Internal Light‐Extraction Layers with Different Refractive Indices for Organic Light‐Emitting Diodes

Abstract

High‐performance organic light‐emitting diodes (OLEDs) require a light‐extraction layer either inside or outside the device. Herein, transparent metal oxides (MOs) of various refractive indices are inserted between the anode and glass as internal light‐extraction layers to improve the efficiency of the OLED device. Optical simulations are performed to reveal the optimal thicknesses for the light‐extraction layer of metal oxides of various refractive indices. Light‐extraction layers of metal oxides with optimized thickness are then used in OLED devices to evaluate the performance of devices. The device with the higher refractive index MO light‐extraction layer tends to show better device performance. Although the internal light‐extraction layer is inserted, the current flow in the device and the color coordinate variation depending on the viewing angle do not change significantly. These results are helpful in the development of optimized internal light‐extraction layers for individual colors and in the development of OLED displays with optimized light‐extraction layers for each pixel.

Machine Learning Algorithm for Artificial Intelligence-Based Precise Structural Modeling in Organic Light-Emitting Diodes

“…The vertically stacked thin layers inherently generate a microcavity effect that governs interference phenomena under electrical operation. Hence, controlling layer thickness and selecting appropriate organic materials are crucial to avoid light loss through destructive interference and attain the desired emission color and high efficiency. − However, the conventional optimization process, which involves extensive experimentation with a wide range of new materials and numerous layers, is costly and time-consuming. There is great promise in utilizing artificial intelligence (AI)-based research methodologies to address these challenges and streamline the OLED material and device development process.…”