Highly Efficient OLEDs

Chapter 6Efficiency Enhancement of Organic Light‐Emitting Diodes Exhibiting Delayed Fluorescence and Nonisotropic Emitter Orientation

Tobias D. Schmidt and Wolfgang Brütting

University of Augsburg, Institute of Physics, Augsburg, 86135, Germany

6.1 Introduction

In 1963 the first observation of electroluminescence (EL) of a 5 mm thick anthracene crystal was presented by Pope et al. [1]. Thereafter, it took more than 20 years until Tang and van Slyke demonstrated the first efficient, low‐voltage‐driven, thin film organic light‐emitting diode (OLED) in 1987 [2]. Three years later the first solution processed polymer‐based OLED was developed by Burroughes et al. [3] and therewith the starting signal for a new, rapidly growing field of research had ...