| 摘要 |
<p>PURPOSE:To make the ratio of level of a synchronizing signal to a picture signal constant by adding a digital picture signal to a part corresponding to a scanning between horizontal and vertical synchronizing signals represented by the digital code signal of a prescribed bit number. CONSTITUTION:At first, a trigger signal is inputted to a picture memory 1, from which a digital picture signal is outputted from the picture memory 1. On the other hand, a synchronizing signal is inputted to a multiplexer 2, where the signal of 11111 corresponding to an H level and a signal of 00000 corresponding to an L level are selected and the result is outputted as a digital synchronizing signal. The digital synchronizing signal and the digital picture signal are added by an adder 3, from which a 7-bit digital composite picture signal is obtained. The picture signal obtained by the adder 3 is subjected to D/A conversion be a D/A converter 4 and the result is outputted as an analog composite picture signal.</p> |
