Simple Quasi-Exact Filtered Backprojection Algorithms for Long-Object Problem in Helical Cone-Beam Tomography
نویسندگان
چکیده
Since the development of multi-slice helical CT, cone-beam reconstruction with a helical vertex path is receiving increasing attention. The current multi-slice CT scanners are adopting a class of approximate reconstruction algorithms which can be viewed an extension of the 2-D FBP algorithm. However, these approximate algorithms break down as the pitch of helix becomes large. In fact, major companies are beginning to develop a large area detector having more than 100 detector rows which allows a helical scan with a quite large pitch. This limitation of approximate algorithms motivated researchers to develop a class of exact reconstruction algorithms [1]-[6].
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