Speaker
Description
Dual-energy X-ray imaging utilizing a dual-layer flat panel detector (DE-FPD) is widely used in radiography and computed tomography. A conventional DE-FPD is composed of a top layer featuring a 200 μm-thick cesium iodide scintillator and a bottom layer with a 600 μm-thick scintillator, both connected to an identical amorphous silicon thin-film transistor array. These layers are separated by a 1 mm-thick copper (Cu) filter, which enhances spectral separation to improve dual-energy images. However, the Cu filter reduces the number of entrance photons reaching the bottom layer, significantly diminishing the quality of selective dual-energy images. This study introduces a filter-free DE-FPD design, incorporating a thicker (500 μm-thick) top layer scintillator, and evaluates the detector's performance using Geant4 Monte Carlo simulation. The performance was assessed by measuring the modulation transfer function, noise power spectrum, and noise-equivalent quanta for both the top and bottom layers under RQA5 and RQA7 X-ray beam quality. Our preliminary findings suggest that the proposed DE-FPD exhibits improved detector performance compared to the conventional model. More systematic and quantitative simulation results will be presented in the paper.