Improved imaging for X-ray inspection systems

A number of advancements for X-ray inspection systems have recently been implemented in the image presented to the operator. Advances in the use of color and image fusion techniques have been developed to maximize the information available in the initial view shown on the monitor. Different techniques are appropriate depending upon the size of the inspection item. Inspection of checked and carry-on baggage requires imaging methods that would not be appropriate for use on larger, more complex objects such as cargo containers or whole trucks. Color-coded presentation of CT images of baggage imposes yet other demands. Comparative images and analyses are presented to support choices for imaging on L-3 Communications systems in terms of the conflicting requirements of cost, sensitivity, resolution, and penetration. A number of enhancements are available to the operator and their influence on system performance is explored. Some experimental enhancements are demonstrated and their trade-offs discussed. The imaging system is ultimately based on hardware, and the choice of detectors, amplifiers, and sampling methods plays an important role in overall performance. Image degradation can be caused by deficiencies in the imaging hardware. Effects such as detector cross-talk and afterglow will negatively impact system performance. Recognition of these factors and steps to mitigate them are discussed. The effect of X-ray source choices such as beam voltage, milliamps, and sampling rate has a direct influence on the image quality and bag dose. Results of theoretical modeling as well as results on actual systems are presented. For a given bag dose, the trade-off between sensitivity, resolution, and penetration are considered. Possibilities for future advancements in imaging for X-ray inspection systems are explored.