Triolo Claudia, Lorusso Antonella, Masi Sofia, Mariano Fabrizio, Della Torre Antonio, Accorsi Gianluca, Arima Valentina, De Leo Stefano, Rinaldi Rosaria, Patané Salvatore, Mazzeo Marco
Department of Civil, Energy, Environmental and Materials Engineering (DICEAM), Mediterranean University, Via Zehender, Loc. Feo di Vito, Reggio Calabria 89122, Italy.
Department of Mathematics and Physics "Ennio De Giorgi", University of Salento, Via per Arnesano, Lecce 73100, Italy.
ACS Photonics. 2025 Apr 10;12(5):2413-2422. doi: 10.1021/acsphotonics.4c01956. eCollection 2025 May 21.
The understanding and management of the optical behavior of dielectric/metal/dielectric (DMD)-based electrodes are crucial for the design of fully transparent OLEDs. Specifically, the chromatic stability with the viewing angle of white OLED emission remains an important issue due to the angle dependence of internal reflection at the organic/electrode interface as the wavelength varies. The purpose of the present work is to provide a complete analysis of the optical behavior of DMD structures by Variable Angle Spectroscopic Ellipsometry in order to optimize the transmittance of DMD-based transparent white OLEDs over a wide viewing angle. The analysis of the optical modes contributing to power dissipation reveals that the reduction of plasmonic and waveguided modes is related to the antireflection properties of the DMD electrode. This results in a simultaneous significant improvement in the absolute value of the transmittance across the full visible spectral range and in the color stability of white OLED emission over a wide viewing cone of 120°, thus paving the way for a new generation of transparent white lighting sources.
理解和管理基于介电/金属/介电（DMD）的电极的光学行为对于全透明有机发光二极管（OLED）的设计至关重要。具体而言，由于随着波长变化，有机/电极界面处的内反射具有角度依赖性，白色OLED发射的色稳定性随视角变化仍然是一个重要问题。本工作的目的是通过可变角度光谱椭偏仪对DMD结构的光学行为进行全面分析，以便在宽视角范围内优化基于DMD的透明白色OLED的透射率。对导致功率耗散的光学模式的分析表明，等离子体模式和波导模式的减少与DMD电极的抗反射特性有关。这导致在整个可见光谱范围内透射率绝对值的同时显著提高，以及在120°的宽视角锥内白色OLED发射的颜色稳定性提高，从而为新一代透明白色照明光源铺平了道路。
