Andy Foster, X-Tek's Senior Engineer, commented that, contrary to popular belief, silicon chips are not susceptible to damage from x-rays as long as they are not powered up when examined. X-ray bombardment of powered chips can cause damaging free electrons to be thrown off into the silicon. Silicon chips can in fact withstand very high doses of x-rays without harm, but as Foster pointed out, X-Tek systems only deliver minute doses anyway.
X-Tek systems are controlled by industrial rackmount PCs, with standard PCI motherboards, running exclusively on Windows NT. The modular nature of X-Tek's own iXS control software means that the Matrox Imaging Library (MIL), a comprehensive development toolbox for image capture and processing applications, is ideally suited to the X-Tek approach. Image processing is therefore kept separate from the manipulator and x-ray control modules. Foster commented: &quuot; went for a development library rather than an off-the-shelf program, because we needed to bring all the different functionalities together into one package, but still be able to develop them separately ourselves."
Although X-Tek systems currently uses Matrox Pulsar frame grabber boards for image capture, the company is planning a two-tier approach, utilising Matrox Meteor-IIs for lower-end applications. This will make budget systems as cost-effective as possible, while Matrox Corona boards will be used for more costly, higher-end applications. Uniquely, in these days of outsourcing and JIT manufacturing, the image intensifier, camera and high-voltage generator are the only other bought in components in an X-Tek system. The x-ray gun is a specialised micro-focus unit that gives much higher resolution than those found in the crowded security x-ray market.
X-ray emissions are random by nature, which means they create 'speckled' images for capture by the frame grabbing board in the PC, so the first processing task is to clean up each image, which is done by acquiring several frames and averaging their contents. Front-end software has been written by X-Tek to create an image capture and processing application, utilising the Matrox Imaging Library so that brightness, contrast and gamma can be adjusted, while pseudo-3D filters can also be applied to give artificial depth to the view. These filters are based on standard Matrox filters for edge enhancement and sharpening, amongst others. Each captured view can then be labelled for easy identification prior to saving.
The digital components of PimaxScan include a Uniqvision UP930 Camera Link camera, a Matrox Helios XCL frame grabber, and an embedded PC fitted with an Intel 915-based motherboard and an Intel Pentium 4 processor. The system runs Windows XP Embedded. All the software was designed in C++ and built with the Matrox Imaging Library (MIL). Not only does the software control image acquisition, display and archiving, but the image processing as well. "MIL provides all the algorithms and functions for processing. In particular we used the Edge Finder module for border detection, as well as Low-pass filters, recursive filters, rotations, and digital subtraction," explains Sentoni. "We also used some LUTs to enhance the images for display on dual-screen terminals."