Abstract: A system and apparatus for classifying x-ray energy into discrete levels include an imaging system comprising an x-ray source, a detector, and a DAS having a discriminator assembly configured to count photon hits in the detector. A computer causes the discriminator assembly to count photon hits in the detector having an energy level greater than or equal to first and second threshold levels during an imaging scan, wherein the second threshold level is distinct from the first threshold level. The computer further modifies the counted photon hits having an energy level greater than or equal to the first threshold level based on the counted photon hits having an energy level greater than or equal to the second threshold level and reconstructs an image based on the modified photon hits and based on the counted photon hits having an energy level greater than or equal to a second threshold level.

Abstract: A system and apparatus for classifying x-ray energy into discrete levels include an imaging system comprising an x-ray source, a detector, and a DAS having a discriminator assembly configured to count photon hits in the detector. A computer causes the discriminator assembly to count photon hits in the detector having an energy level greater than or equal to first and second threshold levels during an imaging scan, wherein the second threshold level is distinct from the first threshold level. The computer further modifies the counted photon hits having an energy level greater than or equal to the first threshold level based on the counted photon hits having an energy level greater than or equal to the second threshold level and reconstructs an image based on the modified photon hits and based on the counted photon hits having an energy level greater than or equal to a second threshold level.

Abstract: An imaging system includes an x-ray source, a detector that receives x-rays emitted from the x-ray source, a DAS configured to count photon hits in the detector that occur at photon energies above at least a low keV threshold, a medium keV threshold, and a high keV threshold, and a computer operably coupled to the DAS. The computer is programmed to vary each of the medium keV threshold and the high keV threshold over a continuous keV range during data acquisition to define low, medium, and high keV bins that are based on the low, medium, and high keV thresholds, obtain photon counts in the low, medium, and high keV bins in a plurality of keV threshold combinations, calculate a noise variance as a function of at least one of the keV thresholds, and identify a noise minimum and low, medium, and high keV thresholds that correspond thereto.

Abstract: An imaging system includes an x-ray source, a detector that receives x-rays emitted from the x-ray source, a DAS configured to count photon hits in the detector that occur at photon energies above at least a low keV threshold, a medium keV threshold, and a high keV threshold, and a computer operably coupled to the DAS. The computer is programmed to vary each of the medium keV threshold and the high keV threshold over a continuous keV range during data acquisition to define low, medium, and high keV bins that are based on the low, medium, and high keV thresholds, obtain photon counts in the low, medium, and high keV bins in a plurality of keV threshold combinations, calculate a noise variance as a function of at least one of the keV thresholds, and identify a noise minimum and low, medium, and high keV thresholds that correspond thereto.