The color conversion of LCD backlight includes blue light excitation YAG yellow powder, blue light excitation β-SiAlON+KSF red powder, and blue light excitation red green quantum dot fluorescence film, etc. In the digital dimming mode, the brightness change trend of the three color conversion schemes under different current duty cycle conditions is basically linear, but the color coordinate change trend is significantly different. Blue light excitation β-SiAlON+KSF red powder conversion scheme has the largest difference in color coordinate changes among the three models with current variation, and the change in red is more significant than that in green. The color coordinate change of the blue light excited red green quantum dot conversion scheme is between the other two schemes, and the green change is more significant than the red one. After analysis, the difference in color coordinate changes is related to the difference in quantum excitation efficiency of red and green powders. By shortening the afterglow time of KSF powder and the dimming cycle time of the driving current, the“red explosion”phenomenon can be eliminated.