| 摘要 |
PURPOSE:To avoid the resolution from being deteriorated apparently even with a magnified screen, by converting a luminance signal into a double frequency luminance signal and applying it to a matrix circuit. CONSTITUTION:A signal video-detected is separated into a luminance signal Y and a chroma signal Cr at a separation circuit 7. The separated luminance signal Y is applied to a double frequency converting circuit 6, where the signal is converted into a double frequency luminance signal Y and applied to a matrix circuit 8. As to the chroma signal Cr, a chroma signal converted into low and high frequencies at a multiplication circuit 17 is obtained, and the chroma signal of low-frequency-conversion only is picked up through a low pass filter 18 and applied to the matrix circuit 8 via a double frequency conversion circuit 19, a low pass filter 20, a multiplication circuit 21, a band pass filter 22 and a demodulation circuit 9. |
