FLIGHT DIGITAL EDUCATION PIXELMATRIC DETECTOR AND DOSIMETRY OF IONIZING RADIATION IN EXCEPT TIME

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 made of hydrogenated amorphous silicon arrayed in columns and rows upon a glass substrate. Each photodiode is connected to a thin film field effect transistor also located upon the glass or quartz substrate. Upper and lower metal contacts are located below and above the photodiodes to provide the photodiodes with a reverse bias. The capacitance of each photodiode when multiplied by the resistance of the field effect transistor to which it is connected yields an RC time constant, tau RC, sufficiently small to allow fluoroscopic or radiographic imaging in real time. Specifically, IMAGE where P=the pixel-pixel pitch in mu m, where DIFFERENCE 25/=p/= DIFFERENCE 10,000, L=the length, in cm, of one column of pixels sensors of the array, where DIFFERENCE 2/=L/= DIFFERENCE 60, IFPS=instantaneous frame rate per second which is the effective rate at which the array is being readout, where DIFFERENCE 1/=IFPS/= DIFFERENCE 500, and SN=the inverse of the degree to which each pixel sensor needs to be sampled and thus recharged, where DIFFERENCE 10/=SN/= DIFFERENCE 10,000.