| 摘要 |
PURPOSE:To realize an absolutely correct color ratio by using a decoder circuit selecting a special output for the 2nd control circuit in response to the combination of an inputted superimposing video information signal. CONSTITUTION:The 2nd control circuit applying superimposing video information signals R', G', B' to an output terminal of a transistor 17 of the output stage of an amplifier circuit 22 is used for a decoder 24 selecting a special output in response to the combination of the superimposing video information signals R', G' and B' to be inputted. One outut is selected through the combination of the three inputs R', G' and B' and the color ratio of a ratio adjusting circuit 26 is decided absolutely to the three outputs, then the absolutely correct color ratio is realized to an optional combination of the signals R', G' and B' so as to obtain an accurate composite video signal. |
