Abstract: A material decomposition apparatus for performing decomposition of a material in an object. The apparatus includes a data storage section for storing correction data preliminarily generated by decomposing one of three or more materials into the other two materials, a data input section to which radiation data of the object is inputted, the radiation data being divided into a plurality of energy levels, and a decomposition processing section for repeatedly performing two-material decomposition for decomposition of the other two materials of the three or more materials using the radiation data at different energy levels and the correction data to perform decomposition of the inside of the object into the three or more materials.

Abstract: There is provided a PCCT apparatus capable of correcting a band artifact of one material decomposition image and a band artifact of another material decomposition image. The PCCT apparatus obtains projection data divided into plural energy bins by irradiating a subject with X-rays, and includes: a first correction unit that corrects a band artifact of a first material decomposition image among plural material decomposition images created on the basis of the projection data, and calculates a first correction amount that is a correction amount for the band artifact; an energy calculation unit that calculates an average energy of X-rays that transmit the subject; and a second correction unit that corrects the band artifact of a second material decomposition image using a second correction amount that is a correction amount calculated on the basis of the first correction amount and the average energy.

Abstract: An X-ray CT apparatus and a correction method of projection data that are capable of suppressing artifacts generated in the vicinity of an edge portion of a test subject are provided. The X-ray CT apparatus for photographing a test subject is characterized by comprising: a correction data creation unit that creates correction data using difference data between measurement projection data for each X-ray energy obtained by photographing a known phantom having a known composition, a known shape, and a size smaller than a photographing field of view of the X-ray CT apparatus and calculation projection data for each X-ray energy calculated on the basis of X-ray transmission lengths obtained from the shape of the known phantom; and a correction unit that corrects projection data for each X-ray energy of the test subject using the correction data.

Abstract: There are provided a phantom capable of reducing the time required to acquire calibration data even if a radiation field is large, a radiographic imaging device, and a method for calibrating a photon counting detector. A phantom, which is used in acquisition of calibration data for a photon counting detector that outputs an electric signal based on photon energy of incident radiation, includes a first basis material and a second basis material that are known materials. The first basis material has a smaller attenuation coefficient for the radiation than that of the second basis material. The first basis material varies in thickness in a stepwise fashion in a direction perpendicular to a radiation field of the radiation and, in each step, the step decreases in thickness with distance from a center of the radiation field in a direction of arrangement of detection elements of the photon counting detector.

Abstract: A radiation imaging device capable of reducing the number of measurement times of calibration data used in pile up correction while maintaining the accuracy of the pile up correction. The radiation imaging device has a photon counting type detector to output an electric signal corresponding to energy of an incident radiation photon. The radiation imaging device includes: an extraction unit that extracts a component by the number of pile ups from a material spectrum, as a photon energy spectrum, obtained by detecting a radioactive ray transmitted through a calibration member, formed by combining plural basal substances having different radiation attenuation coefficients, with the photon counting type detector; and a synthesis unit that generates a calibrated equivalent spectrum, as a photon energy spectrum to be collated with an imaging spectrum obtained by imaging a subject by synthesizing the components by the number of pile ups based on the imaging spectrum.

Abstract: An X-ray CT device and a computing unit to use a projection-based method for image reconstruction are included. The computing unit sets a coordinate space having coordinate axes of the thicknesses of base materials and likelihood the thicknesses, and then based on X-ray attenuation responses, executes: a first search to search in a direction perpendicular to a ridge direction of likelihood contours for a first estimated thickness having the highest likelihood, starting with an estimated thickness input value set in the coordinate space; a second search to search for a second estimated thickness having the highest likelihood, starting with a shifted starting point at a position shifted from the estimated thickness input value; and a third search to search on a line connecting the first estimated thickness with the second estimated thickness for the highest likelihood estimator having the highest likelihood, to obtain an estimated thickness output value.

Abstract: A radiation imaging apparatus provided with a photon counting type detector for outputting an electric signal corresponding to energy of an incident radiation photon includes a measured value recording unit for measuring an attenuation value in the presence of a known calibration member while changing a threshold value of a detector output of the photon counting type detector and recording a measured value of the attenuation value for each threshold value of the detector output, a theoretical value calculation unit for calculating a theoretical value of the attenuation value in the presence of the calibration member with respect to multiple energies, a calibration information acquisition unit for acquiring a relation between the threshold value and the energy as calibration information by performing collation between the measured value and the theoretical value, and a calibration processing unit for converting the electric signal outputted from the photon counting type detector into energy.

Abstract: With the aim of providing a radiation imaging apparatus and a calibration method for photon counting detectors, being able to discriminate between soft and adipose tissues with high accuracy, there is disclosed a radiation imaging apparatus equipped with photon counting detectors which output an electric signal corresponding to photon energy which is energy of radiation photons incident thereon, the radiation imaging apparatus including a storage unit which stores relationships between linear attenuation coefficients and the photon energy with regard to multiple materials; a calculation unit which calculates normalized attenuation coefficients which are linear attenuation coefficients normalized by dividing linear attenuation coefficients per unit of photon energy by a linear attenuation coefficient at given photon energy with respect to each material; and a selection unit which selects basal materials which are used in relation to materials to be discriminated which are intended to be discriminated, based on

Abstract: With the aim of providing a radiation imaging apparatus and a calibration method for photon counting detectors, being able to discriminate between soft and adipose tissues with high accuracy, there is disclosed a radiation imaging apparatus quipped with photon counting detectors which output an electric signal corresponding to photon energy which is energy of radiation photons incident thereon, the radiation imaging apparatus including a storage unit which stores relationships between linear attenuation coefficients and the photon energy with regard to multiple materials; a calculation unit which calculates normalized attenuation coefficients which are linear attenuation coefficients normalized by dividing linear attenuation coefficients per unit of photon energy by a linear attenuation coefficient at given photon energy with respect to each material; and a selection unit which selects basal materials which are used in relation to materials to be discriminated which are intended to be discriminated, based on

Abstract: A material decomposition apparatus for performing decomposition of a material in an object. The apparatus includes a data storage section for storing correction data preliminarily generated by decomposing one of three or more materials into the other two materials, a data input section to which radiation data of the object is inputted, the radiation data being divided into a plurality of energy levels, and a decomposition processing section for repeatedly performing two-material decomposition for decomposition of the other two materials of the three or more materials using the radiation data at different energy levels and the correction data to perform decomposition of the inside of the object into the three or more materials.

Abstract: X-ray photons are counted as to each of energy bands (bins) to which optimum energy ranges are provided, and an image with reduced noise is displayed in a short time. An energy range of at least one of multiple energy bands in an X-ray detector is adjusted, on the basis of a distribution of degrees of X-ray attenuation at respective energy levels, the distribution of degrees of X-ray attenuation being measured in advance with respect to a predetermined direction of a subject. By using the X-ray detector with the energy bands after the adjustment, photon-counting CT imaging is performed.

Abstract: X-ray photons are counted as to each of energy bands (bins) to which optimum energy ranges are provided, and an image with reduced noise is displayed in a short time. An energy range of at least one of multiple energy bands in an X-ray detector is adjusted, on the basis of a distribution of degrees of X-ray attenuation at respective energy levels, the distribution of degrees of X-ray attenuation being measured in advance with respect to a predetermined direction of a subject. By using the X-ray detector with the energy bands after the adjustment, photon-counting CT imaging is performed.

Abstract: A radiation imaging apparatus provided with a photon counting type detector for outputting an electric signal corresponding to energy of an incident radiation photon includes a measured value recording unit for measuring an attenuation value in the presence of a known calibration member while changing a threshold value of a detector output of the photon counting type detector and recording a measured value of the attenuation value for each threshold value of the detector output, a theoretical value calculation unit for calculating a theoretical value of the attenuation value in the presence of the calibration member with respect to multiple energies, a calibration information acquisition unit for acquiring a relation between the threshold value and the energy as calibration information by performing collation between the measured value and the theoretical value, and a calibration processing unit for converting the electric signal outputted from the photon counting type detector into energy.

Abstract: A radiation imaging device capable of reducing the number of measurement times of calibration data used in pile up correction while maintaining the accuracy of the pile up correction. The radiation imaging device has a photon counting type detector to output an electric signal corresponding to energy of an incident radiation photon. The radiation imaging device includes: an extraction unit that extracts a component by the number of pile ups from a material spectrum, as a photon energy spectrum, obtained by detecting a radioactive ray transmitted through a calibration member, formed by combining plural basal substances having different radiation attenuation coefficients, with the photon counting type detector; and a synthesis unit that generates a calibrated equivalent spectrum, as a photon energy spectrum to be collated with an imaging spectrum obtained by imaging a subject by synthesizing the components by the number of pile ups based on the imaging spectrum.

Abstract: An X-ray CT device and a computing unit to use a projection-based method for image reconstruction are included. The computing unit sets a coordinate space having coordinate axes of the thicknesses of base materials and likelihood of said thicknesses, and then based on X-ray attenuation responses, executes: a first search to search in a direction perpendicular to a ridge direction of likelihood contours for a first estimated thickness having the highest likelihood, starting with an estimated thickness input value set in the coordinate space; a second search to search for a second estimated thickness having the highest likelihood, starting with a shifted starting point at a position shifted from the estimated thickness input value; and a third search to search on a line connecting the first estimated thickness with the second estimated thickness for the highest likelihood estimator having the highest likelihood, to obtain an estimated thickness output value.

Abstract: Provided is packaged medicine capable of inhibiting deterioration of electrodes over a long period of time and reliably transmitting a signal after ingestion even when a long period of time has elapsed since production to ingestion. The packaged medicine includes a solid medicine including drug powder and a micro-device, a container provided with a solid medicine accommodating space accommodating the solid medicine therein, and inert gas encapsulated in the solid medicine accommodating space. The micro-device includes two electrodes with mutually different ionization tendencies and a transmitter operable to transmit a signal using electromotive force generated when the electrodes come in contact with electrolyte.

Abstract: To provide an X-ray CT apparatus capable of correcting a difference of scattered radiation quantities contained in the projection data even in a case where a plurality of detection elements are disposed between collimator plates. The X-ray CT apparatus includes: an X-ray irradiation section for X-ray radiation; an X-ray detector including a plurality of detection elements for detecting the X-ray; a plurality of collimator plates disposed between the X-ray irradiation section and the X-ray detector so as to reduce scattered radiation; a reconstruction portion for reconstructing a tomographic image by using projection data generated based on an output from the X-ray detector; and a correction portion for correcting the projection data by using different correction functions according to the positions of the plural detection elements disposed between the collimator plates.

Abstract: Base substance thickness projection estimation values (124) and base substance thickness projection estimation error values (125) of M (M?N) base substances are estimated based on measured count projection values (121) using N energy windows for a subject. The base substance thickness projection estimated values (124) are updated such that a likelihood in accordance with a joint probability density of all of X-ray projection paths based on the base substance thickness projection estimated error values (125) increases. The obtained second base substance thickness projection assumed value (127) is subjected to back projection, thereby obtaining a base substance concentration image estimation value (128).

Abstract: A flat pixel (20) is a single unit composing a radiation detector and is configured so as to be divided into at least four subpixels (21) such that even if a prescribed number of subpixels (21) are removed from each pixel (20) in order of largest effective area, the centroid (51) of the effective area of the entirety of the remaining subpixels (21) is positioned within a similar-shape region (30) having the same centroid (50) as the pixel (20) and having sides of lengths that are half those of the pixel (20).

Abstract: A radiation imaging apparatus provided with a detector capable of improving correction accuracy at a high counting rate. The present invention is provided with: grids that remove scattered beams that emanate from an object; and a plurality of detector sub-pixels arranged so as to divide the gap between the grids into three or more segments, wherein the area of each of the detector sub-pixels located below the wall surface of the grids is larger than that of each of the other detector sub-pixels in a planar view. The size of each of the detector sub-pixels not located below the wall surface of the grids is expressed as (Pg?Tg?Lsplit×2)/N, where Pg represents the pitch between the grids, Tg represents the thickness of each of the grids, and N represents the number of segments formed by the detector sub-pixels between the grids.