; Cen Yu-Wan
; Yu Xiao-Liu] Anhui Univ Technol, Sch Mech Engn, Maanshan 243002, Peoples R China
; [Zhu Pei-Ping] Chinese Acad Sci, Inst High Energy Phys, Beijing Synchrotron Radiat Facil, Beijing 100049, Peoples R China
; [Hu Xiao-Fang] Univ Sci & Technol China, CAS Key Lab Mech Behav & Design Mat, Hefei 230026, Peoples R China
Based on the 360 degrees computing method of refractive angle for parallel beam diffraction enhanced imaging computed tomography (DE-CT) technique, a new algorithm used to calculate the refractive angle for fan-beam DE-CT technique is developed. The refractive index gradient can be obtained by using the new algorithm with projection data of an object in the range of 0-360 degrees, and the new algorithm only needs to set the analyser at half slope position of the rocking curve.