Abstract: A flat panel x-ray imager exhibiting reduced ghosting effects and overvoltage protection by appropriate leakage current characteristics of the thin-film transistor array. A top electrode of a suitable material is directly on an amorphous selenium-based charge generator layer allowing charge transport across the layer, thereby reducing ghosting. Alternatively, a non-insulating organic layer may be between the top electrode and the charge generating layer. The thin-film transistors have leakage current that rises relatively slowly with voltage across the transistor within a range that matches exposure through an object being imaged but rises at a sufficiently higher rate within a higher range to provide protection even when a corresponding region of the charge generator layer receives greater amounts of x-rays. A voltage is applied to the top electrode. This voltage may be within the range of 500 V to 2,000 V.

Abstract: A method for developing a set of gain correction coefficients corrected for structural noise to be used in correcting the digital values representing an image captured by a pixelated detector having a plurality of individual sensors. The gain correction coefficients are developed by first obtaining a first set gain correction coefficients using a flat exposure and adjusting the individual sensor gain output so that all sensors produce the same output value, and then applying a smoothing filter to the first set of gain correction coefficients to obtain a new set of corrected gain correction coefficients.