| 摘要 |
PURPOSE: A liquid crystal display apparatus having large screen brightness control domain makes it possible to control the brightness of the entire domain from a back light off to a maximum value, thereby reducing the power consumption. CONSTITUTION: The liquid crystal display apparatus provides a back-light cool cathode fluorescence lamp(CCFL)(185) with the high voltage alternating current of a maximum value and controls the approval time ratio of the alternating current, provided to the back-light cool cathode fluorescence lamp(CCFL)(185), according to brightness control. A DC/AC inverter circuit(171), for providing the back-light cool cathode fluorescence lamp(CCFL)(185) with the alternating current of the high voltage, controls the on/off duty ratio of a switching circuit(172) for generating the alternating current according to brightness control. A high voltage converter(173) provides the back-light cool cathode fluorescence lamp(CCFL)(185) with the alternating current of high voltage when the switching circuit(172) is in the on state. |
