Abstract: Systems and methods for improving radiographic scanning. In an example, the technology relates to a system for performing radiographic scanning. The system includes a photon source configured to emit photons. The system also includes a photon counting detector for detecting photons emitted from the photon source after passing through a target. The photon counting detector comprising first pixels having a first size and second pixels having a second size, and the first size is greater than the second size.

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 photodetector for X-ray applications includes a photodiode at each pixel location that is gated to reduce leakage of charge from the photodiode. A gate layer may be disposed around the entire peripheral edge of the detector, and maintained at a common potential with a contact layer, or at a different potential. A passivation or dielectric layer separates the gate layer from the photodiode. Leakage around the edge of the diode that can result from extended exposure to radiation is reduced by the gate layer.

Abstract: A photodetector for X-ray applications includes a photodiode at each pixel location that is gated to reduce leakage of charge from the photodiode. A gate layer may be disposed around the entire peripheral edge of the detector, and maintained at a common potential with a contact layer, or at a different potential. A passivation or dielectric layer separates the gate layer from the photodiode. Leakage around the edge of the diode that can result from extended exposure to radiation is reduced by the gate layer.

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 a non-insulating organic layer. The organic layer is directly on an amorphous selenium-based charge generator layer allowing charge transport across the layer, thereby reducing ghosting. 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.

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 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 a non-insulating organic layer. The organic layer is directly on an amorphous selenium-based charge generator layer allowing charge transport across the layer, thereby reducing ghosting. 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.