Reduction of the Beam Hardening Artifacts in the X-Ray Computer Tomography: Energy Discrimination with a Photon-Counting Detector

Yukino Imura, Takuto Yanagida, Hisashi Morii, Hidenori Mimura, Toru Aoki

Graduate School of Science and Technology, Shizuoka University, Hamamatsu, Japan.
Research institute of Electronics, Shizuoka University, Hamamatsu, Japan.

DOI: 10.4236/wjnst.2012.24026                

Abstract

The material identification is a pressing requirement for the sensitive security applications. Dual-energy X-ray computer tomography (DXCT) has been investigated for material identification in the medical and security fields. It requires two tomographic images at sufficiently different energies. To discriminate dangerous materials of light elements such as plastic bombs in luggage, it is needed to measure accurately with several tens of kilo electron volts where such materials exhibit significant spectral differences. However, CT images in that energy region often include artifacts from beam hardening. To reduce these artifacts, a novel reconstruction method has been investigated. It is an extension of the Al-gebraic Reconstruction Technique and Total Variation (ART-TV) method that reduces the artifacts in a lower-energy CT image by referencing it to an image obtained at higher energy. The CT image of a titanium sample was recon-structed using this method in order to demonstrate the artifact reduction capability.

Keywords

X-Ray Computer Tomography; Artifacts; Photon Counting; Iterative Reconstruction; ART-TV; Titanium Sample; Security Applications

Conflicts of Interest

The authors declare no conflicts of interest.

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