Feasibility study of applying X-ray tomographic imaging with a straight-line trajectory scan to security inspection

X-ray tomographic imaging with a straight-line trajectory scan, which has advantages of high speed, no overlapping and relatively low cost, can be a good supplemental configuration for current X-ray imaging security inspection systems. With detector no relative rotation or translation, the straight-line trajectory tomographic imaging (SLTTI) has the capability of fast examining objects online. A key challenge of SLTTI is that its image reconstruction suffers from an insufficient data (limited angle) problem. To fully investigate the feasibility of application to security inspection, we are developing such an experimental imaging system. In this paper, the key considerations of the system design and optimization were presented firstly; then an total variation (TV) based Gerchberg-Papoulis (GP) type extrapolation was introduced as the image reconstruction strategy to overcome the limited-angle problem; and finally some preliminary experimental results were given, through which our theories and methods were validated to be effective.