| 摘要 |
PURPOSE:To increase the lifetime of a display panel in a simple and assured way, by inverting the polarity which is applied to both electrodes of the liquid crystal of the display panel with use of a video signal inverting circuit and an inverting circuit of the voltage applied to the common electrode of the video signal of a receiving channel selecting device. CONSTITUTION:When a switch SW1 is pushed in case a channel 1 is selected, the input is set at a low level at the area corresponding to the channel 1 of a channel selection control part 1. Then the voltage at the output part of the part 1 is controlled, and a channel is selected. The output of an AND circuit 2 is set at a low level since at least one of the inputs of the circuit 2 is set at a low level. Thus the circuit 2 inverts the output of an FF-3. On the other hand, a video signal is applied to a terminal 11 and then supplied to the amplifiers 4 and 5. Then the amplifier 4 feeds the output to a horizontal driver 8 via a transmission gate 6 with the same phase; while the amplifier 5 feeds the output to the driver 8 via a transmission gate 7 with the opposite phase respectively. The voltage having the positive and negative polarities when viewed at the edge side of a common electrode is applied to a panel 10. |
