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US 4,225,804 AGranted
Cathode ray tube coma correction device
AssigneeGTE Sylvania Incorporated
InventorsJohan Bekaert, Raymond Goos
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AssigneeGTE Sylvania Incorporated
InventorsJohan Bekaert, Raymond Goos
Estimating the term…
In a self-converging inline cathode ray tube assembly having a convergence electrode with a flat base and a central and two outer apertures formed for passage of electron beams, a pair of substantially flat sheets of ferromagnetic material having a substantially U-shaped configuration are disposed in mirror-image relationship intermediate the central aperture and each one of the outer apertures with the open portion of the U-shaped configuration directed toward the outer apertures whereby the deflection field of the electron beam passing through the central aperture is relatively strengthened and the deflection fields of the electron beams passing through the outer apertures are relatively weakened to provide an enhanced vertical and horizontal scanning raster for the cathode ray tube.
In a self-converging cathode ray tube assembly having an inline cathode ray tube with a convergence electrode having a substantially flat base and a central aperture aligned in a plane with two outer apertures formed to provide passageway for electron beams, the improvement characterized by two substantially flat sheets of ferromagnetic material affixed in planar relationship to said flat base and disposed in mirror-image relationship intermediate said central aperture and each one of said two outer apertures, each of said sheets of ferromagnetic material having a substantially U-shaped configuration with the open portion thereof directed toward one of said outer apertures of said convergence electrode whereby said ferromagnetic sheets provide a weakening effect upon the vertical deflection field for the electron beams passing through said two outer apertures and a strengthening effect upon the vertical deflection field for the electron beam passing through said central aperture.
In a device for correcting horizontal and vertical misconvergence in a cathode ray tube of the inline type having a convergence electrode with a substantially flat base and a central and two outer apertures aligned along an x-axis and formed for passage of electron beams therethrough, the improvement comprising a pair of flat sheets of ferromagnetic material affixed in planar relationship to said flat base of said convergence electrode and disposed in mirror-image relationship intermediate said central aperture and each one of said two outer apertures with each of said sheets having a substantially U-shaped configuration and the open-portion thereof directed toward one of said two outer apertures.
Dependencies are inferred from the claim text.