Patent ID: 6501238
Filing Date: 2002-12-31
Classification: H01J,H04N

Abstract:
An apparatus for correcting a mis-convergence and geometric distortion in a deflection yoke using a variable resistance, the apparatus comprising:a conical-shaped coil separator including a neck portion and a screen section; an upper horizontal deflection coil and a lower horizontal deflection coil installed to be electrically connected to each other at an upper and lower portions of inner periphery of the screen portion in the coil separator; a left vertical deflection coil and a right vertical deflection coil installed to be electrically connected to each other at an upper and lower portions of outer periphery of the screen portion in the coil separator; a conical-shaped ferrite core installed at outer periphery of the screen portion in the coil separator to enhance a magnetic field of the vertical deflection coil; a plurality of comma-free coils installed at the neck portion of the coil separator to be electrically connected to the vertical deflection coil for generating a pin-cushion magnetic field, thereby canceling a barrel magnetic field generated by the left and right vertical deflection coils; a distortion adjusting portion for correcting geometric distortion on a screen by adjusting a relative current flowing in the left and right vertical deflection coils and thereby, adjusting a relative magnetic field in the left and right sides; a first convergence adjusting portion for correcting a vertical mis-convergence on a screen by adjusting a relative current flowing in the comma-free coils at the middle left portion and the middle right portion and thereby, adjusting a relative magnetic field in the left and right sides; a second convergence adjusting portion for correcting a horizontal mis-convergence on a screen by adjusting a relative current flowing in the comma-free coils at the upper portion and the lower portion and thereby, adjusting a relative magnetic field in the upper and lower sides; and a vertical center raster mis-convergence adjusting portion, comprising variable resistance connected to the comma-free coils in parallel, and fixed resistance connected to a common contact point of the left and right comma-free coils and a moving electrode of the variable resistance.