摘要
本文主要基于Radon正反变换,建模研究CT系统参数标定以及成像原理。针对问题1,以正方形模板的中心点为直角坐标系的原点,水平方向为X轴,竖直方向为Y轴,运用几何方法、数据分析、图像拟合等方法,解出CT系统探测器单元之间的距离为0.2768mm,其旋转中心的坐标为(-9.2734,5.9516)。CT系统的初始角度为33.0363°,终止角度为208.4130°,总共转过175.3767°。针对问题二和三,以问题一中得到的角度信息作为Radon反变换的参数,绘制附件2的CT系统成像图。主要使用三次样条插值与像素坐标转化直角坐标等方法,解出成像图的吸收率和几何图的吸收率之间的关系为:μ1=2μ2,转换得出几何图中各点吸收率值。
We built a model to study the parameter calibration and the image-forming principle of CT system based on Radon transform in two directions, i.e., the positive direction and the negative direction. For question1, according to the image information of measured object gotten from CT system units, we got the following results: 1.The distance between CT system units is 0.2768 mm, 2.The coordinates of the rotation center is(-9.2734, 5.9516) and 3.the 180 rotation directions of the CT system, the initial angle is 33.0363°, the end angel is 208.4130°, totally rotated 175.3767°. For the question 2 and question 3, we use the angel information gotten in question 1 as the parameter of Radon transform, to draw the image-forming picture of CT system,and the relationship between two pictures:μ_1=2μ_2. We built an absorptivity matrix and finally by using the relationship between image-forming picture and geometric picture, we can get the ten absorptivity as show in affix 4 and affix 5.
出处
《数码设计》
2018年第1期27-31,共5页
Peak Data Science
基金
国家自然科学基金(61305052)
赣南师范大学校级教改课题(150656)
