| 摘要 |
PROBLEM TO BE SOLVED: To display video that is partially expanded with a simple structure without increasing current consumption by selecting the resonance frequency of a sigmoid correction condenser and a horizontal deflecting coil specific times as large as a horizontal deflecting frequency. SOLUTION: When the resonance frequency of a sigmoid correction condenser CS and a horizontal deflecting coil LDY is selected 0.6 to 1.1 times as large as a horizontal deflection frequency, horizontal deflecting current becomes a signal waveform that superimposes a cosine waveform on a sawtooth waveform. That is, in a horizontal deflection circuit 4, the resonance frequency of the coil LDY and the condenser CS is set to 0.6 times as large as a horizontal deflecting frequency, and a resonance cycle that corresponds to the resonance frequency is set to two times as large as a horizontal deflecting cycle. A video signal is horizontally deflected by the horizontal deflecting current that is made when the cosine waveform is superimposed on the sawtooth waveform. Through this, the video signal is expanded and displayed on a cathode-ray tube because the central part of a video period that corresponds to the center of the cosine waveform is expanded. |
