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Holographic display, which can completely reconstruct phase and amplitude information, is considered as an ideal true three‐dimensional display technology. In this work, liquid crystal doped with perovskite (CsPbBr3) works as the photorefractive material and forms diffraction grating under the interference light beams. The dependences of diffraction efficiency and response time on doping concentration, recording beam power and applied voltage are investigated. A maximum first‐order diffraction efficiency of 18% has been achieved under a low electric field intensity of ~0.5 V/μm and the shortest grating build up time is as low as 5.5 ms. The system can realize a real‐time dynamic display with 60 Hz refresh rate.

We propose the use of a nematic liquid crystal (LC) doped with quantum dots (QDs) to realize a color 3D holographic display. The material has super large optical nonlinearity and could achieve a fast response time ~ 8.46ms. The constructed 3D display shows images at different depths and vivid RGB images at a video refresh rate.

A nondoped full‐exciplex approach is applied in white organic light‐emitting diodes (WOLEDs). Both the blue emission and yellow emission are from exciplex, which makes it possible to exceed the 25% internal quantum efficiency limit of normal fluorescent OLEDs via reverse intersystem crossing from triplet to singlet states because of the small energy gap between them. White emission can be realized by simply stacking the blue and yellow exciplex materials because the same acceptor material is used in the emitting systems. And a two‐color WOLED with an external quantum efficiency (EQE) of 6.11% is demonstrated, exceeding the efficiencies of the exciplex‐based blue and yellow monochrome devices. The higher efficiency is attributed to redistribution of the exciplex excitons, which suppresses the exciton concentration quenching at the emission interface. By adopting a quantum‐well‐like structure, the EQE can be further improved. This approach sheds light on the simple fabrication of high‐efficiency WOLEDs in the future. A high‐efficiency white organic light‐emitting diode based on all‐exciplex emission is demonstrated with a simple nondoped structure. The efficiency is higher than each individual monochromatic device, which is attributed to the redistribution of excitons and suppressed triplet–triplet annihilation. A quantum‐well‐like structure can further improve the efficiency by expanding the exciton recombination zone.