Abstract: An X-ray system (2) for acquiring an image of an object has an X-ray detector (8), which is segmented into a plurality of neighboring detector tiles. In particular, the image can be a two-dimensional projection image but also a three-dimensional volume of the object reconstructed from a tomosynthesis acquisition. An X-ray detector moving mechanism (18) is adapted for moving the X-ray detector (8) at least between a first X-ray detector position and a second X-ray detector position during operation of the X-ray system. An X-ray source (4), a collimator (22) and the X-ray detector (8) of the X-ray system (2) are adapted for acquiring a plurality of partial X-ray images through the adjacent detector tiles while irradiating the object with X-ray beams from a plurality of tomographic angles ?. The processing unit is adapted for generating a two-dimension image of the object and/or for reconstructing a three-dimensional volume of the object from the acquired partial images.

Abstract: The invention relates to an X-ray imaging apparatus (2), comprising: a source (4) for generating X-ray radiation, an object receiving space (6) for arranging an object of interest for X-ray imaging, an X-ray collimator arrangement (8) arranged between the source (4) and the collimator arrangement (8), and an X-ray mirror arrangement (10). The mirror arrangement (10) comprises for example two tapered mirrors (22) facing each other and adapted for guiding X-ray radiation of the source (4) to the collimator arrangement (8). Consequently, the X-ray intensity at the object receiving space (6) is increased. In order to limit the X-ray radiation to an area, where the X-ray radiation can be utilized form imaging, an angle of spread ?m between the mirrors (22) and a length LM of each mirror (22) is adapted, such that a number of total reflections of X-ray radiation, provided by the source (4), at the mirrors (22) is limited.

Abstract: The present invention relates to differential phase-contrast imaging, in particular to a structure of a diffraction grating, e.g. an analyzer grating and a phase grating, for X-ray differential phase-contrast imaging. In order to make better use of the X-ray radiation passing the object, a diffraction grating (14) for X-ray differential phase-contrast imaging is provided with at least one portion (24) of a first sub-area (26) and at least one portion (28) of a second sub-area (30). The first sub-area comprises a grating structure (54) with a plurality of bars (34) and gaps (36) being arranged periodically with a first grating pitch P G (38), wherein the bars are arranged such that thy change the phase and/or amplitude of an X-ray radiation and wherein the gaps are X-ray transparent. The second sub-area is X-ray transparent and wherein the at least one portion of the second sub-area provides an X-ray 1 transparent aperture (40) in the grating.

Abstract: The present invention relates to a modulation of X-ray radiation for the purposes of imaging an object of interest. For the modulation, the X-ray radiation provided by an X-ray source (12) is in part totally reflected by a mirror (20). Thus, an X-ray radiation at an object receiving space (16) is formed by an unreflected X-ray radiation (24) and a reflected X-ray radiation (26). The mirror (20) is displaceable by an actuator (28), such that the intensity of the reflected X-ray radiation (26) can be adjusted, in particular to a density of the object to be imaged.

Abstract: An X-ray detector comprises a directly converting semiconductor layer having a plurality of pixels for converting incident radiation into electrical measurement signals with a band gap energy characteristic of the semiconductor layer, wherein said incident radiation is x-ray radiation emitted by an x-ray source or light omitted by at least one light source. An evaluation unit calculates evaluation signals per pixel or group of pixels from first electrical measurement signals generated when light from said at least one light source at a first intensity is coupled into the semiconductor layer, and second electrical measurement signals generated when light from said at least one light source at a second intensity is coupled into the semiconductor layer. A detection unit determines detection signals from electrical measurement signals generated when x-ray radiation is incident onto the semiconductor layer, and a calibration unit calibrates the detection unit on the basis of the evaluation signals.

Abstract: The intensity of an X-ray signal received at a detector after passing through an object of interest is a function of the attenuation, phase change, and scattering caused by the object of interest. In traditional X-ray systems, it was not possible to resolve these components. This application discusses an X-ray measurement technique which is insensitive to the variations in the interferometric pattern caused by phase differences in portions of the object of interest. Thus, received intensity measurements are caused only by attenuation and scattering components. By making two independent measurements of the object of interest using such a phase-invariant imager, the attenuation and scattering components may be separated, providing valuable extra information about the imaged object of interest arising from so-called “dark field” effects.

Abstract: An apparatus and related method for processing image data supplied by a scanning phase contrast or dark-field imaging apparatus (MA). Beam hardening artifact in phase contrast and dark-field imaging can be reduced by applying a beam hardening processing operation by a beam hardening processing module (BHC) in respect of a plurality of detector readings that contribute signals to the same image pixel position or geometric ray of an imaging region of the apparatus (MA). In one embodiment, a phantom body (PB) is used to acquire calibration data on which the beam hardening processing is based.

Abstract: A method includes analyzing a spectral projection image of a portion of a subject, generating a value quantifying an amount of a target specific contrast material in a region of interest of the spectral projection image, and generating a signal indicative of a presence of the target in response to the value satisfying a predetermined threshold level.

Abstract: An achromatic phase-contrast imaging apparatus for examining an object of interest is provided which comprises two different phase gratings which have different pitches. Thus, the imaging apparatus yields phase-contrast information for two different energies. Thus, phase-information over a wider energy band can be used.

Abstract: The present invention relates to differential phase-contrast imaging, in particular to a structure of a diffraction grating, e.g. an analyzer grating and a phase grating, for X-ray differential phase-contrast imaging. In order to provide enhanced phase-gradient based image data, a diffraction grating (14, 15) for X-ray differential phase-contrast imaging, is provided with a first sub-area (23) comprising at least one portion (24) of a first grating structure (26) and at least one portion (28) of a second grating structure (30). The first grating structure comprises a plurality of bars (34) and gaps (36) with a first grating orientation GO1 (37), being arranged periodically, wherein the bars are arranged such that they change the phase and/or amplitude of an X-ray radiation and wherein the gaps are X-ray transparent.

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: The present invention relates to a method and apparatus for X-ray phase contrast imaging. The method comprises the following steps: from the measured phase gradient and overall attenuation information, an electron density is computed; the contribution pc of the Compton scattering to the overall attenuation is estimated from the electron density; the contribution pp of the photo-electric absorption to the overall attenuation is estimated from the overall attenuation and the contribution pc; the values pc and pp are used to reconstruct a Compton image and a photo-electric image; by linear combination of these two images, a monochromatic image at a desired energy is obtained.

Abstract: The present invention relates to calibration in X-ray phase contrast imaging. In order to remove the disturbance due to individual gain factors, a calibration filter grating (10) for a slit-scanning X-ray phase contrast imaging arrangement is provided that comprises a first plurality of filter segments (11) comprising a filter material (12) and a second plurality of opening segments (13). The filter segments and the opening segments are arranged alternating as a filter pattern (15). The filter material is made from a material with structural elements (14) comprising structural parameters in the micrometer region. The filter grating is movably arranged between an X-ray source grating (54) and an analyzer grating (60) of an interferometer unit in a slit-scanning system of a phase contrast imaging arrangement. The slit-scanning system is provided with a pre-collimator (55) comprising a plurality of bars (57) and slits (59). The filter pattern is aligned with the pre-collimator pattern (61).

Abstract: The invention relates to a system (31) for generating spectral computed tomography projection data. A spectral projection data generation device (6) comprising an energy-resolving detector generates spectral computed tomography projection databased on polychromatic radiation (4), which has been provided by a radiation device (2), after having traversed an examination zone (5), and a reference values generation device generates energy-dependent reference values based on radiation, which has not traversed the examination zone. A spectral parameter providing unit (12) provides a spectral parameter being indicative of a spectral property of the radiation device based on the energy-dependent reference values.

Abstract: An imaging system includes a radiation source (108) configured to rotate about an examination region (106)and emit radiation that traverses the examination region. The imaging system further includes an array of radiation sensitive pixels (112) configured to detect radiation traversing the examination region and output a signal indicative of the detected radiation. The array of radiation sensitive pixels is disposed opposite the radiation source, across the examination region. The imaging system further includes a rigid flux filter device (130) disposed in the examination region between the radiation source and the radiation sensitive detector array of photon counting pixels. The rigid flux filter device is configured to filter the radiation traversing the examination region and incident thereon. The radiation leaving the rigid flux filter device has a predetermined flux.

Abstract: The invention relates to a source-detector arrangement (11) of an X-ray apparatus (10) for grating based phase contrast computed tomography. The source-detector arrangement comprises an X-ray source (12) adapted for rotational movement around a rotation axis (R) relative to an object (140) and adapted for emittance of an X-ray beam of coherent or quasi-coherent radiation in a line pattern (21); and an X-ray detection system (16) including a first grating element (24) and a second grating element (26) and a detector element (6); wherein the line pattern of the radiation and a grating direction of the grating elements are arranged orthogonal to the rotation axis; and wherein the first grating element has a first grating pitch varied dependent on a cone angle (?) of the X-ray beam and/or the second grating element has a second grating pitch varied dependent on the cone angle of the X-ray beam.

Abstract: The present invention relates to determining baseline shift of an electrical signal generated by a photon detector (102) of an X-ray examination device (101). For this purpose, the photon detector comprises a processing unit (103) that is configured to determine a first crossing frequency of a first pulse height threshold by the electrical signal generated by the photon detector. The first pulse height threshold is located at a first edge of a noise peak in the pulse height spectrum of the electrical signal.

Abstract: The invention relates to gratings for X-ray differential phase-contrast imaging, a focus detector arrangement and X-ray system for generating phase-contrast images of an object and a method of phase-contrast imaging for examining an object of interest. In order to provide gratings with a high aspect ratio but low costs, a grating for X-ray differential phase-contrast imaging is proposed, comprising a first sub-grating (112), and at least a second sub-grating (114; 116; 118), wherein the sub-gratings each comprise a body structure (120) with bars (122) and gaps (124) being arranged periodically with a pitch (a), wherein the sub-gratings (112; 114; 116; 118) are arranged consecutively in the direction of the X-ray beam, and wherein the sub-gratings (112; 114; 116; 118) are positioned displaced to each other perpendicularly to the X-ray beam.

Abstract: The invention relates to a detection apparatus (12) for detecting photons. The detection apparatus comprises a pile-up determining unit (15) for determining whether detection signal pulses being indicative of detected photons are caused by a pile-up event or by a non-pile-up event, wherein a detection values generating unit (16) generates detection values depending on the detection signal pulses and depending on the determination whether the respective detection signal pulse is caused by a pile-up event or by a non-pile-up event. In particular, the detection values generating unit can be adapted to reject the detection signal pulses caused by pile-up events while generating the detection values. This allows for an improved quality of the generated detection values.

Abstract: The invention relates to an X-ray detector arrangement (10) for X-ray phase contrast tomo-synthesis imaging, a line detector (1) for X-ray phase contrast tomo-synthesis imaging, an imaging system (24) for X-ray phase contrast tomo-synthesis imaging, a method for X-ray phase contrast tomo-synthesis imaging, and a computer program element for controlling such arrangement and a computer readable medium having stored such computer program element. The X-ray detector arrangement (10) comprises several line detectors (1). Each line detector (1) is configured to detect a Moiré pattern in at least a portion of an X-ray beam (2) impacting such line detector (1). Each line detector (1) comprises several detector lines (11), wherein a width W of each line detector (1) equals one period or an integer multiple of the period of the Moiré pattern.