W. Huang et al., An asynchronous, pipelined, electronic acquisition system for Active Matrix Flat-Panel Imagers (AMFPIs), NUCL INST A, 431(1-2), 1999, pp. 273-284
The development of a full-custom electronic acquisition system designed for
readout of large-area active matrix hat-panel imaging arrays is reported.
The arrays, which comprise two-dimensional matrices of pixels utilizing amo
rphous silicon thin-him transistors, are themselves under development for a
wide variety of X-ray imaging applications. The acquisition system was spe
cifically designed to facilitate detailed, quantitative investigations of t
he properties of these novel imaging arrays and contains significant enhanc
ements compared to a previously developed acquisition system. These enhance
ments include pipelined preamplifier circuits to allow faster readout speed
, expanded addressing capabilities allowing a maximum of 4096 array data li
nes, and on-board summing of image frames. The values of many acquisition s
ystem parameters, including timings and voltages, may be specified and down
loaded from a host computer. Once acquisition is enabled, the system operat
es asynchronously of its host computer. The system allows image capture in
both radiographic mode (corresponding to the capture of individual X-ray im
ages), and fluoroscopic mode (corresponding to the capture of a continual s
eries of X-ray images). A detailed description of the system architecture a
nd the underlying motivations for the design is reported in this paper. (C)
1999 Published by Elsevier Science B.V. All rights reserved.