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US 4,251,747 AGranted
One piece astigmatic grid for color picture tube electron gun
AssigneeGTE Products Corporation
InventorGlen A. Burdick
Life of this patent
Estimating the term…
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.
Claims8
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.
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.
Dependencies are inferred from the claim text.