An optical feedback system for local dimming backlight with RGB LEDs

One of the major issues plaguing RGB LED backlight is color shift. This phenomenon is due to the characteristic changes of each Red, Green, and Blue LEDs as the time and temperature variation. To compensate this variation, many researchers are proposed color control method for the stable color management. However, their method is not suitable for the local dimming backlight because of the light interference between blocks. Therefore, we proposed an optical feedback system for the stable color control regardless of its dimming method. The test results show that our proposed method is very suitable for RGB LED backlights.