有机发光器件的光学调控研究进展

Organic light-emitting diodes (OLEDs) have gained increasing attention in applications of full-color display panels, wearable intelligent electronics and eco-friendly interior lighting. Recently, the innovations of material design, device structure and manufacturing technology have driven the performance of OLED device to reach a new stage in terms of large area, long lifetime, high efficiency and color rendering index. Light out-coupling plays a critical role on the efficiency of electron-photon conversion process, so it is of great importance in developing efficient and stable OLEDs to manipulate light out-coupling and avoid intrinsic loss of photon. In this review, we emphasize the strategies of light manipulation from the perspectives of wavelength dependency, angle sensitivity and compatibility with fabrication process. Various optical loss channels are analyzed, and recent developments of micro/nanostructure-stimulated light out-coupling for OLEDs are overviewed. At last, we introduce our newly developed technique of light manipulation with biomimetic moth-eye nanostructure via soft nanoimprint lithography. This technique obtains extremely high power efficiencies of 123.4 lm·W^-1 and 106 lm·W^-1 for glass and plastic based white OLEDs respectively, as well as current efficiency of 366 cd·A^-1 for green OLED. This technique is expected to accelerate the commercialization of large-scale and low-cost OLED panels, and to inspire new design of advanced device architecture.