High-Resolution Dual-Energy X-ray Imaging Enabled by Transparent Thermally Activated Delayed Fluorescence (TADF) Scintillation Screen

Abstract

Dual-energy X-ray imaging technology provides more detailed material-specific information by using a second X-ray spectrum. However, conventional dual-energy X-ray imaging typically necessitates two separate exposures to combine high- and low-energy projections. This process can result in image misalignment and increased radiation doses. Herein, a dual-energy X-ray imaging system using a two-layered scintillator was developed, featuring transparent pure organic thermally activated delayed fluorescence (TADF) materials as the low-energy absorption layer and LYSO as the high-energy absorption layer. Separating the energy bins on the detector side enables the simultaneous and sequential acquisition of low- and high-energy projections with a single X-ray exposure. This two-layered scintillator achieves a high imaging resolution of 23 lp/mm, surpassing most conventional single-layer scintillators. Additionally, the effectiveness of this dual-energy imaging system was demonstrated in a toolbox inspection, where complex objects inside were successfully imaged and differentiated, capturing all intricate details in a single X-ray exposure.