Abstract: An x-ray detector for a medical imaging device includes an anti-scatter grid, a measuring layer including a regular arrangement of measuring cells, and an evaluation unit. The anti-scatter grid covers the measuring layer and is aligned toward a specific focal point. The evaluation unit is configured to determine a focal position of an x-ray source relative to the focal point based on a local intensity difference of x-rays striking the measuring layer.

Abstract: A method for adapting activation parameters used to generate a pulse sequence when activating a magnetic resonance system is provided. The method includes determining stimulation values for the pulse sequence based on predefined activation parameters. The stimulation values represent a stimulation exposure of a patient. Test regions that exhibit stimulation maxima are identified in the pulse sequence, and the identified test regions are tested with respect to compliance with a predefined stimulation limit value.

Abstract: A direct-converting x-ray radiation detector is disclosed for detecting x-ray radiation, in particular for use in a CT system. In an embodiment, the detector includes a semiconductor material used for detecting the x-ray radiation; at least one collimator; and at least one radiation source, to irradiate the semiconductor material with additional radiation. In at least one embodiment, the at least one collimator includes at least one reflection layer on a side facing the semiconductor material, on which the additional radiation is reflected to the semiconductor material. In another embodiment, a CT system including the direct-converting x-ray radiation detector, and a method for detecting incident x-ray radiation via a direct-converting x-ray radiation detector, in particular for use in a CT system, are disclosed.

Abstract: A method is disclosed for detecting x-rays using an x-ray detector which includes a direct-conversion semiconductor detector element. Additional radiation is supplied to the semiconductor detector element using a radiation source, and the supply of the additional radiation is controlled and/or regulated on the basis of a specified target value. In at least one embodiment, the target value can be specified in a variable manner over time as a sequence of target values. An x-ray detector system is further disclosed, with which the method can be carried out.

Abstract: A method is disclosed for transmitting measurement data from a transmitter system to a receiver system by way of a transmission link of a medical device. In an embodiment, the measurement data, as input data of a transformation method, is transformed to output values and, after transmission, back transformed again, the values of the input data lying between a maximum value and a minimum value and an assignment function being used for compression purposes, to allocate an output value to every value of the input data, a root function being used as the assignment function for at least some of the values.

Abstract: A quantum-counting radiation detector in which signals of individual pixels and signals of combined pixels are evaluated in parallel processing branches and count results are combined in an appropriate manner, thereby reducing the influence of unwanted interference effects for the respective application.

Abstract: A method and a computed tomography system are disclosed for generating tomographic image datasets of a measurement object. The computed tomography system includes at least two simultaneously operable sets of detector elements which jointly scan a measurement object from a multiplicity of projection angles in an integrating manner on the one hand and an energy-resolving manner on the other hand. In at least one embodiment, the method includes determining a first projection dataset from measurement data recorded in an integrating manner. Further, at least one second projection dataset is determined from energy-resolved measurement data, and in addition a weighted tomographic result image dataset is calculated based on weighted use of the first and the second projection dataset, the weighting being applied to the projection data or the tomographic image data reconstructed therefrom.

Abstract: A method is disclosed for energy calibrating quantum-counting x-ray detectors in an x-ray installation including at least two x-ray systems turnable around a center of rotation. A target, for producing x-ray fluorescence radiation, is positioned between the first x-ray source and first x-ray detector and irradiated with x-radiation of the first x-ray source in such a way that x-ray fluorescence radiation which strikes the second x-ray detector from the target is produced by the x-radiation of the first x-ray source. The second x-ray detector is then energy calibrated by way of the x-ray fluorescence radiation of the target. The first x-ray detector can be energy calibrated in the same way with the aid of the x-radiation of the second x-ray source. With the proposed method, the x-ray detectors of a dual-source CT x-ray installation can be calibrated with little expenditure under conditions close to those of the system.

Abstract: A detector arrangement of an imaging system detector detecting ionizing radiation includes a detector carrier, a plurality of detector modules attached to the detector carrier, and a collimator disposed in the radiation direction in front of the detector modules which are disposed on the incident radiation measurement side. In at least one embodiment, at least one air gap is included for conveying cooling air is disposed between the collimator and the measurement sensors of the detector modules. A method is also disclosed for cooling a detector arrangement of a detector rotating around a system axis with a plurality of measurement sensors disposed next to one another and a collimator arranged in the radiation direction in front of the measurement sensors, wherein cooling air is conveyed in or against the system axis direction between the collimator and the measurement sensors which directly cools the surface of the measurement sensors.

Abstract: In a method, with a current measurement, the history of the radiation exposure of the X-ray detector is taken into account with respect to the overall X-ray detector or subareas of the X-ray detector, in respect of a reduction in the measurement sensitivity produced as a result and a recovery of the reduction in the measurement sensitivity, and the determined measuring signal is corrected with a correction factor which is dependent on the history of the radiation exposure. Furthermore, an X-ray recording system includes a detector which includes a plurality of detector elements, which are read out in groups channel by channel and a read-out apparatus with computer-assisted device for correcting read-out detector data prior to a further processing of the detector data to form projective or tomographic images.

Abstract: A method and a dual-source CT are disclosed. In at least one embodiment, the projection data of the integrating and of the counting detector from a quarter rotation of the gantry is used jointly for reconstruction of a first tomographic image dataset, the energy-resolved projection data of the counting detector from at least one half rotation of the gantry being used for reconstruction of at least a second material-selective tomographic image dataset, and at least one tomographic result image dataset being formed by overlaying the first tomographic image dataset with the material selection of the second image dataset.

Abstract: A method is disclosed for homogenization of threshold values of a multichannel, quanta-counting radiation detector. In an embodiment of the method empty measurements are carried out with the detector at different spectral compositions of the radiation with different settings of threshold values of the comparators. For each channel of which the comparators is to be set to the same energy threshold, an adapted threshold value is determined for this energy threshold from the empty measurement, at which a variation of the normalized count rate of the channel is minimized over the different spectral compositions of the radiation. This avoids problems in the further processing of the measurement data of the detector, which can occur during alterations of the spectrum.

Abstract: An x-ray detector is disclosed, in particular for a medical imaging device. The x-ray detector includes an anti-scatter grid, a measuring layer including a regular arrangement of measuring cells, and an evaluation unit. The anti-scatter grid covers the measuring layer and is aligned toward a specific focal point. The evaluation unit is configured to determine a focal position of an x-ray source relative to the focal point based on a local intensity difference of x-rays striking the measuring layer. A medical imaging device including the x-ray detector is also disclosed, along with a method for operating the x-ray detector.

Abstract: A method and a computed tomography system are disclosed for generating tomographic image datasets of a measurement object with multiple simultaneously operable sets of detector elements. In at least one embodiment, at least one first set measures incident radiation over the entire energy spectrum of the incident radiation in an integrating manner and at least one second set measures incident radiation in at least two energy ranges in a resolving manner, wherein furthermore by way of the integrating measurements, the energy-resolving measurements relating in each case to rays traversing a measurement object in a spatially identical manner are corrected and a tomographic image dataset of the measurement object is reconstructed at least from the corrected energy-resolving measurements.

Abstract: A method is disclosed for energy calibrating quantum-counting x-ray detectors in an x-ray installation including at least two x-ray systems turnable around a center of rotation. A target, for producing x-ray fluorescence radiation, is positioned between the first x-ray source and first x-ray detector and irradiated with x-radiation of the first x-ray source in such a way that x-ray fluorescence radiation which strikes the second x-ray detector from the target is produced by the x-radiation of the first x-ray source. The second x-ray detector is then energy calibrated by way of the x-ray fluorescence radiation of the target. The first x-ray detector can be energy calibrated in the same way with the aid of the x-radiation of the second x-ray source. With the proposed method, the x-ray detectors of a dual-source CT x-ray installation can be calibrated with little expenditure under conditions close to those of the system.

Abstract: A method is disclosed for homogenization of threshold values of a multichannel, quanta-counting radiation detector. In an embodiment of the method empty measurements are carried out with the detector at different spectral compositions of the radiation with different settings of threshold values of the comparators. For each channel of which the comparators is to be set to the same energy threshold, an adapted threshold value is determined for this energy threshold from the empty measurement, at which a variation of the normalized count rate of the channel is minimized over the different spectral compositions of the radiation. This avoids problems in the further processing of the measurement data of the detector, which can occur during alterations of the spectrum.

Abstract: A method is disclosed for determining the intensity of ionizing radiation using a detector with a multiplicity of direct-conversion detector elements, in particular for use in a CT system. In at least one embodiment, the method includes supplying the signal pulses to a preamplifier/signal conditioner, supplying the amplified and conditioned signal pulses to two pulse-height discriminators connected in parallel or in series, registering by a combination logic, and transmitting the registered signal pulses to a counter. In at least one embodiment, provision is made for feedback, by which, firstly, the pulse shape of the signal pulses and, secondly, the clock rate of the clocked pulse-height discriminator are set as a function of the signal frequency.

Abstract: A detector arrangement of an imaging system detector detecting ionizing radiation includes a detector carrier, a plurality of detector modules attached to the detector carrier, and a collimator disposed in the radiation direction in front of the detector modules which are disposed on the incident radiation measurement side. In at least one embodiment, at least one air gap is included for conveying cooling air is disposed between the collimator and the measurement sensors of the detector modules. A method is also disclosed for cooling a detector arrangement of a detector rotating around a system axis with a plurality of measurement sensors disposed next to one another and a collimator arranged in the radiation direction in front of the measurement sensors, wherein cooling air is conveyed in or against the system axis direction between the collimator and the measurement sensors which directly cools the surface of the measurement sensors.

Abstract: A quantum-counting radiation detector is disclosed, in particular an x-ray detector. In at least one embodiment, the signals of the individual pixels and the signals of combined pixels are evaluated in parallel processing branches. It is then possible to combine the count results in an appropriate manner, to reduce the influence of unwanted interference effects for the respective application.

Abstract: A method and a computed tomography system are disclosed for generating tomographic image datasets of a measurement object with multiple simultaneously operable sets of detector elements. In at least one embodiment, at least one first set measures incident radiation over the entire energy spectrum of the incident radiation in an integrating manner and at least one second set measures incident radiation in at least two energy ranges in a resolving manner, wherein furthermore by way of the integrating measurements, the energy-resolving measurements relating in each case to rays traversing a measurement object in a spatially identical manner are corrected and a tomographic image dataset of the measurement object is reconstructed at least from the corrected energy-resolving measurements.