Convergence correction circuit for cathode ray tube

A dynamic convergence apparatus for a cathode ray tube having an electron beam generating means for generating first, second, and third electron beams, comprising:

• a first pair of convergence plates arranged such that said second electron beam passes between the convergence plates;
• a second pair of convergence plates arranged such that said first electron beam passes between one of said first pair of convergence plates and one of said second pair of convergence plates and said third electron beam passes between the other of said first pair of convergence plates and the other of said second pair of convergence plates;
• means for generating a DC voltage applied to said first pair of convergence plates;
• means for generating a convergence voltage having a first voltage waveform modulated by a parabolic signal with a horizontal deflection frequency and a parabolic signal with a vertical deflection frequency and a second voltage waveform of a parabolic signal of said vertical deflection frequency added to a horizontal retrace interval of said first voltage waveform;
• and
• means for supplying said convergence voltage to said second pair of convergence plates, said means for supplying including a series circuit of a capacitor, and a parallel circuit of a diode and a resistor, wherein a connection point of said capacitor and said parallel circuit is connected to said second pair of convergence plates and another end of said parallel circuit opposite to said connection point is connected to a reference voltage source.