Light manipulation in organic light-emitting devices by integrating micro/nano patterns.

The demonstration of high efficiency and color tunability has brought organic light-emitting devices (OLEDs) into the lighting and display market. High efficiency is one of the key issues for their commercial applications, for which much effort has been devoted to developing novel materials and device structures. It is well known that around 80% of the generated photons are trapped in OLED structure, so that there is still the greatest scope for significant improvements in its efficiency. This has driven the research towards the integration of micro/nano patterns into device structures that benefit from their abilities in manipulating the generation and propagation of photons. Micro/nano patterns with random or periodic morphologies have demonstrated their effect on the outcoupling of the trapped photons within the device. Moreover, the emitting properties other than the light extraction could be manipulated by introducing the micro/nano patterns. This article reviews the recent progresses in improving the light extraction and manipulating the emission properties of the OLEDs through the introduction of the micro/nano patterns by various fabrication strategies. The light manipulation of the micro/nano patterns in organic photovoltaics is briefly discussed considering its similar working principle and fabrication strategies to that of the OLEDs. [ABSTRACT FROM AUTHOR]