| 摘要 |
In a color video display device, such as a television receiver or a monitor associated with a color video tape recording and reproducing apparatus, and which is responsive to a composite color video signal including a luminance component and a chrominance component containing a chrominance signal, a burst signal and a chrominance reference portion of a vertical interval reference (VIR) signal; a hue-correction circuit is provided for dynamic correction of chrominance phase errors. The hue correction circuit includes a phase comparator that provides an output in response to the phase difference between the burst signal and the chrominance reference portion of the VIR signal, an oscillator for providing a continuous wave at the frequency of the burst signal, a controlled amplifier acting on the luminance component and having its gain controlled by the output of the phase comparator to provide a correction signal, and a phase modulator for adjusting the phase difference between the chrominance signal and the continuous wave signal in response to the correction signal. The phase comparator can include first and second sample-and-hold circuits for sampling the chrominance phase during the burst signal and during the chrominance reference portion of the VIR signal, respectively. The hue correction circuit can also include a clamp for clamping the output of the controlled amplifier to a reference level during the burst signal.
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