While traditional silver halide film and chemical systems had long been the only option for radiographers, today's NDE technicians have a choice of filmless digital systems that can offer a number of potential advantages and savings. Among these choices is Computed Radiography (CR), a state-of-the-art, yet simple to use, technology utilizing photostimulable phosphors on a flexible support. These Imaging Plates (IPs) are capable of storing radiographic latent images that, upon subsequent irradiation with a red laser, are extracted, reconstructed, and exploited in the digital workspace.

This paper will review the history, basic technology, and principles of operation of Computed Radiography and flexible storage phosphor plates. Where applicable, analogies to more familiar film systems will be made to facilitate a clear understanding of system performance and related variables. A system workflow will be described, and performance characteristics and advantages over film systems will show why CR and phosphor plate technology is becoming a leading choice in applications such as the harsh NDE erosion/corrosion environment. Finally, a brief glimpse into the future will hint at how further evolution can take radiographic NDT to new levels of productivity.

KEYWORDS: flexible storage phosphor plates, computed radiography, photostimulable luminescence, bariumfluorobromide, europium