Analysis of light-extraction efficiency according to the size of random nanostructures for OLED

Abstract

OLED emits light through the electroluminescence phenomenon (production of light by an organic com-pound in response to an electric current). Light generated in the organic material undergoes attenuation owing to reflection from the metal and light loss due to refraction while passing through the ITO and glass substrate, thereby reducing the efficiency and lifetime of the light extraction. In this study, the refraction of random nanostructures was used as a light-extraction technology to minimize light attenuation and extract more light outward. More-over, experiments were conducted to increase the light-extraction efficiency of the internal loss light with high light loss. To obtain optimal light-extraction conditions, a two-step simulation was performed according to the width and depth of the nanostructures. Based on the results, a sample glass-panel was fabricated, and the light-extraction efficiency was verified.