In order to design the full system of dual-energy X-ray scanner, each component of the system has been fabricated and tested. The high-energy X-ray detector modules used a ceramic scintillator of Eu3+-doped (Gd,Y)(2)O-3, manufactured using Glycine Nitrate Process (GNP). This was coupled to a 16-channel linear array PIN-type photodiode. The low-energy module was a commercially available Lanex Regular screen that was also coupled to a 16-channel linear array PIN-type photodiode. The 16-channel linear array PIN-type photodiode of 1.5 mm x 3.2 mm was fabricated in the process of Electronics and Telecommunications Research Institute (ETRI). With a data acquisition system, signal-to-noise ratio was measured at low X-ray energy and low photon flux to evaluate each scintillator-coupled detector module. Through the experiment results and analysis, we inspected each component of the system as a dual-energy single-exposure X-ray scanner. (C) 2007 Elsevier B.V. All rights reserved.