Performance evaluation of dual-energy X-ray screening system

The increasing demand for improved detection capabilities in X-ray security screening systems has led to the development of an advanced transmission X-ray scanner featuring a variable tube voltage and a dual-energy detector. In this study, the imaging performance of the developed scanner was experimentally evaluated, and the results were compared with those obtained from a Geant4-based Monte Carlo (MC) simulation model for validation. Performance assessment was conducted in accordance with standardized protocols using the ASTM F792-HP test kit. Wire display capability (Test 1) was analyzed quantitatively using a one-tailed t-test with Bonferroni correction to enable objective and reproducible verification of wire detectability. The scanner successfully detected wires down to 34 AWG, surpassing the domestic regulatory requirement of 30 AWG. Spatial resolution performance (Test 3) was evaluated using bar pattern phantoms and further refined through simulation with high-resolution virtual phantoms. This determined the resolution limit of the scanner to be 0.8 mm. The close agreement between the experimental measurements and the simulation results confirmed the predictive accuracy of the validated MC model. These results demonstrate that the developed scanner exceeds the performance criteria required for security screening applications and that the validated simulation framework is an effective tool for optimizing systems and achieving regulatory certification.