论文部分内容阅读
X线摄影能量范围内,主要作用形式是光电效应和康普顿效应。康普顿效应随X线能量的增加而增加。 光电效应作用特点为射线对比度高,影像层次低。康普顿效应则使射线对比度下降。影像层次增高。根据其特点,X线摄影中产生高对比度的管电压为40-60 kVp,称为低电压。产生高影像层次的管电压为100 kVp以上,称为高电压。 高、低管电压摄影,在反映胶片对比度及影像层次上有着根本的不同。投照中应根据X线的作用特点和诊断需求,正确选
Within the scope of X-ray photography, the main mode of action is the photoelectric effect and the Compton effect. Compton effect increases with increasing X-ray energy. The photoelectric effect is characterized by high contrast, low image level. Compton effect makes the ray contrast decreased. Image level increased. According to its characteristics, X-ray photography to produce high contrast tube voltage of 40-60 kVp, known as the low voltage. The tube voltage that produces a high-image level is above 100 kVp, which is called high voltage. High, low voltage photography, in the film contrast and video level has a fundamental difference. Projection should be based on the role of X-ray features and diagnostic needs, the correct election