Figure 1. (a) CT image of the upper zone of a chest phantom and four polymer tubes filled with water placed on the chest wall. The images of polymer tubes I, II, III and IV were used as target objects to evaluate streak artefacts. (b) Magnified image of polymer tube I, which was reconstructed by the FC01 reconstruction kernel. (c) Magnified image of polymer tube I, which was reconstructed by the FC50 reconstruction kernel. (d) Magnified image of polymer tube I, as reconstructed by the FC52 reconstruction kernel. Streak artefacts increased in order of FC01<FC50<FC52.