Abstract: A diagnostic imaging system includes an x-ray source that emits a beam of x-ray energy toward an object to be imaged and an energy discriminating (ED) detector that receives the x-ray energy emitted by the x-ray energy source. The ED detector includes a first layer having a first thickness, wherein the first layer comprises a semiconductor configurable to operate in at least an integrating mode and a second layer having a second thickness greater than the first thickness, and configured to receive x-rays that pass through the first layer. The system further includes a data acquisition system (DAS) operably connected to the ED detector and a computer that is operably connected to the DAS. The computer is programmed to identify saturated data in the second layer and substitute the saturated data with non-saturated data from a corresponding pixel in the first layer.

Abstract: An application-specific integrated circuit (ASIC) comprising a plurality of channels, each channel having circuitry for time and energy discrimination, a plurality of programmable registers, each programmable register configured to output at least one configuration parameter for the circuitry, and a channel-select register configured to identify a channel of the plurality of channels to be configured. The ASIC further includes a configuration-select register configured to identify the programmable register to be used for channel configuration, and a communications interface configured to transmit instructions received from a controller to one of the channel-select register, the configuration-select register, and the plurality of programmable registers.

Abstract: An event time stamping system comprising a current source, an integrator comprising an input and an output, and configured to output a voltage proportional to the length of time the current source is coupled to the input, and one or more switches configured to couple the current source to the input of the integrator upon receipt of an event signal and configured to de-couple the current source from the input of the integrator upon receipt of a control trigger. The system further comprises a lock-out signal generator configured to generate a lock-out signal, and a controller coupled to the one or more switches, wherein the controller is configured to generate the control trigger based on the lock-out signal to ensure a minimum integration time.

Abstract: A diagnostic imaging system includes a high frequency electromagnetic energy source that emits a beam of high frequency electromagnetic energy toward an object to be imaged. An energy discriminating (ED) detector receives high frequency electromagnetic energy emitted by the high frequency electromagnetic energy source. The ED detector includes a direct conversion layer dynamically operable in a photon counting mode in one view and in an integrating mode in another view and an indirect conversion layer. A data acquisition system (DAS) is operably connected to the ED detector and a computer operably connected to the DAS.

Abstract: A CT detector includes a direct conversion material configured to generate electrical charge upon reception of x-rays, a plurality of metallized anodes configured to collect electrical charges generated in the direct conversion material, at least one readout device, and a redistribution layer having a plurality of electrical pathways configured to route the electrical charges from the plurality of metallized anodes to the at least one readout device. A plurality of switches is coupled to the plurality of electrical pathways between the plurality of metallized anodes and the at least one readout device, wherein each of the plurality of switches includes an input line electrically coupled to one of the plurality of metallized anodes, a first output node electrically coupled to the at least one readout device, and a second output node electrically coupled to at least one other switch of the plurality of switches.

Abstract: A diagnostic imaging system includes a high frequency electromagnetic energy source that emits a beam of high frequency electromagnetic energy toward an object to be imaged, a detector that receives high frequency electromagnetic energy emitted by the high frequency electromagnetic energy source, and a data acquisition system (DAS) operably connected to the detector. A computer is operably connected to the DAS and is programmed to generate corresponding sets of projection values for three or more energy spectra through employment of attenuation coefficients of three or more basis materials to simulate responses of the diagnostic imaging system to a plurality of lengths of the three or more basis materials wherein the three or more basis materials comprise two or more non K-edge basis materials and one or more K-edge basis materials.

Abstract: A photon-counting detector includes a direct conversion material constructed to directly convert an energy of at least one incident photon to an electrical signal indicative of the energy level of the at least one individual photon and a data acquisition system (DAS). The DAS includes a first comparator having a first signal level threshold that is less than an electrical signal level that is indicative of a maximum energy of a spectrum of photons, the first comparator configured to output a count when the electrical signal level exceeds the first signal level threshold, and a second comparator having a second signal level threshold that is greater than or equal to the electrical signal level indicative of the maximum energy of the spectrum of photons, the second comparator configured to output a count when the electrical signal exceeds the second signal level threshold.

Abstract: Count rates may be obtained from one or more subpixels for a given pixel in an imaging system detector. Count rates may be obtained from individual subpixels, or may be from electronically binned subpixels at least in part in various subpixel arrangements where a selected subpixel arrangement may be adaptively set according to a detected count rate. For lower count rates, two or more subpixels may be electronically binned together and the counts may be obtained from the binned subpixels, for example to mitigate a charge sharing effect. For higher count rates, the count rates of a greater number of subpixels may be individually obtained, for example to mitigate a pulse pile-up effect. Detective quantum efficiency may be optimized over a wider range of photon flux rate via the adaptive subpixel arrangement.

Abstract: A CT detector includes a plurality of metallized anodes with each metallized anode separated from another metallized anode by a gap. A direct conversion material is electrically coupled to the plurality of metallized anodes and has a charge sharing region in which an electrical charge generated by an x-ray impinging the direct conversion material is shared between at least two of the plurality of metallized anodes. An x-ray attenuating material is positioned to attenuate x-rays directed toward the charge sharing region.

Abstract: A CT detector capable of energy discrimination and direct conversion is disclosed. The detector includes multiple layers of semiconductor material with the layers having varying thicknesses. The detector is constructed to be segmented in the x-ray penetration direction so as to optimize count rate performance as well as avoid saturation. The detector also includes variable pixel pitch and a flexible binning of pixels to further enhance count rate performance.

Abstract: A system and method of density and effective atomic number imaging include a computer programmed to acquire projection data from the detector of an unknown material at the time of projection data acquisition. The computer is also programmed to generate a density image for the unknown material based on a calibration of two or more known basis materials and to generate an effective atomic number (Z) for the unknown material based on the calibration of two or more known basis materials and based on a function arctan of a ratio of atomic numbers of the two or more known basis materials. The density and effective atomic number images are stored to a computer readable storage medium.

Abstract: A CT imaging system includes a rotatable gantry having an opening to receive an object to be scanned, a first x-ray emission source attached to the rotatable gantry and configured to emit x-rays toward the object, and a second x-ray emission source attached to the rotatable gantry and configured to emit x-rays toward the object. A first detector is configured to receive x-rays that emit from the first x-ray emission source, and a second detector configured to receive x-rays that emit from the second x-ray emission source. A first portion of the first detector is configured to operate in an integration mode and a first portion of the second detector is configured to operate in at least a photon-counting mode.

Abstract: A diagnostic imaging system includes a high frequency electromagnetic energy source that emits a beam of high frequency electromagnetic energy toward an object to be imaged. An energy discriminating (ED) detector receives high frequency electromagnetic energy emitted by the high frequency electromagnetic energy source. The ED detector includes a direct conversion layer dynamically operable in a photon counting mode in one view and in an integrating mode in another view and an indirect conversion layer. A data acquisition system (DAS) is operably connected to the ED detector and a computer operably connected to the DAS.

Abstract: A diagnostic imaging system includes a high frequency electromagnetic energy source that emits a beam of high frequency electromagnetic energy toward an object to be imaged. An energy discriminating (ED) detector receives high frequency electromagnetic energy emitted by the high frequency electromagnetic energy source. The ED detector includes a first direct conversion layer and a second direct conversion layer. The first direct conversion layer comprises a first direct conversion material and the second direct conversion layer comprises a second direct conversion material that is different from the first direct conversion material. A data acquisition system (DAS) is operably connected to the ED detector and a computer operably connected to the DAS.

Abstract: A CT detector includes a plurality of metallized anodes with each metallized anode separated from another metallized anode by a gap. A direct conversion material is electrically coupled to the plurality of metallized anodes and has a charge sharing region in which an electrical charge generated by an x-ray impinging the direct conversion material is shared between at least two of the plurality of metallized anodes. An x-ray attenuating material is positioned to attenuate x-rays directed toward the charge sharing region.

Abstract: A detector module for a CT imaging system is provided. The detector module includes a sensor element to convert x-rays to electrical signals. The sensor element is coupled to a data acquisition system (DAS) via an interconnect system, the DAS comprised of an electronic substrate and an integrated circuit. The interconnect system couples the sensor element, electronic substrate, and integrated circuit by way of a contact pad interconnect together with a wire bond interconnect or an additional contact pad interconnect.

Abstract: An adaptive data acquisition circuit (26) includes an amplifier (14) for amplifying electrical pulses generated by a detector (12) responsive to energy incident at the detector. The adaptive data acquisition circuit also includes a counting circuit (28) for counting amplified electrical pulses generated by the amplifier. In addition, the adaptive data acquisition circuit includes a digital logic circuit (30) for determining a pulse parameter indicative of a pulse rate and an amount of energy present in the amplified electrical pulses and for generating a control signal (34) responsive to the pulse parameter for controlling an operating parameter of the data acquisition circuit.

Abstract: A diagnostic imaging system in an example comprises a high frequency electromagnetic energy source, a detector, a data acquisition system (DAS), and a computer. The high frequency electromagnetic energy source emits a beam of high frequency electromagnetic energy toward an object to be imaged. The detector receives high frequency electromagnetic energy emitted by the high frequency electromagnetic energy source. The DAS is operably connected to the detector. The computer is operably connected to the DAS and programmed to employ a threshold to trigger a filter operation on a pixel, in a basis material decomposition (BMD) image of a plurality of BMD images, through comparison of an actual noise ratio between a pair of BMD images, of the plurality of BMD images, to a theoretical BMD noise ratio value. The computer operably connected to the DAS is programmed to employ a correlation in noise distribution of the plurality of BMD images to reduce image noise in the plurality of BMD images.

Abstract: An adaptive CT data acquisition system and technique is presented whereby radiation emitted for CT data acquisition is dynamically controlled to limit exposure to those detectors of a CT detector assembly that may be particularly susceptible to saturation during a given data acquisition. The data acquisition technique recognizes that for a given subject size and position that pre-subject filtering and collimating of a radiation beam may be insufficient to completely prevent detector saturation. Therefore, the present invention includes implementation of a number of CT data correction techniques for correcting otherwise unusable data of a saturated CT detector. These data correction techniques include a nearest neighbor correction, off-centered phantom correction, off-centered synthetic data correction, scout data correction, planar radiogram correction, and a number of others.

Abstract: An adaptive data acquisition circuit (26) includes an amplifier (14) for amplifying electrical pulses generated by a detector (12) responsive to energy incident at the detector. The adaptive data acquisition circuit also includes a counting circuit (28) for counting amplified electrical pulses generated by the amplifier. In addition, the adaptive data acquisition circuit includes a digital logic circuit (30) for determining a pulse parameter indicative of a pulse rate and an amount of energy present in the amplified electrical pulses and for generating a control signal (34) responsive to the pulse parameter for controlling an operating parameter of the data acquisition circuit.