Patent US3683224A successfully refreshed from Google Patents.
US3683224A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low depth cathode ray tubes
Assignee: Rank Brimar Ltd
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Filing: 1969-05-05
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Granted: 1972-08-08
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Expires: 1989-05-05
Abstract
Abstract A cathode ray tube has an evacuated shallow envelope provided with a flat screen, and an electron gun is arranged to direct an electron beam into the envelope from one edge thereof in a direction which is substantially parallel to the plane of the screen. The beam is deflected by controlled deflection electrodes towards the screen to control the distance from said edge at which the beam impinges on the screen. An electrode arrangement is provided in the envelope for deflecting the beam towards the screen by an amount which increases with increasing distance from said edge of the envelope In this way the angle of attack of the beam on the screen at all positions along the screen is greater than it would be in the absence of the electrode arrangement. A grid may be arranged in the envelope parallel to an immediately behind the screen, the grid being connected to a D.C. source such that the angle of attach of the electron beam relative to the screen is further increased as the beam passes through the grid.
Inventors
- 👤 Peter Gordon Lea
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:31
CPC Classifications
H; H01; H01J; H01J31/00; H01J31/08; H01J31/10; H01J31/12; H01J31/123; H01J31/124
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
152 words
A cathode ray tube comprising: an evacuated shallow envelope, a substantially flat screen having thereon a phosphor layer disposed within the envelope, an electron gun which directs an electron beam into the envelope from one edge thereof in a direction which is substantially parallel to the plane of the screen, beam deflection means within the envelope for selectively deflecting the electron beam towards the screen, an electrode arrangement in the envelope comprising an array of elongated electrodes, electrically separate from the said deflection means, said electrodes extending parallel to said screen across a width thereof and being spaced apart, in a direction parallel to the screen, by respective distances which increase progressively towards the beam deflection means, and a source of steady potential connected to said electrode arrangement to deflect the electron beam further towards said screen, the amount of said further deflection increasing with increasing distance from said beam deflection means.
Claim 2
Dependent Claim
152 words
A cathode ray tube comprising: an evacuated shallow envelope, a substantially flat screen having thereon a phosphor layer disposed within the envelope, an electron gun which directs an electron beam into the envelope from one edge thereof in a direction which is substantially parallel to the plane of the screen, beam deflection means within the envelope for selectively deflecting the electron beam towards the screen, an electrode arrangement in the envelope comprising an array of elongated electrodes, electrically separate from the said deflection means, said electrodes extending parallel to said screen across a width thereof and being spaced apart, in a direction parallel to the screen, by respective distances which increase progressively towards the beam deflection means, and a source of steady potential connected to said electrode arrangement to deflect the electron beam further towards said screen, the amount of said further deflection increasing with increasing distance from said beam deflection means.
Claim 3
Dependent Claim
29 words
Cathode ray tube as claimed in claim 1, wherein the electrodes are constituted by conductive strips deposited on an insulating substrate which is suitable for use within said envelope.
Claim 4
Dependent Claim
32 words
Cathode ray tube as claimed in claim 1, wherein the said beam deflection means comprise a pair of spaced apart deflection plates extending parallel to the screen and across a width thereof.
Claim 5
Dependent Claim
54 words
Cathode ray tube as claimed in claim 1, including a grid disposed in the envelope parallel to and immediately behind the screen, and a source of potential connectible to said grid to cause the angle of impingement of the electron beam on the screen to be increased as the beam passes through the grid.
Claim 6
Dependent Claim
28 words
Cathode ray tube as claimed in claim 4, wherein the screen incorporates an electrically conductive layer, said source of potential providing a potential above that of the grid.
Claim 7
Dependent Claim
32 words
Cathode ray tube as claimed in claim 1, including line scanning means for deflecting the electron beam in a line direction perpendicular to the beam deflection effected by the said deflection means.
Claim 8
Dependent Claim
45 words
Cathode ray tube as claimed in claim 1, wherein the envelope has a neck communicating with the envelope at said one edge of the screen, and the electron gun is disposed in said neck, the beam deflection means being located at or adjacent said edge.
Claim 9
Dependent Claim
67 words
Cathode way tube as claimed in claim 1, including electron beam line scanning and collimating means in the envelope and a reversing electrode arranged in the envelope at the opposite edge thereof to reverse the direction of the electron beam to direct the latter parallel to the screen from the opposite edge of the envelope, the beam deflection means being located at or adjacent said opposite edge.
Claim 10
Dependent Claim
39 words
Cathode ray tube as claimed in claim 1, wherein said screen comprises a transparent substantially flat window forming at least part of one face of the envelope, the phosphor layer being deposited on the internal surface of said window.
Claim 11
Dependent Claim
43 words
Cathode ray tube as claimed in claim 1, wherein the envelope has a transparent face and the screen comprises a substantially flat substrate disposed parallel to and spaced from the transparent face of the envelope, the phosphor layer being deposited on said substrate.
References Cited (Backward Citations)
US2100703A
Cited
US2728025A
Cited
US2961575A
Cited
US2880365A
Cited
US2878417A
Cited
US2842711A
Cited
US3435277A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-08 | 1976-02-07 | 1976-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-08 | 1980-02-07 | 1980-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-08 | 1984-02-07 | 1984-08-08 | $7700.00 | Window Closed / Lapsed |