The thin codoped layer with a red emission in the sky blue emitting layer of the white OLED can eliminate trapping effect from dopant and reduce driving voltage by 2.3V due to enhancement of recombination current. The best white OLED in this paper exhibited 243 cd/m(2) at 4.5V, with a luminous efficiency of 8.2 cd/A and a power efficiency of 5.71 lm/W by using conventional fluorescent materials. The variation in CIE coordinates from 243 to 14000 cd/m(2) is (-0.009, -0.001).