Color picture tube apparatus
AssigneeKabushiki Kaisha Toshiba
InventorsKenichi Kobayashi, Hiroyuki Koba, Naoto Nakamura
Life of this patent
Estimating the term…
Abstract
A color picture tube apparatus comprises a color picture tube including an envelope having a phosphor screen excited by a plurality of electron beams, and deflection means generating horizontal deflection field and barrel type vertical deflection field for the beams, including non-linear magnetic field correction means generating an additional pin-cushion type magnetic field in the vertical field to have preferably convergence characteristics such that vertical direction coma errors can be appropriately corrected throughout every portion of the vertical axis on the screen, whereby high-definition color images can be obtained thereon.
Claims16
A color picture tube apparatus, comprising:
- a color picture tube including an envelope with a panel therein, a phosphor screen disposed inside the panel, and an in-line type electron gun generating a center beam and a pair of side beams for exciting the phosphor screen to emit light;
- and
- defelection means generating horizontal and vertical deflection magnetic fields for deflecting the electron beams from the electron gun to form respective rasters, the deflecting means including means for generating a barrel type vertical deflection magnetic field and non-linear magnetic field correction means for generating an additional pin-cushion type magnetic field added to the vertical deflection magnetic field for vertically adjusting the position of the rasters produced by the side beams to the position of the raster produced by the center beam.
A color picture tube apparatus comprising:
- a color picture tube including an envelope with a panel therein, a phosphor screen disposed inside the panel, and an in-line type electron gun generating a center beam and a pair of side beams for exciting said phosphor screen to emit light;
- deflection means including including first deflection means for generating a pin-cushion type horizontal defelection magnetic field to deflect the electron beams in a horizontal direction, and second deflection means for generating a barrel type vertical deflection magnetic field to deflect the electron beams in a vertical direction;
- deflection magnetic field correction means including two pairs of sub-coils for generating a nonlinear correction magnetic field for vertically adjusting the position of the rasters produced by the side beams to the position of the raster produced by the center beam;
- deflection current supplying means including first deflection current supplying means electrically connected to the first deflection means to supply first deflection current to the first deflection means and second deflection current supplying means electrically connected to both of the second deflection means and deflection magnetic field correction means to supply second deflection current to both of the second deflection means and deflection magnetic field correction means;
- and
- means for nonlinearly adjusting the current in said correction means in accordance with the deflection current in the vertical direction.
Dependencies are inferred from the claim text.