Development and evaluation of a selenium-based flat-panel digital x-ray detector system based on quality factor

Abstract

G Nowadays, large area, flat panel solid state detectors are being investigated for digital radiography. In this paper, development and evaluation of a selenium-based flat-panel digital x-ray detector are described. The prototype detector has a pixel pitch of 139 ໃ and a total active imaging area of 7 inch × 8.5 inch, giving a total of 1.9 million pixel.This detector include a x-ray imaging layer of amorphous selenium as a photoconductor which is evaporated in vacuum state on a TFT flat panel, to make signals in proportion to incident x-ray. The film thickness was about 500 ໃ . To evaluate the imaging performance of the digital radiography(DR) system developed in our group, sensitivity, linearity of the response of exposure, the modulation transfer function(MTF) and detective quantum efficiency(DQE) of detector was measured. The measured sensitivity was 4.16×10 6 ehp/pixel mR at the bias field of 10 V/ໃ : The beam condition was 41.9 KeV. Measured MTF at 2.5 lp/mm was 52%, and the DQE at 1.5 lp/mm was 75%. And the excellent linearity was showed where the coefficient of determination (r 2 ) is 0.9693.

An Improved Design of Flat Panel Detector with Phototransistor PH101 Analysis of The Tube Voltage Setting

“…To be able to produce radiographs that provide as much information as possible, optimal radiographs are needed [7]. Radiographic quality includes density, contrast, sharpness and distortion, it is necessary to make efforts to suppress factors that can reduce radiographic quality [8] [9]. The greater the kV, mA, the time given can reduce the contrast, quantity, and brightness of the radiographic image [10].…”