| 摘要 |
PURPOSE:To make pedestal levels of two video signals coincident with each other with less number of elements, by comparing the pedestal level of the signal from a video signal processing circuit with a reference voltage, and feeding back the comparison result to the video signal processing circuit. CONSTITUTION:Primary color signals from a video signal processing circuit 100 are inputted to signal switching circuits 15-17. Output signals of switching circuits 15-17 have levels and brightnesses controlled in amplifiers 18-20 and are outputted. The pedestal potential of primary color signals is compared with a reference bias voltage 24 in a comparator 35, and the output of the comparator 35 is fed back to a bright control terminal 14 by a gate pulse applied to an input terminal 36. |
