Inkjet‐Printed, Flexible Full‐Color Photoluminescence‐Type Color Filters for Displays

Abstract

Photoluminescence‐type color filters (PLCFs) are supposed to offer vivid colors and higher power efficiency for modern displays by removing absorption losses of the conventional color filters (CFs). Inkjet printing (IJP) is a versatile and low‐cost method to pattern color converters. But uniformity of the patterns is a big concern. Poor photoluminescence stability is also problematic, especially for the perovskite nanoparticles (PNPs) and quantum color converters. Herein, a porous polymer film (PF) is deployed as a template for IJP. The capillary effect of sub‐micron pores in the PF modifies the rheological process of ink spreading that eliminates the coffee‐ring effect and simultaneously provides photoluminescence (PL) stability. A high‐quality green PNP, and red quantum rod (QR) based CF array onto the PF is successfully printed. A liquid crystal display (LCD) deploying this full‐color PF CFs is demonstrated. Color gamut of the device could reach 96.9% of BT2020. The PF CFs show good PL stability for more than 218 days. Furthermore, the fabricated PF CFs possess great flexibility, and any chromaticity and brightness change after 10 000 times of folding were not observed. Thus, the proposed CF using the PF is highly suitable for flexible display and photonics components.