| 摘要 |
PURPOSE:To straighten a lateral line at the time of viewing from the upper and lower ends of a screen by forming a reset pulse by a 2nd addition output to apply Miller integration based on a 1st adder output and the reset pulse thereby obtaining a vertical pincushion distortion correcting waveform. CONSTITUTION:1st adder means 11, 12 rectifies a sawtooth wave of vertical period, adds positive and negative components and 2nd adder means 11, 13 rectifies the sawtooth wave of vertical period and adds the positive components and the component of the inverted negative component. Phase shift means 15, 16 form a narrow pulse synchronously with the horizontal period pulse and the narrow pulse is controlled by an output of the 2nd adder means (triangle wave of vertical period) to form a pulse train having much phase shift at the upper/lower ends of the screen and nearly zero at the center. Then the output of the 1st adder means is used as a voltage to be integrated and the pulse train from the phase shift means is used as the reset pulse, which is fed to an integration 17, where the pulse is subjected to Miller integration. As a result, a sawtooth waveform voltage of horizontal period is obtained as a vertical pincushion distortion correcting waveform is obtained. Thus, the lateral line is straightened by the correction. |
