Dynamic convergence device for color cathode-ray tube

摘要

A dynamic convergence device in a color cathode-ray tube has two pairs of confronting high- and low-voltage electrode plates disposed in a color cathode-ray tube bulb and arranged such that a central electron beam will pass between the high-voltage electrode plates and side electron beams will pass between the high-voltage electrode plates and the low-voltage electrode plates. A first parallel-connected circuit is composed of a first resistor and a first diode which are connected between the low-voltage electrode plates and a high DC voltage source. A second parallel-connected circuit is composed of a second resistor and a second diode which are connected between the high-voltage electrode plates and the high DC voltage source. A convergence voltage source generates a convergence voltage which is composed of a vertical parabolic wave voltage added to a modulated voltage in horizontal blanking intervals thereof which is produced by amplitude-modulating a horizontal parabolic wave with a vertical parabolic wave. A first capacitor is connected between the convergence voltage source and the low-voltage electrode plates or the high-voltage electrode plates, and a second capacitor is connected between the low-voltage electrode plates or the high-voltage electrode plates and ground.