Nanotextured light modulation for flexible OLEDs with 370% enhanced EQE and angular color stability

Top-emitting microcavity OLEDs (TEOLEDs) exhibit excellent color purity but suffer from severe angular color shifts. To overcome this, we introduce a nanotextured light modulation strategy using a nanoporous film (NPF) and an index-matched optically clear resin (OCR) for encapsulation. The nanotextured NPF enhances light outcoupling while suppressing cavity-induced angular dependence. As a result, the external quantum efficiency (EQE) is enhanced by 370% (from 8.5 to 31.6%), and angular color shift (Δu'v') is reduced by 65.2% (from 0.046 to 0.016). By introducing a nanostructure-based light modulation technology, we have achieved a breakthrough in microcavity OLED performance, simultaneously improving both outcoupling and angular stability. Applied to flexible TEOLEDs, the device exhibits stable optical and mechanical performance under bending. This scalable and effective light modulation design enables highly efficient and color-stable flexible OLED displays for next-generation wearable applications.