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 serving as a real-time digital imager and dosimeter for diagnostic or megavoltage X rays or gamma rays, including a plurality of photodiodes (30) made of hydrogenated amorphous silicon arrayed in columns and rows upon a glass substrate (12). Each photodiode (30) is connected to a thin film field effect transistor (52) also located upon the glass or quartz substrate (12). Upper and lower metal contacts (38, 22) are located below and above the photodiodes (30) to provide the photodiodes (30) with a reverse bias. The capacitance of each photodiode (30) when multiplied by the resistance of the field effect transistor (52) to which it is connected yields an RC time constant sufficiently small to allow fluoroscopic or radiographic imaging in real time.