Influence of metal screens on contrast in megavoltage x-ray imaging.
Influence of metal screens on contrast in megavoltage x-ray imaging.
复制标题
金属屏对兆伏 X 射线成像对比度的影响。
DOI：
10.1118/1.594610
复制
发表时间：
1979
期刊：
影响因子：
3.8
通讯作者：
B. Bjärngard
中科院分区：
文献类型：
--
作者：
R. T. Droege;B. Bjärngard
为了确定将这些探测器应用于巨型X射线成像的这些检测器的对比度，研究了金属屏幕膜检测器的射线照相对比度。膜对比伽玛被发现与金属屏幕组成无关。接触几何形状中散射膜剂量比的测量表明，要么的1.5 g/cm2铜的厚前屏幕为2.5 g/cm2铅可为所研究的光子能提供最佳对比度（60CO和4-MV X射线）。还发现相同的厚度适用于气隙几何形状，与接触几何相比，这显着改善了对比度。发现后导线屏幕没有提供对比度的改进。
The radiographic contrast of metal screen-film detectors was investigated in order to determine the contrast capabilities of these detectors applied to megavoltage x-ray imaging. The film contrast gamma was found to be independent of the metal screen composition. Measurement of the scatter-to-primary film dose ratio in contact geometry demonstrated that a thick front screen of either 1.5 g/cm2 copper of 2.5 g/cm2 lead provides optimum contrast for the photon energies studied (60Co and 4- and 8-MV x rays). The same thickness were also found to be suitable in an air gap geometry which significantly improved the contrast compared to the contact geometry. Rear lead screens were found to provide no contrast improvement.