| 摘要 |
PURPOSE:To prevent exhaustion of a battery through utilization of solar cell by forming the driver for a liquid crystal panel furnished at a window from a solar cell and means to generate the driving voltage in compliance with the supply voltage to the panel. CONSTITUTION:If a control switch 41 is opened to shut an oscillator 42 from a solar cell 30, a drive voltage generator circuit 40 is held out of operation to retain a liquid crystal panel transparent, that allows sufficient taking-in of the sun beam into the car cabin. When this switch 41 closed, the solar cell 30 supplies power to actuate the ascillator 42. If, at this time, high temp. of the cabin causes a switch 44b closed by a relay 44 and a room temp. sensor 43, the abovementioned drive voltage generator circuit 40 supplies the drive voltage to the liquid crystal panel to put it in dynamic diffused state, that will shut the cabin from irradiation of sun beam. Thereby use of the battery is not required for this purpose to contribute to preventing exhaustion of the battery. |
