| 摘要 |
PURPOSE:To easily perform a screen distortion correction for the horizontal parallelogram distortion of a screen and to unnecessitate an individual distortion correcting circuit by superposing a saw-tooth distortion correcting signal proportional to vertical deflection current to a horizontal phase adjusting circuit. CONSTITUTION:A saw-tooth wave voltage proportional to vertical deflection current is taken out from a vertical output circuit 9 and inputted to a screen distortion correcting means 10 so as to improve the horizontal parallelogram distortion. The screen distortion correcting means 10 converts the saw-tooth wave voltage into a screen distortion correcting signal corresponding to the horizontal parallelogram distortion. Then, horizontal phase shift amounts are changed in a saw-toothed shape by superposing the output of the correcting signal to a horizontal phase correcting voltage VS being the output of a frequency-voltage conversion circuit 7 and supplying the superposed output to a constant current circuit 8. That is, since the saw-tooth distortion correcting signal is generated by providing a difference between a reference signal obtained by converting the saw-tooth voltage detected by the vertical deflection current and a comparison signal, the position of horizontal picture is changed in the saw-tooth shape in vertical periods by superposing the output of the horizontal phase adjusting signal. |
