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Aging is still the most challenging issue for organic light‐emitting diodes (OLEDs), which causes the image‐sticking artifacts on active‐matrix organic light‐emitting diode (AMOLED) displays and limits their lifetime. To overcome this demerit, an aging model is necessary to compensate for aging artifacts. In this paper, we present a unified OLED aging model, which combines three feasible modeling approaches of OLED degradation, namely, data‐counting, electro‐optical, and correlation methods. The model can be used to predict the efficiency decay of OLED pixels during operation. It mitigates weaknesses and limitations of each of these three models and deploys their strengths, respectively. In the first aging stage, the data‐counting model is prioritized, and in the later stages, it is calibrated using the correlation model. The dependency of the efficiency decay on the operation point of OLED is covered by the electro‐optical model. The unified model is based on both phenomenal and physical effects. It delivers more reliability to determine an OLED's degradation over a long‐term operation and a wide operation range like current amplitude and/or temperature range. The unified aging model applies to either an analog or a digital driving scheme. A corresponding compensation based on the aging model can be applied for extending the AMOLED lifetime. [ABSTRACT FROM AUTHOR]

Irreversible chemical reactions are responsible for limited operational lifetime of organic light‐emitting devices (OLEDs). These reactions are triggered by highly reactive polaron pairs present in the emissive layer of OLEDs. Fast recombination of the polaron pairs is, therefore, crucial for slow degradation and high stability of OLED materials. Here, a study of the formation and annihilation of close polaron pairs in binary mixtures of wide bandgap hosts and a series of blue‐phosphorescent Ir(III) complex dopants, including two novel compounds, is reported. OLED devices containing doped light‐emitting layer are fabricated, and their operational lifetimes are estimated. Although inaccessible in solid films, charge recombination kinetics inside the polaron pairs is measured in liquid solutions using nanosecond laser flash photolysis. Multiscale computer simulations are applied to connect experimental results in different media and predict recombination rates in the device, with proper account taken of the inner‐ and outersphere reorganization in nonpolar materials. Predicted rates correlate with measured operational lifetimes, which demonstrates the key role of polaron pairs in the OLED degradation process. The developed methodology is useful for the rational design of novel OLED materials with higher efficiency and stability. [ABSTRACT FROM AUTHOR]

It is a proposal for preventing image sticking of OLED using deep learning based object detection. It was able to detect transparent objects superimposed on complex backgrounds and we got 92% detection performance. The burn‐in pixels can be detected in real time and the luminance can be adjusted to 80%. [ABSTRACT FROM AUTHOR]

This work presents a new pixel circuit using low‐temperature polycrystalline‐oxide thin‐film transistors (LTPO TFT) for active‐matrix organic light‐emitting diode (AMOLED) displays. The proposed circuit can compensate for the threshold voltage (Vth) variations of driving TFT. Moreover, the degradation of OLED can be reduced to a certain degree. The simulation results demonstrate that the current of OLED is independent of the Vth shifting and changes as the OLED threshold voltage. That means this LTPO circuit can improve the stability of displays. [ABSTRACT FROM AUTHOR]