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Patent US4590404A successfully refreshed from Google Patents.
US4590404A
Expired / Lapsed
US
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Cathode-ray tube having a faceplate with decreasing center-to-edge thickness
Assignee: RCA Licensing Corp
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Filing: 1984-03-30
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Granted: 1986-05-20
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Expires: 2004-03-30
Abstract
Abstract An improved cathode-ray tube includes an envelope comprising a faceplate panel, a funnel and a neck. The faceplate panel includes a transparent rectangular faceplate having a cathodoluminescent screen on an interior surface thereof. The faceplate has a vertical minor axis and a horizontal major axis. The improvement comprises the thickness of the faceplate being less near the ends of at least one of the major or minor axes than at its center, whereby the viewing angle in at least one direction is increased. In a preferred embodiment, the thickness of the faceplate increases from center-to-edge along its minor axis and decreases from center-to-edge along its major axis.
Inventors
- 👤 Ralph J. D'Amato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 07:18
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/86; H01J29/861; H01J2229/00; H01J2229/86; H01J2229/8613; H01J2229/8616; H01J2229/862
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
75 words
In a cathode-ray tube including an envelope comprising a faceplate panel, a funnel and a neck, said faceplate panel including a transparent rectangular faceplate having a cathodoluminescent screen on an interior surface thereof, and said faceplate having a minor axis and a major axis, the improvement comprising the thickness of said faceplate increasing from center-to-edge along said minor axis and along cross-sections parallel to said minor axis, and decreasing from center-to-edge along said major axis.
Claim 2
Dependent Claim
75 words
In a cathode-ray tube including an envelope comprising a faceplate panel, a funnel and a neck, said faceplate panel including a transparent rectangular faceplate having a cathodoluminescent screen on an interior surface thereof, and said faceplate having a minor axis and a major axis, the improvement comprising the thickness of said faceplate increasing from center-to-edge along said minor axis and along cross-sections parallel to said minor axis, and decreasing from center-to-edge along said major axis.
Claim 3
Dependent Claim
33 words
The tube as defined in claim 1, wherein the interior surface of said faceplate along said major axis, at the edges of said screen, approximately parallels the adjacent exterior surface of said faceplate.
Claim 4
Dependent Claim
24 words
The tube as defined in claim 1, wherein the thickness of said faceplate also decreases from center-to-edge along cross-sections parallel to said major axis.
References Cited (Backward Citations)
US2728012A
Cited
GB1358161A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-05-19 | 1989-11-18 | 1990-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-05-19 | 1993-11-18 | 1994-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-05-19 | 1997-11-18 | 1998-05-20 | $7700.00 | Window Closed / Lapsed |