Improved imaging performance of a 14x17-inch Direct Radiography™ System using Se/TFT detector

被引：69

作者：

Lee, DL ^{[1
]}

Cheung, LK ^{[1
]}

Rodricks, B ^{[1
]}

Powell, GF ^{[1
]}

机构：

[1] Sterling Diagnost Imaging Inc, Direct Radiog Corp, Newark, DE USA

来源：

PHYSICS OF MEDICAL IMAGING | 1998年 / 3336卷

关键词：

digital radiography; selenium; direct conversion; X-rays; thin-film-transistor array; medical imaging; amorphous silicon; flat-panel imager;

D O I：

10.1117/12.317017

中图分类号：

R318 [生物医学工程];

学科分类号：

0831 ;

摘要：

Progress is discussed on the improvement of a Direct Radiography(TM) solid state, flat panel, digital detector designed for use in general radiographic applications. This detector, now known as DirectRay(TM), operates on the principle of direct detection of X-ray photons with a selenium photoconductor and consists of 500 mu m thick amorphous selenium coupled to an amorphous silicon thin-film-transistor (TFT) readout array. This device is fabricated with a 14 x 17-inch (35 x 43-cm) active imaging area, corresponding to 2560 x 3072 pixels having dimensions of 139 mu m x 139 mu m and a geometrical fill factor of 86%. Improvements include a TFT array design upgrade with reduced noise characteristic, lower-noise readout electronics, and improved interfaces. Clinical radiographic images are currently being generated with the DirectRay detector using an X-ray exposure level equivalent to that of a 400 speed screen-film combination while maintaining the superior spatial resolution that is inherent in the direct conversion method. An effective sensor restoration technique has been implemented that eliminates the potential for selenium memory artifacts after a high dose. New results on NPS, MTF, DQE and signal linearity are presented. Detectability of low contrast objects using FAXiL test objects as well as the results of clinical studies are discussed.

引用

页码：14 / 23

页数：10