A high-energy ray detector includes a detection unit in a vacuum container. The detection unit includes a first electron multiplier, a second electron multiplier, and an electron collector. Each of the first electron multiplier and the second electron multiplier has one or more MCPs each configured to emit electrons by interaction with an incident high-energy ray (-ray, X-ray (in particular hard X-ray), or neutron ray), and multiply and output the electrons. The electron collector is transmissive for the high-energy ray. The electron collector is configured to collect the electrons multiplied and output from each of the first electron multiplier and the second electron multiplier, and output an electric pulse signal.

Various aspects include methods of compensating for issues caused by charge sharing between pixels in pixel radiation detectors. Various aspects may include measuring radiation energy spectra with circuitry capable of registering detection events occurring simultaneous or coincident in two or more pixels, adjusting energy measurements of simultaneous-multi-pixel detection events by a charge sharing correction factor, and determining a corrected energy spectrum by adding the adjusted energy measurements of simultaneous-multi-pixel detection events to energy spectra of detection events occurring in single pixels. Adjusting energy measurements of simultaneous-multi-pixel detection events may include multiplying measured energies of simultaneous-multi-pixel detection events by a factor of one plus the charge sharing correction factor.

In general, an X-ray imaging apparatus according to one embodiment includes an X-ray tube, an X-ray detector, and processing circuitry. The processing circuitry is configured to obtain correction-target data that includes component deterioration resulting from a transient response of the X-ray detector, and to output, based on the obtained correction-target and a model that outputs data in which component deterioration resulting from a transient response is reduced based on an input of data that includes component deterioration resulting from a transient response, corrected data in which the component deterioration resulting from the transient response of the X-ray detector is reduced.

Various aspects include methods of compensating for issues caused by charge sharing between pixels in pixel radiation detectors. Various aspects may include measuring radiation energy spectra with circuitry capable of registering detection events occurring simultaneous or coincident in two or more pixels, adjusting energy measurements of simultaneous-multi-pixel detection events by a charge sharing correction factor, and determining a corrected energy spectrum by adding the adjusted energy measurements of simultaneous-multi-pixel detection events to energy spectra of detection events occurring in single pixels. Adjusting energy measurements of simultaneous-multi-pixel detection events may include multiplying measured energies of simultaneous-multi-pixel detection events by a factor of one plus the charge sharing correction factor.

An SiPM sensor chip includes pixels consisting of microcells Z, each pixel being associated with an xy position x1, x2, x3, . . . , xN or y1, y2, y3, . . . yM. A plurality of pixels form a block, and the microcells are connected to output channels for a linear coding.

A PET detector array (8) comprising detector pixels acquires PET detection counts along lines of response (LORs). The counts are reconstructed to generate a reconstructed PET image (36, 46). The reconstructing is corrected for missing LORs which are missing due to dead detector pixels of the PET detector array. The correction may be by estimating counts along the missing LORs (60) by interpolating counts along LORs (66) neighboring the missing LORs. The interpolation may be iterative to handle contiguous groups of missing detector pixels. The correction may be by computing a sensitivity matrix having matrix elements corresponding to image elements (80, 82) of the reconstructed PET image. In this case, each matrix element is computed as a summation over all LORs intersecting the corresponding image element excepting the missing LORs. The computed sensitivity matrix is used in the reconstructing.

Various aspects include methods compensating for Compton scattering effects in pixel radiation detectors. Various aspects may include determining whether gamma ray detection events occurred in two or more detector pixels within an event frame, determining whether the detection events occurred in detector pixels within a threshold distance of each other in response to determining that detection events occurred in two or more detector pixels within the event frame, and recording the two or more detection events as a single detection event having an energy equal to the sum of the measured energies of the two or more detection events located in the detector pixel having a highest measured energy in response to determining that the detection events occurred in detector pixels within the threshold distance of each other.

An X-ray sensor (1) having an active detector region including a plurality of detector diodes (2) arranged on a surface region (3) of the X-ray sensor (1), a junction termination (4) surrounding the surface area (3) including the plurality of detector diodes (2), the junction termination (4) including a guard (5) arranged closest to the end of the surface region (3), a field stop (6) arranged outside the guard (2) and a number N of field limiting rings, FLRs (7) arranged between the guard (5) and the field stop (6), wherein each of the FLRs (7) are placed at positions selected so that distances between different FLRs (7) and between the guard and the first FLR lie within an effective area, the effective area being bounded by the lines =(10+1.3(n1)) m and =(5+1.05(n1)) m.

A radiation detection device (300) is used in a nuclear medicine diagnosis apparatus, and includes a plurality of scintillators (44), a semiconductor light-receiving device (SiPM), a position detection circuit (214), and a timing detection circuit (216). Each of the scintillators converts a gamma ray emitted from a subject (15) into fluorescence. The semiconductor light-receiving device is provided corresponding to each of the scintillators and converts the fluorescence converted by a corresponding one of the scintillators into an electrical signal. The position detection circuit specifies a gamma ray detection position in the scintillators based on the electrical signal from the semiconductor light-receiving device. The timing detection circuit is connected to an anode of the semiconductor light-receiving device, and specifies time information corresponding to a time of occurrence of an event in which the gamma ray is detected.

A radiation therapy system is equipped with a combined imaging system, such as an imaging system combining computed tomography (CT), spectral CT, and single photon emission tomography imaging (SPECT), for guidance of radiation beams providing radiotherapy. The system can include at least one x-ray source that emits an x-ray beam at a low energy level for imaging and/or an x-ray beam at a high energy level for radiation therapy. The system can also include at least one imager, such as a cadmium zinc telluride (CZT) or cadmium telluride (CdTe) flat-panel imager that receives x-ray beams traversing a subject from the x-ray source and gamma rays emitted by radioisotope tracers injected into the subject. Based on the guidance of the triple images (CT, spectral CT, and SPECT), a computer system can control the radiation therapeutic beam delivery to target areas, such as lesions and/or tumors.