Bioinspired ultrathin photonic color convertors for highly efficient micro‐light‐emitting diodes

Abstract Pixelated color convertor plays an immensely important role in next‐generation display technologies. However, the inherent randomness of light propagation within the convertor presents a formidable challenge to reconcile the huge contradiction between excitation and outcoupling. Here, we demonstrate a bioinspired photonic waveguide pixelated color convertor (BPW‐PCC) to realize directional excitation and outcoupling, which is inspired by an insect visual system. The lens array of BPW‐PCC enables a focusing photonic waveguide that guides the excitation light and converges it on colloidal quantum dots; the directional channel provides a splitting photonic waveguide to enhance the outcoupling of photoluminescence light. Consequently, the excitation and outcoupling efficiency can be simultaneously improved at this judiciously designed pixelated color convertor with a thickness of 50 μm. By this strategy, ultrathin BPW‐PCCs with 4.4‐fold enhanced photoluminescence intensity have been demonstrated in micro‐light‐emitting diode devices and achieved a record‐high luminous efficacy of 1600 lm W −1 mm −1 , opening a new avenue for efficient miniaturized displays.