基于一种新型扫描模式的不完全数据CT重建

摘要

扫描模式是直接决定图像重建实现方案的重要因素之一.随着CT技术的不断发展,扫描模式也在不断地更新换代.以降低剂量、工程条件受限为应用背景的不完全数据图像重建和扫描模式有着更加密切的联系.立足于不完全数据的图像重建,定制了一种直线轨迹的扫描模式,并在这种扫描模式下,探讨半区域、外部区域、内部区域的不完全数据的精确重建.数值上,以该扫描模式为基础,对Shepp-Logan产生的投影数据进行重建,实现了对目标图像的精确求解,初步证明了方案的可行性.%Scanning mode is the key factor which derectly affects image reconstruction. With the development of CT technology, scanning mode is changing continuously. Incomplete data image reconstruction with application background of radiation dose reduction and limited constructional conditions is related closely with scanning mode even more. It introduces a line - style scanning mode for incomplete data image reconstruction. Following the utilization of this scanning mode, half- region problem, outside problem and inside problem are discussed respectively. Numerically, object is exactly reconstructed from the projection data produced from Shepp - Logan model based on this scanning mode. And the feasibility of this scanning mode is proved preliminarily.