Dynamic modulation of ultraviolet (UV) and visible light is important for smart windows, adaptive photonics, and emerging display technologies. Here we report a vertically aligned polymer network liquid crystal (PNLC) platform that enables electrically tunable UV–visible light control with high optical clarity and low operating voltage. Using a negative dielectric anisotropy liquid crystal and optimized UV polymerization, the PNLC device exhibits high transparency in the field-off state (~83% transmittance with ~1.5% haze) and switches to a strongly scattering state (~90% haze) under applied electric fields. Electro-optical switching begins at ~1.5 V μm-1 and saturates near ~3.4 V μm-1, with attenuation governed by field-induced refractive-index mismatch rather than intrinsic absorption. By integrating the PNLC shutter with InP/ZnSe/ZnS QD/NOA composite layers, we demonstrate electrical modulation of quantum dot (QD) photoluminescence (PL) through excitation gating. Green and red QDs emit at ~530 and ~630 nm and show reversible intensity modulation with high modulation depth (~92–97%). The device also exhibits millisecond-scale switching and stable operation over repeated cycles. This architecture establishes a quantum dot liquid crystal display (QD-LCD) concept, offering a pathway toward high-brightness, long-lifetime, and low-voltage photonic and display systems.
Ramadas et al. (Tue,) studied this question.