| 摘要 |
PURPOSE:To attain effective utilization of pattern by selecting the aspect ratio of a display part of a display device the same as that of a displayed pattern so as to select a 4:3 pattern and the display pattern and to display them thereby displaying widely the display pattern and displaying a sub picture in case of the 4:3 pattern. CONSTITUTION:When an input signal is a display pattern signal, if the signal is displayed on the display device 19 without any processing, the pattern is expanded vertically by the blank existing upper/lower part of the pattern by a vertical amplitude control circuit 17, since a pattern expanded laterally is obtained. When an input signal is a 4:3 pattern signal, a pattern expanded laterally is displayed on the display device 19. In expanding vertically the same as the case with the video pattern signal, since the upper/lower picture is missing, the pattern is compressed horizontally by a time compression circuit 15. A control signal is fed to each circuit from a control signal generating circuit 18 to attain horizontal compression and vertical elongation in response to the input signal. In displaying the 4:3 pattern, although a blank exists at the left/right side of the pattern, a sub video signal is also inputted and the main pattern is biased to the left by the signal switching circuit 34 and the sub picture is displayed to display the remaining part on the excess part through the changeover. |
