| 摘要 |
PURPOSE:To improve resolution and to prevent a picture from flickering by delaying the 2nd horizontal scanning line by a half a one-dot period behind the 1st horizontal scanning line and allowing it to overlap the 1st horizontal scanning line. CONSTITUTION:A video signal for a scan in the 1st field is supplied from an input terminal 8 to a multiplexer 14 directly and a video signal for a scan in the 2nd field is applied to a delay circuit 12. The delay circuit 12 performs delay by a half 0.25musec for a television system which uses 525 scanning lines. The video signal passed through the delay circuit 12 is applied to the multiplexer 14 as well and a counter circuit 13 counts a vertical synchronizing signal VS applied to an input terminal 9 to switch the multiplexer 14 at intervals of one field. A video signal 17 which is shown by black and shifted by a period a half one dot after a video signal 16 shown by white is scanned on one-field scan basis of the 1st scanning line 13, the 2nd scanning line 14 - the (n)th scanning line 15 is inserted between white and white videos on a screen, improving the resolution. In this case, the number of scanning line is increased up to, for example, 819 by widening a band. |
