US4251747A
Expired / Lapsed
US
⏱️ 0.0 years remaining
One piece astigmatic grid for color picture tube electron gun
Assignee: Osram Sylvania Inc
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Filing: 1979-11-15
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Granted: 1981-02-17
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Expires: 1999-11-15
Abstract
Abstract A one-piece control grid for functioning as an astigmatic lens in an electron gun has a milled, ground, or machined slot formed across its functional grid area. A suitable beam aperture is provided in the bottom of the slot.
Inventors
- 👤 Glen A. Burdick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 01:43
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/46; H01J29/48; H01J29/488
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
75 words
A one piece, astigmatic grid for a cathode ray tube electron gun comprising: a functional grid area defined by a given perimeter and having a given thickness; a transverse slot formed in said functional grid area having a depth less than that of said given thickness, said slot having a length which extends entirely across said functional grid area; and an aperture within said slot, said aperture penetrating the remaining part of said given thickness.
Claim 2
Dependent Claim
75 words
A one piece, astigmatic grid for a cathode ray tube electron gun comprising: a functional grid area defined by a given perimeter and having a given thickness; a transverse slot formed in said functional grid area having a depth less than that of said given thickness, said slot having a length which extends entirely across said functional grid area; and an aperture within said slot, said aperture penetrating the remaining part of said given thickness.
Claim 3
Dependent Claim
15 words
The grip of claim 1 wherein the walls defined by said slot are substantially parallel.
Claim 4
Dependent Claim
10 words
The grid of claim 2 wherein said aperture is non-circular.
Claim 5
Dependent Claim
10 words
The grid of claim 2 wherein said aperture is circular.
Claim 6
Dependent Claim
21 words
The grid of claim 2 wherein said aperture is substantially square with a radius formed at each of the internal corners.
Claim 7
Dependent Claim
84 words
In a method of making a one piece, astigmatic grid for a cathode ray tube electron gun, the steps comprising: forming a pre-grid with a functional grid area, said functional grid area having a given perimeter and a given thickness; forming a transverse slot in said functional grid, said slot extending entirely across said functional grid area and having a depth less than that of said given thickness; and forming an aperture within said slot, said aperture penetrating the remaining part of said thickness.
Claim 8
Dependent Claim
84 words
In a method of making a one piece, astigmatic grid for a cathode ray tube electron gun, the steps comprising: forming a pre-grid with a functional grid area, said functional grid area having a given perimeter and a given thickness; forming a transverse slot in said functional grid, said slot extending entirely across said functional grid area and having a depth less than that of said given thickness; and forming an aperture within said slot, said aperture penetrating the remaining part of said thickness.
Claim 9
Dependent Claim
12 words
The method of claim 6 wherein said slot is formed by milling.
Claim 10
Dependent Claim
12 words
The method of claim 6 wherein said slot is formed by grinding.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-02-17 | 1984-08-18 | 1985-02-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-02-17 | 1988-08-18 | 1989-02-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-02-17 | 1992-08-18 | 1993-02-17 | $7700.00 | Window Closed / Lapsed |