| 摘要 |
PROBLEM TO BE SOLVED: To control the power consumption during power failure, and reduce the capacity of a backup power source. SOLUTION: An LCD brightness control device 13 of a living room information terminal equipment 1 whose power is supplied from a commercial power source 2 normally, and whose power is supplied from a backup power source 15 during power failure, is equipped with; an optical sensor 20 which watches the brightness of the place where an LCD 10, which is irradiated by a backlight 11 whose power supply is provided through an inverter for backlight 12, is placed; a control circuit 21 which reduces the brightness of the LCD backlight to the brightness necessary to confirm the display content of the LCD, when the optical sensor judges the brightness to be too dark; and a power failure detection circuit 22 which outputs the power failure detection signal that adjusts the brightness of LCD backlight to the brightness necessary to confirm the display content of LCD by the control circuit 21. Thus, the power consumption of an inverter for backlight is controlled and the capacity of a backup power source is reduced. |
