无损检测 工业X射线系统中焦斑的特性 第2部分:带孔或圆盘型测试对象的边缘法

[中文适用范围]： 本文件规定了通过边缘法测量有效焦斑尺寸 >0.2 μm 的 X 射线系统的方法，该方法应用于从孔型或盘型测试对象获取的数字图像（如果未观察到相位对比）。X 射线图像的成像质量和分辨率在很大程度上取决于有效焦斑的特性，特别是其尺寸和从探测器平面观察到的二维强度分布。 本文件规定了在根据 ISO 32543-1 的针孔法不适用的情况下，为工业 X 射线管的标准、微米和微焦点确定有效尺寸（维度）的程序。本文件中规定的方法适用于在没有针孔相机的情况下测量和长期监测焦斑尺寸。 如果使用根据 6.2.1 制造的具有较低公差的特殊孔测试对象（见图 1），制造商可以使用本文件。对于有效焦斑尺寸的测量，由于制造公差为 ±10%，本文件方法的准确性低于 ISO 32543-1（针孔法）和 ISO 32543-3（微焦点管）中规定的方法，如果使用 ASTM 孔板图像质量指示器（参见 ASTM E1025、ASTM E1742）。 注：对于商业 X 射线管类型的表征（即用于广告或贸易），附录 A 中的标称值是首选。 [外文原描述]： This document specifies a method for the measurement of effective focal spot dimensions > 0,2 µm of X-ray systems by means of the edge method applied to digital images taken from hole type or disk type test objects if no phase contrast is observed. The imaging quality and the resolution of X-ray images depends highly on the characteristics of the effective focal spot, in particular its size and two-dimensional intensity distribution as seen from the detector plane. This document specifies procedures for determining the effective size (dimensions) of standard, mini and micro focal spots of industrial X-ray tubes for users in applications where the pin hole method according to ISO 32543-1 is not applicable. The method specified in this document is applicable for measurement and long-term monitoring of focal spot sizes without a pin hole camera. This document can be used by manufacturers, if special hole test objects manufactured with lower tolerances according to 6.2.1 are applied (see Figure 1 ). For measurements of the effective focal spot size, the accuracy of the method in this document is lower than the methods specified in ISO 32543-1 (pin hole method) and ISO 32543-3 (microfocus tubes) if using ASTM hole plate IQIs (see ASTM E1025, ASTM E1742), due to its manufacturing tolerance of ±10 %. NOTE For characterization of commercial X-ray tube types (i.e. for advertising or trade), the nominal val ues of Annex A a re preferred.