Abstract: The invention relates to X-ray imaging. In order to improve flexibility, for example in relation with phase-contrast imaging, the X-ray imaging device (10) comprises an X-ray source arrangement for providing an X-ray beam (11). Further, it is provided at least one grating (13, 14) and a line detector (15) with a plurality of sensor lines, which sensor lines are each provided by a plurality of sensor elements, and which sensor lines are provided for detecting respective portions of the X-ray beam (11) passing the at least one grating during operation. The X-ray imaging device is arranged for moving the line detector (15) and an object (21) to be imaged relative to each other, such that in response to the portions of the X-ray beam a number of interference patterns are detectable at respective different relative positions of the line detector and the object for reconstructing an image of the object (21).

Abstract: The invention relates a photon counting device and method for counting photon interactions in a piece of converter material and addressing the issue of charge sharing. The occurrence of a charge sharing event is already detected upon the onset of the pulse, taking into consideration an onset of a pulse in a neighboring pixel within a preferably very short coincidence window. According to the invention, it is detected whether a pulse is being processed and one or more neighboring pixels are scouted to decide whether a simultaneous interaction has been registered within a very short coincidence window.

Abstract: In a conventional phase-contrast X-ray imaging system, a source grating G0 generates an array of partially coherent line sources which illuminate an object and thereafter phase grating G1. The periodicity in the phase grating is self-imaged at certain instances further away from the X-ray source and sampled by a mechanically movable third absorptive analyzer grating G2 before the demodulated fringe intensity is detected by a conventional X-5 ray detector. This application proposes to directly demodulate the fringe intensity using a structured scintillator having a plurality of slabs in alignment with sub-pixels of an optical detector layer, in combination with electronic signal read-out approaches. Therefore, a mechanically movable third absorptive analyzer grating G2 can be omitted from a phase-contrast X-ray imaging system.

Abstract: Apparatus and related method for dark-field imaging. The apparatus operates on projective intensities detected at a detector in different energy channels. An energy weighting is used to improve the signal to noise ratio. The model operates in a logarithmic domain.

Abstract: The present invention relates to X-ray imaging technology as well as image post-processing. Particularly, the present invention relates to a method for computer aided detection of structures in X-ray images as well as an X-ray system. A computer aided detection algorithm visibly determines tissue structures in X-ray image information and subsequently matches the shape of a determined tissue structure with a library of known tissue structures for characterizing the type of determined tissue structure. The determination of a tissue structure and thus the characterization of the type of the tissue structure may be enhanced when employing also spectral information, in particular energy information of the acquired X-ray image.

Abstract: The invention relates to a correction device (8) for a radiation detector (2) including detector elements each for detecting incident photons. The correction device (8) is configured to read detection signals representative of an incident photon flux detected by the detector elements for different incident photon fluxes, and an evaluation unit (11) configured to determine for each detector element a dead time of the detector element and a parameter representative of an effective area of the detector element on the basis of a collective evaluation of the detection signals of the respective detector element. Further, the correction device (8) is configured to determine for each detector element correction parameters to compensate for differences in the effective areas and in the dead times of the detector elements on the basis of the determined parameters representative of the effective area and the determined dead times of the detector elements.

Abstract: The present invention is directed towards a photon counting radiation detector (10) comprising an array of pixels (13) comprising a plurality of detection pixels (131) for detecting imaging information. At least one pixel of the array of pixels (132) is shielded from receiving radiation. A dark current is determined from the shielded pixel (132) and is used to compensate for dark current in the other, non-shielded pixels (131). Embodiments are directed to integrating pixel shielding within an Anti Scatter Grid or in a mask.

Abstract: An imaging system (100) includes a radiation source (108) that emits radiation that traverses an examination region and imageable drug eluting beads in tissue of interest located therein, a spectral detector array (110) detects radiation traversing the examination region and generates a signal indicative thereof, spectral processing circuitry (117) that spectrally resolves the signal based on a plurality of thresholds (122), and a reconstructor (128) that generates spectral volumetric image data corresponding the imageable drug eluting beads based on the spectrally resolved signal.

Abstract: A system and related method for X-ray phase contrast imaging. A signal model is fitted to interferometric measurment data. The fitting operation yields a Compton cross section and a photo-electric image. A pro-portionality between the Compton cross section and electron-density is used to achieve a reduction of the number of fitting variables. The Compton image may be taken, up to a constant, as a phase contrast images.

Abstract: The invention relates a photon counting device and method for counting photon interactions in a piece of converter material and addressing the issue of charge sharing. The occurrence of a charge sharing event is already detected upon the onset of the pulse, taking into consideration an onset of a pulse in a neighboring pixel within a preferably very short coincidence window. According to the invention, it is detected whether a pulse is being processed and one or more neighboring pixels are scouted to decide whether a simultaneous interaction has been registered within a very short coincidence window.

Abstract: A phase contrast imaging apparatus (MA) and related image processing method. The imaging apparatus includes a movable arm (AR) that carries a detector (D) and one or more interferometric gratings (G0,G1,G2). The imaging apparatus includes a rigidizer (RGD) to control the rigidity of at least the arm (AR) or a mounting (GM) for the gratings (G0,G1,G2). This allows controlling a drift of a Moiré pattern as detected in a sequence of readouts. A phase of the so controlled Moiré pattern can be used to calibrate the imaging apparatus by using the image processing method.

Abstract: The invention relates to an X-ray detector device (10) for detection of X-ray radiation at an inclined angle relative to the X-ray radiation, an X-ray imaging system (1), an X-ray imaging method, and a computer program element for controlling such an X-ray imaging system for performing such method and a computer readable medium having stored such computer program element. The X-ray detector device (10) comprises a cathode surface (11) and an anode surface (12). The cathode surface (11) and the anode surface (12) are displaced by a separation layer (13) allowing charge transport (T) between the cathode surface (11) and the anode surface (12) in response to X-ray radiation incident during operation on the cathode surface (11). The anode surface (12) is segmented into anode pixels (121) and the cathode surface (11) is segmented into cathode pixels (111).

Abstract: The invention relates to a detection values determination system, especially for photon-counting CT scanners, comprising a detection pulse providing unit for providing detection pulses for an array of detection pixels 17, which is provided with an anti-charge-sharing grid 15 for suppressing charge sharing between different clusters 14 of the detection pixels, wherein the detection pulses are indicative of the energy of photons incident on the detection pixels. Charge-sharing-corrected detection values are determined based on the provided detection pulses, wherein for determining a charge-sharing-corrected detection value for a detection pixel of a cluster only detection pixels of the same cluster are considered. This allows for a relatively high detective quantum efficiency, wherein the technical efforts for providing the charge sharing correction can be relatively low.

Abstract: The present invention is directed towards a photon counting radiation detector (10) comprising an array of pixels (13) comprising a plurality of detection pixels (131) for detecting imaging information. At least one pixel of the array of pixels (132) is shielded from receiving radiation. A dark current is determined from the shielded pixel (132) and is used to compensate for dark current in the other, non-shielded pixels (131). Embodiments are directed to integrating pixel shielding within an Anti Scatter Grid or in a mask.

Abstract: The present invention relates to a dual- or multi-source CT system and method. For suppressing or even completely eliminating the negative effects of cross-scatter, the proposed CT system comprises two x-ray sources (10, 11), two detectors (13, 14), two read-out units (15, 16), a control unit (17) and a reconstruction unit (19). Further, a scatter correction unit (18) is provided or the read-out units (15, 16) are configured to generate scatter-corrected read-out signals from the detected radiation, wherein a scatter-corrected read-out signal is generated from the radiation detected by a detector during a single projection interval (I) including multiple repetitions of three phases, in which the sources are alternately switched on and off and in which the read-out units alternately register primary radiation or cross-scatter radiation.

Abstract: Photon-counting x-ray detectors (3) suffer from a degradation of their performance due to polarization. In order to correct the effects of polarization to the generated x-ray images, the invention suggests (i) exposing the radiation detector (3) to a first radiation pulse emitted by a further radiation source (11) and obtaining a first electric pulse signal generated by the radiation detector (3) in response thereto, (ii) later exposing the 5 radiation detector (3) to a second radiation pulse emitted by the further radiation source (11) during the acquisition of the image and obtaining a second electric pulse signal generated by the radiation detector (3) in response thereto, and (iii) comparing amplitudes of the first and second electric pulse signals and generating the x-ray image based on a result of the comparison. The invention provides a corresponding x-ray device and a corresponding method.

Abstract: An imaging system (100) includes a radiation source (110) with a focal spot (204) that emits a beam of x-ray photons that traverses an examination region (106). The imaging system further includes a photon counting detector array (122) that detects a sub-set of the x-ray photons that traverse an examination region. The imaging system further includes a controller (116) that generates and transmits a pause signal, in response to a calculated drop in an intensity of the emitted the beam of x-ray photons below a predetermined intensity level, which causes the photon counting detector array to pause detecting the sub-set of the x-ray photons. The imaging system further includes a counter (136) that counts, for each of a plurality of counting periods, the x-ray photons of the sub-set detected by the photon counting detector array in the corresponding counting period.

Abstract: The invention relates to a method and a pulse processing circuit (100) for the processing of current pulses (CP) generated by incident photons (X) in a piece of converter material, for instance in a pixel (11) of a radiation detector. Deviations of the pulse shape from a reference are detected and used to identify pulse corruption due to pile-up effects at high count rates and/or charge sharing between neighboring pixels. The deviation detection may for instance be achieved by generating, with a pulse shaper (110), bipolar shaped pulses from the current pulse (CP) and/or two shaped pulses of different shapes which can be compared to each other.

Abstract: The present invention relates to a detector (22?) for detecting ionizing radiation, comprising: a directly converting semi-conductor layer (36) for producing charge carriers in response to incident ionizing radiation; and a plurality of electrodes (34) corresponding to pixels for registering the charge carriers and generate a signal corresponding to registered charge carriers; wherein an electrode of the plurality of electrodes (34) is structured to two-dimensionally intertwine with at least two adjacent electrodes to register the charge carriers by said electrode and by at least one adjacent electrode. The present invention further relates to a detection method and to an imaging apparatus.

Abstract: Apparatus and related method for dark-field imaging. The apparatus operates on projective intensities detected at a detector in different energy channels. An energy weighting is used to improve the signal to noise ratio. The model operates in a logarithmic domain.