<title>Progress report on the performance of real-time selenium flat-panel detectors for direct x-ray imaging</title>

Abstract

Real time flat panel detectors based on amorphous selenium (a-Se) have demonstrated to be the most advanced technology for direct conversion X-ray imaging in various medical applications. In continuation of real time detector development, ANRAD Corporation introduce in this paper a large size 14 inches X 14 inches active area detector built with an amorphous selenium (a-Se) converter coated on a TFT array. This new detector is a scaled up version of the 9 inches X 9 inches presented last year based on a TFT array with 150 um x 150 um pixel and a 1000 mm thick a-Se PIN structure operated at 10V/um. DQE(f=0) measurements were performed in low dose range and demonstrated to be in agreement with a linear model including 2500e of electronic noise. It is also shown that the spatial resolution (MTF) could be controlled by selenium coating process and can almost reach the theoretical limit defined by the pixel pitch. Finally, the first 14 inches X 14 inches chest image is presented.