<title>High-resolution digital radiography and three-dimensional computed tomography</title>

Abstract

The predominant method used for radiographic inspection of aerospace hardware is film radiography, which is costly and time consuming. Each inspection requires many films to obtain successful viewing geometries under various x-ray conditions. Film radiography is also labor intensive, since the operator must place the film, expose it, remove it, and develop it before the images can be viewed or interpreted. In complex film inspections, it may not be possible to optimize the inspection because of the short periods allotted for nondestructive inspection (NDI). Storage and retrieval of the x-ray film is also rather cumbersome and labor intensive. Finally, film radiographs must be digitized and processed to extract quantitative information. Real-time radiographic (RTR) and near-real-time radiographic imaging systems offer solutions to some of the problems of film radiography. First, the operator can view the image immediately upon acquisition and thus optimize the inspection in a timely manner, and second, because the images are acquired electronically, the need for developing images is eliminated, and image analysis, storage, and retrieval are simplified. In this paper, the authors describe new solid-state x-ray camera system designs, the new scintillating glass and fiber-optic x-ray-to-light conversion screens, and their performance in x-ray tests. They compare themore » performance of these systems with that of x-ray image-intensifier tube systems and discuss the use of these new systems for acquisition of 3-D CT images.« less