Abstract: A method of calibrating a pixelated radiation detector containing a plurality of pixel detectors electrically connected to a plurality of respective read-out channels of detector read-out circuitry includes determining a sensor material deadtime, ?sensor, for each of the plurality of pixel detectors, and adjusting the respective read-out channel deadtime, ?ASIC, based on the determined sensor material deadtime, ?sensor, of the respective one of the plurality of pixel detectors, such that a total deadtime, ?total of each pixel detector including a sum of the respective sensor material deadtime, ?sensor, and the respective read-out channel deadtime, ?ASIC, varies by less than ±5% from each other.

Abstract: A method of X-ray imaging includes determining energies of photons emitted by an X-ray source and attenuated by an object that are detected by an energy-discriminating radiation detector, generating photon count data by counting a number of detected photons in a plurality of energy bins of the energy-discriminating radiation detector that includes a first energy bin and an adjacent second energy bin, and generating an X-ray image of the object using the photon count data. Detected photons determined to have an energy within a gap region between a maximum energy threshold of the first energy bin and a minimum energy threshold of the second energy bin are not included in the photon count data used to generate the X-ray image of the object.

Abstract: An X-ray radiation detector includes a semiconductor material plate, at least one cathode located on a first side of the semiconductor material plate, and at least one anode located on a second side of the semiconductor material plate. The semiconductor material plate thickness is at least 1.9 mm. The X-ray radiation detector is configured to operate at an absolute value of applied bias voltage of 1050 VDC to 1500 VDC, such that an electric field of at least 550 VDC/mm is generated in the semiconductor material plate.

Abstract: Various aspects include methods for use in X-ray detectors for adjusting count measurements from pixel detectors within a pixelated detector module to correct for the effects of pileup events that occur when more than one photon is absorbed in a pixel detector during a deadtime of the detector system. In various embodiments, count measurements may be obtained at two different X-ray tube currents, from which the detector system deadtime may be calculated based on the two count measurements and a ratio of the two X-ray tube currents. Using the calculated deadtime, a pileup correction factor may be determined appropriate for the behavior of the detector system in response to pileup events. The pileup correction factor may be applied to pixel detector count values after the counts have been corrected for pixel-to-pixel differences using a flat field correction.

Abstract: Various aspects include methods for compensating for the effects of charge sharing among pixelate detectors in X-ray detectors by applying a correspondence factor to counts of X-ray photons in energy bins to estimate incident X-ray photon energy bins. The correspondence factor may be determined by determining an incident X-ray photon energy spectrum, adjusting the incident X-ray photon energy spectrum to account for an energy resolution of the pixelated detector, generating a charge sharing model for the adjusted incident X-ray photon energy spectrum based on a percentage charge sharing parameter of the pixelated detector, applying the charge sharing model to energy bins of the pixelated detector to estimate counts in each of the energy bins, and determining the correspondence factor by comparing the estimated counts in each of the energy bins to counts in the energy bins that would be expected for the adjusting the incident X-ray photon energy spectrum.

Abstract: A set of N standard bin count distributions may be generated by irradiating a test radiation detector system with an X-ray beam attenuated by a respective one of N different K-edge filters for each of the at least one X-ray source energy setting. Energy bins of detectors of a target radiation detector system may be calibrated by generating measured bin count distributions for each calibration setting in which a respective one of the N different K-edge filters attenuates a source X-ray beam. Calibration parameters of the detectors of the target radiation detector system may be adjusted to match each of the measured bin count distributions to a corresponding standard bin count distribution. In addition, energy resolution of the radiation detectors can be measured and calibrated by fitting a portion of the measured X-ray spectrum near a K-edge to a fitting function.

Abstract: Various aspects include methods for use in X-ray detectors for adjusting count measurements from pixel detectors within a pixelated detector module to correct for the effects of pileup events that occur when more than one photon is absorbed in a pixel detector during a deadtime of the detector system. In various embodiments, count measurements may be obtained at two different X-ray tube currents, from which the detector system deadtime may be calculated based on the two count measurements and a ratio of the two X-ray tube currents. Using the calculated deadtime, a pileup correction factor may be determined appropriate for the behavior of the detector system in response to pileup events. The pileup correction factor may be applied to pixel detector count values after the counts have been corrected for pixel-to-pixel differences using a flat field correction.

Abstract: Various aspects include methods for compensating for the effects of charge sharing among pixelate detectors in X-ray detectors by applying a correspondence factor to counts of X-ray photons in energy bins to estimate incident X-ray photon energy bins. The correspondence factor may be determined by determining an incident X-ray photon energy spectrum, adjusting the incident X-ray photon energy spectrum to account for an energy resolution of the pixelated detector, generating a charge sharing model for the adjusted incident X-ray photon energy spectrum based on a percentage charge sharing parameter of the pixelated detector, applying the charge sharing model to energy bins of the pixelated detector to estimate counts in each of the energy bins, and determining the correspondence factor by comparing the estimated counts in each of the energy bins to counts in the energy bins that would be expected for the adjusting the incident X-ray photon energy spectrum.

Abstract: A set of N standard bin count distributions may be generated by irradiating a test radiation detector system with an X-ray beam attenuated by a respective one of N different K-edge filters for each of the at least one X-ray source energy setting. Energy bins of detectors of a target radiation detector system may be calibrated by generating measured bin count distributions for each calibration setting in which a respective one of the N different K-edge filters attenuates a source X-ray beam. Calibration parameters of the detectors of the target radiation detector system may be adjusted to match each of the measured bin count distributions to a corresponding standard bin count distribution. In addition, energy resolution of the radiation detectors can be measured and calibrated by fitting a portion of the measured X-ray spectrum near a K-edge to a fitting function.