针对薄层结构物质的微焦点摆动式分层成像方法研究

Study of multi-plane microfocus swing laminography for the flat components

对薄层结构的复合材料及多层电路板进行密度分布情况及分层成像的研究 ,是无损检测技术的一个重要应用领域。提出了一种新的成像方法 ,在现有微焦点 X辐射成像系统的基础上 ,采用一种特殊的摆动式扫描方式 ,基于非线性的重建成像算法 ,具有扫描速度快、算法简单、实时性高等特点 。

The inspection of flat components like soldered joints with complex structures is a very important application of non destructive test and requires high sophisticated nondestructive testing methods. Based on the microfocus X ray radiation imaging system, a new reconstruction method will be put forward in this project. These objects can be analyzed with computed laminography (CL) which requires a simple swing of the object to be inspected through the fan beam of a X ray source. The object is irradiated by the X rays under different angles. Image processing can be applied in combination with the multi plane reconstruction for resolution and contrast enhancement. Linear reconstruction algorithm is based on the filtered or unfiltered back projection or averaging method respectively. Non linear reconstruction can be derived from methods for object tracing. We applied extreme value methods and developed a correlation method.