| 摘要 |
PURPOSE:To eliminate the need for a detection circuit and a band pass filter by using a part of a noise reduction circuit as a separation circuit of a mixed picture element signal and obtaining a difference signal of a separated mixture picture element signal so as to demodulate a modulated color signal. CONSTITUTION:A signal obtained from a DC recovery circuit 3 is fed to sample- and-hold circuits 41, 42, where the signal is sampled to obtain two kinds of mixed picture element signals from which a reset noise is eliminated. The two kinds of mixed picture signals obtained through separation is added by an adder circuit 13 and becomes a luminance signal through a low pass filter 8. Simultaneously, two kinds of mixed picture element signals are fed to a subtractor circuit 15 via gain control circuits 141, 142 to obtain a difference signal of the both, thereby converting the color signal B or R subject to frequency modulation into a base band signal.
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