| 摘要 |
A raster distortion correction circuit for correcting both pincushion distortion and trapezoidal distortion of a raster on a cathode ray tube. A parabolic-shaped signal and a sawtooth-shaped signal, both having frequencies equal to the vertical deflection frequency, are supplied to the correction circuit. The amplitude and polarity of the sawtooth-shaped signal is selectively adjusted, and the adjusted sawtooth-shaped signal is combined with the parabolic-shaped signal and supplied to a current modulator. A horizontal deflecting current flows through the modulator and is thus modulated by the combined parabolic-shaped signal and adjusted sawtooth-shaped signal, the modulated horizontal deflecting current being supplied to a horizontal deflection coil included in the horizontal deflection circuit for the cathode ray tube. The parabolic-shaped signal component corrects the pincushion distortion and the adjusted sawtooth-shaped component corrects the trapezoidal distortion. |
