| 摘要 |
PURPOSE:To obtain an invariably picture of high quality by preventing a blooming state, by suppressing the white side compontents of a profile-corrected signal only when a transient signal in terms of the white side is supplied to CRT excessively. CONSTITUTION:A video signal applied to input terminal 21 is supplied to profile signal shaping circuit 22, which generates a profile-corrected signal. The profile- corrected signal is supplied to white peack signal suppressing circuit 24 suppresses white side high frequency components. The signal applied to input terminal 21, on the other hand, is further supplied to LPF25 to extract low frequency components and white-side high frequency components suppressed are mixed by synthesizing circuit 26. Circuit 24 utilizes the difference in impedance between points a7 and a8 due to the one-off operation of diode D21 to turn on-off according to the collector potential of transistor Q23. Its operation range is set when the signal level of input terminal 21 is high and the white-side transient signal is supplied to CRT excessively. This depends upon resistance values of resistances R33 and R34. |
