Patent ID: 6686708
Filing Date: 2004-02-03
Classification: H01J,H04N

Abstract:
A color display device comprising a cathode ray tube having a display screen, means for generating at least one electron beam, a vertical deflection unit for generating deflection fields for deflecting the at least one electron beam across the display screen, a vertical deflection current source producing a vertical deflection current through the vertical deflection unit, and magnetic field-generating means at or near a display screen-facing end of the deflection unit to reduce raster distortions, the magnetic field-generating means comprising correction coils and means for supplying said correction coils, in operation, with a correction current, wherein the ratio between the correction current and the vertical deflection current is a function of the vertical deflection and is less for full vertical deflection (N or S) than for half vertical deflection (0.5 N or 0.5 S).