为了解射线检测标准中最高电压限值曲线所对应的技术细节, 对现行及最新制订的射线检测标准中的相关内容进行了分析比较, 追溯了最高电压限值规定的由来以及其发展变化。在此基础上, 定量分析了最高电压限值与透照厚度间的函数关系, 初步探讨了最高电压限值与图像对比度间的内在关联。分析表明, 射线检测标准中规定的最高电压限值曲线, 是按指数函数关系进行设置的; 最高电压限值曲线在胶片照相检测中应用较好, 但在射线数字成像检测中并不适用; 如果对射线检测中的主因对比度、图像信噪比进行综合分析, 则有望规定出射线数字成像检测用的最高电压限值。

To investigate the details related with the defined maximum values of tube voltage in some radiographic testing standards, the very contents in present effective standards and new developing standards were compared and analyzed, and then the origin and changes of this specification were traced. Thus, relationship between maximum values of tube voltage and penetrated thickness was quantitatively analyzed, and correlation between maximum values of tube voltage and contrast of testing result was quantitatively calculated roughly. From the analysis, we know the curve of maximum X-ray voltage versus penetrated thickness is made according to certain math function. Maximum values on the curve are the best practice values for film radiography, however, these values are not quite applicable for digital radiographic testing. If comprehensive analysis on essential contrast and signal-to-noise in radiographic testing was carried out, maximum X-ray voltage applicable for digital radiographic testing would be prescribed.