High color purity emission from quantum dots by optimizing the full width at half the maximum and optical density to blue light

In this paper, we got wide color gamut of quantum dot (QD) films by optimizing the spectra width and optical density (OD) of quantum dots. The specific methods to achieve the following: QD R: one layer of color filter R film was coated below the QD R layer. QD G: one layer of yellow‐green film was coated below the QD G film. By a structure optimal design, we got wide color gamut up to 99.2% BT2020 (equal to 132.86% NTSC) in Cd‐based QD and 93.6% BT2020 (equal to 125.35% NTSC) in Cd‐free QD. Furthermore, the gamut of QD display will continue to be improved by continuous refining the structure of QD display. The figures describe a scheme that the quantum dot (QD) display relies on a multi‐layer design to achieve high purity. The main idea is to place a cut layer below the QD layer to absorb excess light. All the work focuses on the development of efficient cut layers and highly feasible structure.