New solid-state x-ray imagers known as digital flat-panel x-ray detectors are about to be launched in the field of medical diagnostics. The combination of active-matrix technologies developed for active-matrix liquid-crystal displays and x-ray detection materials constitutes the basis of the detectors. Recently, two kinds of direct-conversion detectors have been developed in order to improve their performance. One is a detector using a thick x-ray photoconductor (∼1 mm) made of amorphous selenium, and the other is a novel hybrid panel detector using an x-ray photoconductor made of polycrystalline Cd(Zn)Te. As a result, excellent resolution and good linear sensitivity have been achieved. These detectors have great promise as next-generation digital imaging systems for fluoroscopy and radiography.
