Nondestructive reverse engineering of trace maps in multilayered PCBs

The focus of this paper is on separating the layers of an unpopulated, two layered circuit card assemblies/printed circuit boards (CCA/PCB) using X-ray stereo imaging. By separating the layers, we mean that our desire is to separate the traces on each layer of any multi-layered CCA. The final end product is envisioned to be an interactive, automated trace reconstruction system which will separate individual trace layers on a multi-layered PCB. Some of the benefits of such a system are: (1) eliminates the need to have prior knowledge of the CCA via examination of its engineering data; (2) the system can be generalized to different types of CCA's which have different number of trace layers, without any modification to the software; (3) allow the examination of each trace layer of a (multi-layered) CCA separately; (4) a non-intrusive technique which would not subject the CCA to any electronic stimulation.