| 摘要 |
In a lighting device for a display device, sensor output determination portions determine whether color sensor output signals are greater than or equal to a predetermined threshold. Variable gain amplifiers amplify the color sensor output signals with a predetermined gain. A color control portion performs color control based on post-amplification signal and obtains luminances of three types of LEDs. Constant current circuits and the PWM circuits drive the three types of LEDs in accordance with control from the color control portion. Gains of the variable gain amplifiers are switched in a stepwise manner so as to become higher as the color sensor output signals become lower. Thus, it is possible to perform color control with high accuracy even when darker light is provided.
|
