title: A modified discrete algebraic reconstruction technique for multiple grey image reconstruction for limited angle range tomography.
abstract: The `missing wedge', which is due to a restricted rotation range, is a major challenge for quantitative analysis of an object using tomography. With prior knowledge of the grey levels, the discrete algebraic reconstruction technique (DART) is able to reconstruct objects accurately with projections in a limited angle range. However, the quality of the reconstructions declines as the number of grey levels increases. In this paper, a modified DART (MDART) was proposed, in which each independent region of homogeneous material was chosen as a research object, instead of the grey values. The grey values of each discrete region were estimated according to the solution of the linear projection equations. The iterative process of boundary pixels updating and correcting the grey values of each region was executed alternately. Simulation experiments of binary phantoms as well as multiple grey phantoms show that MDART is capable of achieving high-quality reconstructions with projections in a limited angle range. The interesting advancement of MDART is that neither prior knowledge of the grey values nor the number of grey levels is necessary.
authors.affiliation: National Synchrotion Radiation Laboratory, University of Science and Technology of China, 3#419, No.42 Hezuohua South Road, Hefei, Anhui 230029, People's Republic of China.
authors.forename: Zhiting
authors.initials: Z
authors.lastname: Liang
authors.affiliation: National Synchrotion Radiation Laboratory, University of Science and Technology of China, 3#419, No.42 Hezuohua South Road, Hefei, Anhui 230029, People's Republic of China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Guan
authors.affiliation: National Synchrotion Radiation Laboratory, University of Science and Technology of China, 3#419, No.42 Hezuohua South Road, Hefei, Anhui 230029, People's Republic of China.
authors.forename: Gang
authors.initials: G
authors.lastname: Liu
authors.affiliation: National Synchrotion Radiation Laboratory, University of Science and Technology of China, 3#419, No.42 Hezuohua South Road, Hefei, Anhui 230029, People's Republic of China.
authors.forename: Xiangyu
authors.initials: X
authors.lastname: Chen
authors.affiliation: National Synchrotion Radiation Laboratory, University of Science and Technology of China, 3#419, No.42 Hezuohua South Road, Hefei, Anhui 230029, People's Republic of China.
authors.forename: Fahu
authors.initials: F
authors.lastname: Li
authors.affiliation: National Synchrotion Radiation Laboratory, University of Science and Technology of China, 3#419, No.42 Hezuohua South Road, Hefei, Anhui 230029, People's Republic of China.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Guo
authors.affiliation: National Synchrotion Radiation Laboratory, University of Science and Technology of China, 3#419, No.42 Hezuohua South Road, Hefei, Anhui 230029, People's Republic of China.
authors.forename: Yangchao
authors.initials: Y
authors.lastname: Tian
keywords: image reconstruction; limited-angle range; modified discrete algebraic reconstruction technique (MDART); multiple grey image