Simple-structure color-tunable fluorescent organic light-emitting devices with chromaticity difference beyond five-step McAdam ellipses

Abstract

Currently, status lighting, such as signal indication and information coding, is considered as a novel potential application of organic light-emitting devices (OLEDs). Compared to conventional lighting and display applications, status lighting requires tunable colors distinguishable by the human eyes with natural appearances rather than high efficiency. Here, a color-tunable fluorescent OLED (CTFOLED) for status lighting is successfully prepared by using an ultrathin emitting layer consisting of a deep-blue host and a green guest. Through adjusting exciton concentration and forming an island growth induced exciplex interface, the CTFOLED shows a voltage-modulated emission color. Its coordinates change from (0.26, 0.61) to (0.35, 0.50) as the bias voltage increases from 4 to 10 V. The chromaticity coordinates are demonstrated to beyond five-step McAdam ellipses at the neighboring voltages (an interval of 2 V) such that the voltage-modulated color variations are easily distinguishable by the human eye. Finally, it also proposed that the CTFOLED can be used as a status light for presenting three statuses of drinking water: cold, warm and hot. This work paves a way for the application of OLEDs in status lighting.

Near-infrared organic light-emitting materials, devices and applications

“…A welldesigned device configuration can enhance carrier injection and transport, thereby increasing the likelihood of exciton formation. [24][25][26][27] Elaborate choice of host materials and compositional adjustment can affect the exciton distribution profile, and thus bimolecular quenching. Moreover, outcoupling efficiency (OCE) of NIR OLEDs is determined by the refractive indexes and the thicknesses of multilayer structure, light extraction units, and so on.…”

The Influence of Energy Transfer on the Color Temperature Change in Color-Tunable Organic Light Emitting Diodes with Interface Exciplex

“…The color-tunable CT-OLED with a wide correlation color temperature (CCT) can simulate the change of sunlight, which is consistent with the human physiological cycle. In some specific occasions, such as military and medical fields, the demand for the high-performance CT-OLED is very necessary and urgent [9]- [15].…”