Abstract: Provided is an X-ray imaging apparatus capable of stabilizing polarization of a photon counting detector and suppressing ineffective exposure of a subject. An X-ray imaging apparatus comprises an X-ray source that irradiates an X-ray, a photon counting detector that counts an X-ray photon for each energy bin, and an image generation unit that generates a medical image of a subject based on a detector output from the photon counting detector. The X-ray imaging apparatus further comprises a control unit that checks, in a case where polarization of the photon counting detector is not stable, the subject not being present in an X-ray irradiation field which is a range where the X-ray is irradiated from the X-ray source and then causes the X-ray source to irradiate the photon counting detector with the X-ray.

Abstract: To provide a radiation imaging device which, even when a subpixel fails during operation of the photon counting detector, can correct an output signal of the pixel including the failed subpixel. A radiation imaging device that has a photon counting detector to count radiation photons and can correct an output signal of a pixel including a failed subpixel even if the subpixel fails during operation of the photon counting detector. The photon counting detector comprises: a pixel comprised of a plurality of subpixels; a data processing section that calculates an output signal of the pixel according to the number of radiation photons counted in each of the subpixels; and a failure detection section that detects a failure of the subpixel according to the number of radiation photons counted in the subpixel and outputs the position of the failed subpixel.

Abstract: A radiographic imaging apparatus and a radiation detector are provided, which are capable of sufficiently reducing the sensitivity difference between pixels even if the incident photon rate is high. A radiographic imaging apparatus includes: a radiation source for irradiating an object with radiation; a plurality of detection element modules each having a semiconductor layer that generates electrical charges depending on photon energy of the radiation, and a photon counting circuit for counting the electrical charges for each pixel; and a collimator that is disposed between the radiation source and the semiconductor layer, and has a plurality of walls forming a plurality of passage holes through which the radiation passes.

Abstract: There is provided a radiographic imaging apparatus capable of alignment of a detector with a collimator with a position of a radiation source fixed. The radiographic imaging apparatus includes the radiation source which irradiates a subject with radioactive rays, a plurality of detecting elements which detect photons in the radioactive rays, and a collimator which is disposed between the radiation source and the detecting elements and has a plurality of walls which form a plurality of passing holes that the radioactive rays pass. The detecting element and the collimator are aligned with each other in a direction which is orthogonal to a direction that the subject is irradiated with the radioactive rays such that a ratio or a difference between output signals from the detecting elements which are mutually adjacent with the wall being interposed falls within a predetermined range.

Abstract: There are provided a radiation detector module, a radiation detector, and a radiographic imaging apparatus which make it possible to increase the row number while suppressing a length in a body-axis direction. The radiation detector module includes a detector substrate on which a scintillator, a photodiode, and AD conversion chips are loaded, and a control substrate which supplies power to the detector substrate and controls the operation of an AD conversion unit (AFE) of each AD conversion chip of the detector substrate. The plurality of radiation detector modules configure a radiation detector which suppresses the length in the body-axis direction by connecting together the two substrates so as to form a two-stage structure by stacking connectors.

Abstract: There is provided a radiographic imaging apparatus capable of alignment of a detector with a collimator with a position of a radiation source fixed. The radiographic imaging apparatus includes the radiation source which irradiates a subject with radioactive rays, a plurality of detecting elements which detect photons in the radioactive rays, and a collimator which is disposed between the radiation source and the detecting elements and has a plurality of walls which form a plurality of passing holes that the radioactive rays pass. The detecting element and the collimator are aligned with each other in a direction which is orthogonal to a direction that the subject is irradiated with the radioactive rays such that a ratio or a difference between output signals from the detecting elements which are mutually adjacent with the wall being interposed falls within a predetermined range.

Abstract: There are provided a radiation detector module, a radiation detector, and a radiographic imaging apparatus which make it possible to increase the row number while suppressing a length in a body-axis direction. The radiation detector module includes a detector substrate on which a scintillator, a photodiode, and AD conversion chips are loaded, and a control substrate which supplies power to the detector substrate and controls the operation of an AD conversion unit (AFE) of each AD conversion chip of the detector substrate. The plurality of radiation detector modules configure a radiation detector which suppresses the length in the body-axis direction by connecting together the two substrates so as to form a two-stage structure by stacking connectors.

Abstract: The present invention provides a radiation imaging apparatus capable of maintaining the quality of an image obtained even when a dose incident on a radiation detector changes suddenly. The present invention is a radiation imaging apparatus including a radiation source, a radiation detector to detect radiation emitted from the radiation source, and a cooling unit to cool the radiation detector; and is characterized in that the radiation detector has a counting circuit to output a number of photons in radiation counted per unit time as a photon counting rate, and the cooling unit controls a coolability of the radiation detector in response to the photon counting rate.

Abstract: To provide a radiation imaging system which is adapted to downsize a photon counting radiation detector including a semiconductor layer for detecting photons of radiation and a collimator for suppressing incidence of scattered rays, and which ensures high voltage resistance. The radiation imaging system includes: a radiation source; a radiation detector; and a support portion for supporting the radiation source and the radiation detector in opposed relation. The system has a structure wherein the radiation detector includes a plurality of detecting element modules arranged in an arcuate form. The detecting element module includes a base fixed to the support portion; a semiconductor layer; a high-voltage wire for supplying high voltage to the semiconductor layer; a collimator for suppressing scattered rays, and a supporting column disposed at place within a predetermined distance from the semiconductor layer.

Abstract: To provide a radiation imaging system which is adapted to downsize a photon counting radiation detector including a semiconductor layer for detecting photons of radiation and a collimator for suppressing incidence of scattered rays, and which ensures high voltage resistance. The radiation imaging system includes: a radiation source; a radiation detector; and a support portion for supporting the radiation source and the radiation detector in opposed relation. The system has a structure wherein the radiation detector includes a plurality of detecting element modules arranged in an arcuate form. The detecting element module includes a base fixed to the support portion; a semiconductor layer; a high-voltage wire for supplying high voltage to the semiconductor layer; a collimator for suppressing scattered rays, and a supporting column disposed at place within a predetermined distance from the semiconductor layer.

Abstract: The present invention provides a radiation imaging apparatus capable of maintaining the quality of an image obtained even when a dose incident on a radiation detector changes suddenly. The present invention is a radiation imaging apparatus including a radiation source, a radiation detector to detect radiation emitted from the radiation source, and a cooling unit to cool the radiation detector; and is characterized in that the radiation detector has a counting circuit to output a number of photons in radiation counted per unit time as a photon counting rate, and the cooling unit controls a coolability of the radiation detector in response to the photon counting rate.

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.

Abstract: To improve performance in Photon Counting CT, pixel miniaturization, a reduction in circuit dead time, and dealing with scattered radiation and charge sharing are important. In addition, because the number of circuits increases, a reduction in power consumption of each circuit is important. Under these constraints, circuitry that deals with the scattered radiation is provided. Each pixel includes a circuit that determines whether radiation has been detected by another, adjacent pixel at the same time, and counters that count the radiation are switched on the basis of the result of the determination. On the basis of this result, counts of non-coincident events are primarily used, and coincident counts are used after being corrected, for reconstruction data.

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.

Abstract: To improve performance in Photon Counting CT, pixel miniaturization, a reduction in circuit dead time, and dealing with scattered radiation and charge sharing are important. In addition, because the number of circuits increases, a reduction in power consumption of each circuit is important. Under these constraints, circuitry that deals with the scattered radiation is provided. Each pixel includes a circuit that determines whether radiation has been detected by another, adjacent pixel at the same time, and counters that count the radiation are switched on the basis of the result of the determination. On the basis of this result, counts of non-coincident events are primarily used, and coincident counts are used after being corrected, for reconstruction data.

Abstract: When two detector panels are rotationally moved around the entire circumference of a region of interest and projection images of the region of interest are captured during the rotational movement, the respective detector panels are moved along the tangential direction of the rotational movement to a position where the union of the capturing ranges of the projection images captured by the respective detector panels covers the entire region of interest. The projection images captured by the respective detector panels are used to reconstruct a transaxial image of the region of interest.

Abstract: When two detector panels are rotationally moved around the entire circumference of a region of interest and projection images of the region of interest are captured during the rotational movement, the respective detector panels are moved along the tangential direction of the rotational movement to a position where the union of the capturing ranges of the projection images captured by the respective detector panels covers the entire region of interest. The projection images captured by the respective detector panels are used to reconstruct a transaxial image of the region of interest.

Abstract: A crucible provided with a holding section (12) for holding a raw material (20), an initial distillate recovery section (14) for recovering an initial distillate (24) when the raw material (20) held in the holding section (12) has been vaporized, a main distillate condensing section (16) for condensing a main distillate when the raw material (20) held in the holding section (12) has been vaporized, and a crystal growing section (18) for holding the main distillate (30) comprising a raw material melt (28) condensed by the main distillate condensing section (16) and producing crystals when crystals are grown from the held main distillate (30) is used as a crucible (10) for crystal growth used to grow crystals. This makes it possible to raise the efficiency of manufacturing crystals while achieving high purification of a raw material for semiconductor crystals.

Abstract: There is provided is a radiation image acquiring device which corrects a positional displacement between a collimator and a detector and obtains an image without artifacts. The device includes a detector (21) to measure a radiation; a collimator (26) including a through-hole (27) having one or more detectors (21) disposed therein and configured to limit an incident direction of the radiation; a positional displacement measuring unit configured to measure a positional displacement between the detector (21) and the collimator (26) by use of a profile of a radiation source measured by the detector (21) based on the radiation source disposed corresponding to a predetermined detector (21).

Abstract: There is provided is a radiation image acquiring device which corrects a positional displacement between a collimator and a detector and obtains an image without artifacts. The device includes a detector (21) to measure a radiation; a collimator (26) including a through-hole (27) having one or more detectors (21) disposed therein and configured to limit an incident direction of the radiation; a positional displacement measuring unit configured to measure a positional displacement between the detector (21) and the collimator (26) by use of a profile of a radiation source measured by the detector (21) based on the radiation source disposed corresponding to a predetermined detector (21).