Simultaneously improving color purity, stability, and health-friendliness of OLEDs via optimally designed color filters

The widespread application of high-performance organic light-emitting diodes (OLEDs) remains hampered by persistent challenges, such as enhancing color purity, ensuring long-term stability, and mitigating health risks. While existing methods have made progress in addressing specific challenges, achieving concurrent improvements remains difficult. In this paper, we develop an optical model for OLEDs integrated with optimally designed color filters (CFs) and propose systematic CF optimization strategies to address these challenges simultaneously. A series of CFs compatible with OLEDs of varying peak wavelengths were designed to enhance color purity, stability, and health-friendliness while preserving intrinsic device properties, such as microcavity structures and material composition. The optimized CF structure comprises high-reflectivity films, a spacer layer, and a traditional interference filter. Results demonstrate that green OLEDs incorporating the optimized CF increase color purity from 0.899 to 0.992 in the forward direction, approaching the theoretical maximum, with only a 1.13% intensity loss at the peak wavelength. Furthermore, under multiple viewing angles, color purity improves by ∼0.1, and the effective viewing range expands from 40° to 50°, enhancing angular performance. RGB-pixel OLEDs with optimized CFs exhibit a color gamut expansion from 90.9% to 95.8% NTSC, paving the way for more vivid and realistic color reproduction. Notably, the CFs suppress ultraviolet-induced degradation by maintaining <5% transmittance below 450 nm, thereby improving stability and reducing exposure to high-energy blue light, which enhances health-friendliness. These findings advance the development of high-performance OLEDs and establish a framework for future optimization.