Abstract: An X-ray detector system includes a photon-counting detector with multiple detector modules including a respective power-consuming circuitry. At least some of the detector modules include a temperature sensor to monitor a temperature on the detector module and generate a temperature representing signal. A detector controller selectively switches, for at least a subset of the detector modules, the detector modules between an idle mode in which at least a respective part of the detector modules is powered off and an operational mode in which the detector modules are powered on. The power-consuming circuitries of the at least a subset of detector modules generate calibration data based on the temperature representing signals to correct for any temperature-induced changes to image data generated by the photon-counting detector.

Abstract: There is provided a method and an arrangement for determining a position of interaction of a photon in an individual detector diode of a photon-counting x-ray detector. The method includes determining the position of interaction in the detector diode based on pulse characteristics of a pulse generated by the individual detector diode in response to the photon interaction.

Abstract: Disclosed is an x-ray sensor having an active detector region including a plurality of detector diodes at a first side of the sensor, and with placement of the junction termination at a second opposite side of the sensor. Normally, this implies that the junction termination is moved from the top side where the active detector area is located to the bottom side of the sensor, allowing for full utilization of the active detector area at the top side with detector diodes to the very edge of the sensor.

Abstract: Disclosed is an x-ray detector system including a multitude of detector elements, each connected to a respective photon counting channel for providing at least one photon count output, and a read-out unit connected to the photon counting channels for outputting the photon count outputs. Each one of at least a subset of the photon counting channels includes at least two photon counting sub-channels, each photon counting sub-channel providing at least one photon count output and having a shaping filter, wherein the shaping filters of the photon counting sub-channels are configured with different shaping times, and wherein the photon counting sub-channels, having shaping filters with different shaping times, are adapted for counting photons of different energy levels. Furthermore, the read-out unit is configured to select, for each photon counting channel, photon count outputs from the photon counting sub-channels.

Abstract: Disclosed is an x-ray detector system including a multitude of detector elements, each connected to a respective photon counting channel for providing at least one photon count output, and a read-out unit connected to the photon counting channels for outputting the photon count outputs. Each one of at least a subset of the photon counting channels includes at least two photon counting sub-channels, each photon counting sub-channel providing at least one photon count output and having a shaping filter, wherein the shaping filters of the photon counting sub-channels are configured with different shaping times, and wherein the photon counting sub-channels, having shaping filters with different shaping times, are adapted for counting photons of different energy levels. Furthermore, the read-out unit is configured to select, for each photon counting channel, photon count outputs from the photon counting sub-channels.

Abstract: Disclosed is an x-ray detector system including a multitude of detector elements, each connected to a respective photon counting channel for providing at least one photon count output, and a read-out unit connected to the photon counting channels for outputting the photon count outputs. Each one of at least a subset of the photon counting channels includes at least two photon counting sub-channels, each photon counting sub-channel providing at least one photon count output and having a shaping filter, wherein the shaping filters of the photon counting sub-channels are configured with different shaping times, and wherein the photon counting sub-channels, having shaping filters with different shaping times, are adapted for counting photons of different energy levels. Furthermore, the read-out unit is configured to select, for each photon counting channel, photon count outputs from the photon counting sub-channels.

Abstract: There is provided an x-ray detector including a number of adjacent detector modules arranged in a configuration having central parts and peripheral parts. The x-ray detector is configured to have higher dose efficiency in the central parts and lower dose efficiency in the peripheral parts.

Abstract: Disclosed are methods and devices for estimating object scatter and/or internal scatter in a multi-level photon-counting x-ray detector, as well as x-ray tomographic imaging while correcting for object and internal scatter. The x-ray detector has at least two layers of detector diodes mounted in an edge-on geometry, e.g. designed for 1) estimating the object scatter contribution to the counts in a top layer of the at least two layers based on difference(s) in counts between the top layer and lower layer(s) under the assumption the object scatter has a slowly varying spatial distribution, and/or 2) estimating counts from reabsorption of photons that have Compton scattered inside the detector based on selectively blinding some detector elements from primary radiation by placing a highly attenuating beam stop on top of the detector elements, in lower layer(s) or in both top layer and lower layer(s), and measuring the counts in those detector elements.

Abstract: A photon-counting detector includes a first subset of detector modules and at least one second subset of detector modules. Each detector module has power-consuming circuitry. Power-consuming circuitry of detector modules in the first subset is configured, in an operational mode in which the detector modules are powered on, to consume a first amount of power. Correspondingly, power-consuming circuitry of detector modules in the at least one second subset is configured, in the operational mode, to consume a second amount of power that is lower than the first amount of power.

Abstract: There is provided an x-ray detector including a number of adjacent detector modules arranged in a configuration having central parts and peripheral parts. The x-ray detector is configured to have higher dose efficiency in the central parts and lower dose efficiency in the peripheral parts.

Abstract: Disclosed are methods and devices for estimating object scatter and/or internal scatter in a multi-level photon-counting x-ray detector, as well as x-ray tomographic imaging while correcting for object and internal scatter. The x-ray detector has at least two layers of detector diodes mounted in an edge-on geometry, e.g. designed for 1) estimating the object scatter contribution to the counts in a top layer of the at least two layers based on difference(s) in counts between the top layer and lower layer(s) under the assumption the object scatter has a slowly varying spatial distribution, and/or 2) estimating counts from reabsorption of photons that have Compton scattered inside the detector based on selectively blinding some detector elements from primary radiation by placing a highly attenuating beam stop on top of the detector elements, in lower layer(s) or in both top layer and lower layer(s), and measuring the counts in those detector elements.

Abstract: There is provided a method and corresponding system and apparatus for image reconstruction based on image data from a photon-counting multi-bin x-ray detector. The method includes determining (S1) parameter(s) of a given functional form of the relationship between comparator settings expressed in voltage in the read-out chain of the x-ray detector and the corresponding energy threshold values expressed in energy based on a fitting procedure between a first set of data representative of a measured pulse height spectrum and a second set of data representative of a reference pulse height spectrum. The method also includes performing (S2) image reconstruction based on the image data and the determined parameter(s). In this way, efficient high-quality image reconstruction can be achieved.

Abstract: The proposed technology relates to an x-ray detector arrangement having x-ray detector sub-modules arranged in two or more layers, where the separation between adjacent sub-modules in a lower layer is smaller than the corresponding separation between sub-modules in an upper layer.

Abstract: There is provided an arrangement (100) for enabling assessment of scoliosis. The arrangement (100) is configured to obtain at least one x-ray image by means of one or more photon-counting x-ray detectors. The arrangement (100) is further configured to determine at least one characteristic of the spine of a patient having possible scoliosis based on said at least one x-ray image obtained by means of the photon-counting x-ray detector(s) to enable assessment of scoliosis.

Abstract: There is provided a method and corresponding system and apparatus for image reconstruction based on image data from a photon-counting multi-bin x-ray detector. The method includes determining (S1) parameter(s) of a given functional form of the relationship between comparator settings expressed in voltage in the read-out chain of the x-ray detector and the corresponding energy threshold values expressed in energy based on a fitting procedure between a first set of data representative of a measured pulse height spectrum and a second set of data representative of a reference pulse height spectrum. The method also includes performing (S2) image reconstruction based on the image data and the determined parameter(s). In this way, efficient high-quality image reconstruction can be achieved.

Abstract: Disclosed are methods and devices for estimating object scatter and/or internal scatter in a multi-level photon-counting x-ray detector, as well as x-ray tomographic imaging while correcting for object and internal scatter. The x-ray detector has at least two layers of detector diodes mounted in an edge-on geometry, e.g. designed for 1) estimating the object scatter contribution to the counts in a top layer of the at least two layers based on difference(s) in counts between the top layer and lower layer(s) under the assumption the object scatter has a slowly varying spatial distribution, and/or 2) estimating counts from reabsorption of photons that have Compton scattered inside the detector based on selectively blinding some detector elements from primary radiation by placing a highly attenuating beam stop on top of the detector elements, in lower layer(s) or in both top layer and lower layer(s), and measuring the counts in those detector elements.

Abstract: There is provided a detector module (1) for a modular x-ray detector, wherein the detector module (1) includes multiple x-ray detector substrates (10) and associated anti-scatter collimators (20). Each x-ray detector substrate (10) has a number of detector diodes, and each x-ray detector substrate has an associated anti-scatter collimator (20). Each x-ray detector substrate (10) has an integrated circuit (30) for collecting x-ray signals from the diodes attached to the x-ray detector substrate at the bottom of the x-ray detector substrate assuming the top is where the x-rays enter, and the associated anti-scatter collimator (20) is placed above the integrated circuit (30).

Abstract: The proposed technology relates to an x-ray detector arrangement having x-ray detector sub-modules arranged in two or more layers, where the separation between adjacent sub-modules in a lower layer is smaller than the corresponding separation between sub-modules in an upper layer.

Abstract: The present invention relates to a method and an X-ray apparatus comprising an X-ray source, an x-ray detector, and at least a first collimator having a first active position and a second collimator having a second active position for forming a bundle of X-ray beams, wherein both of said active positions are located in a substantially straight path between said X-ray source and said detector, but at different distances from said X-ray source. The X-ray apparatus further comprises a selector arrangement for switching one of said first or second collimators in said first or second active position, whereby when one of said first or second collimators is in an active position the other collimator is in an inactive position.

Abstract: The present invention relates to a method and an X-ray apparatus comprising an X-ray source, an x-ray detector, and at least a first collimator having a first active position and a second collimator having a second active position for forming a bundle of X-ray beams, wherein both of said active positions are located in a substantially straight path between said X-ray source and said detector, but at different distances from said X-ray source. The X-ray apparatus further comprises a selector arrangement for switching one of said first or second collimators in said first or second active position, whereby when one of said first or second collimators is in an active position the other collimator is in an inactive position.