THIN-FILM, FLAT PANEL, PIXELATED DETECTOR ARRAY FOR REAL-TIME DIGITAL IMAGING AND DOSIMETRY OF IONIZING RADIATION

摘要

A thin-film, flat panel, pixelated detector array servingas a real-time digital imager and dosimeter for diagnostic ormegavoltage X rays or gamma rays, including a plurality ofphotodiodes made of hydrogenated amorphous silicon arrayed incolumns and rows upon a glass substrate. Each photodiode isconnected to a thin film field effect transistor also locatedupon the glass or quartz substrate. Upper and lower metalcontacts are located below and above the photodiodes toprovide the photodiodes with a reverse bias. The capacitanceof each photodiode when multiplied by the resistance of thefield effect transistor to which it is connected yields an RCtime constant sufficiently small to allow fluoroscopic orradiographic imaging in real time.