| 摘要 |
PROBLEM TO BE SOLVED: To obtain a stable picture quality without burdening a cameraman or an engineer by adopting a prescribed deflecting circuit to automatically correct the secular change. SOLUTION: A deflected waveform 1 is inputted to an attenuator 2. The output of the attenuator 2 and a DC reference voltage 4 are inputted to a comparator 5 to detect the point where an output waveform 3 of the attenuator 2 and the DC reference voltage 4 overlap. An output waveform 6 of the comparator 5 is temporarily stored in a memory 7 in the state free from the secular change of the DC component of the deflected waveform. In accordance with the secular change of the DC component of the deflected waveform, the output waveform 3 of the attenuator 2 and the output waveform 6 of the comparator 5 are changed. Then, the signal from the memory 7 and the changed output waveform 9 of the comparator 5 are inputted to a phase comparator 10 to detect a phase difference 11. The output of the phase comparator 10 is inputted to a deflected wave output circuit 12 as a centering correction signal to perform the correction. |
