The effect of blue pixel aging on AMOLED color shift

The color shift problem caused by OLED aging has always been a hot issue in the field of OLED display. The difference of pixel attenuation rate of different colors will seriously affect the display effect of the device. In this paper, image signal generators and lifetime testers were used to test the brightness and color coordinate changes of OLED display under different initial brightness during the aging process. In addition, the causes of white dot color shift and the trajectory of color shift were explored. The research results show that the reduction of blue light ratio caused by the rapid decay of blue pixel efficiency is the cause of the color shift of the white picture, and the color shift trajectory from the white light area to the yellow light area causes the white picture to be yellowish. In order to correct the color shift of the white screen, the thickness of the HIL (hole injection layer) is optimized. The study found that when the thickness of the hole injection layer is 1070 Å, the chrominance efficiency of blue pixels can be kept in the peak area, and the improvement effect is significant, the slope of the color shift locus is reduced to 1.26, the color shift value is reduced from 0.0051 to 0.0017, and the JNCD is less than one.