| 摘要 |
PURPOSE:To rapidly switch between stopping operation and an untransmitting state of light and to drop the driving voltage of high frequency based on the voltage control of low frequency by using liquid crystal inverting dielectric anisotropy in accordance with frequency, steadily impressing a high frequency voltage and executing the stopping operation at a high frequency voltage. CONSTITUTION:Since a power source 14 generates an output, but a power supply 15 outputs OV, a light transmitting window is closed. On the other hand, the power source 15 outputs high frequency and its peak is higher than that of the power source 14, so that the stopping operation indicated by the state of the light transmitting window is executed. In this case, a part generating a voltage difference with high frequency between main electrodes 9, 10 in the light transmitting window based on the low frequency voltage of the power source 14 is turned to a light transmitting state and a part having a small voltage difference or no voltage difference is turned to the non-transmitting state to form a stopped state. The stopping operation is rapidly executed. When the power source 14 continues the output and the output of the power source 15 is turned to '0', the light transmitting window is rapidly closed. |
