed |