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.

A radiation detection apparatus according to an embodiment includes a radiation detector that detects radiation; a first measurer that measures energy of the radiation from the radiation detected by the radiation detector; and a second measurer that measures the number of times that the radiation detector detects the radiation.

The present invention relates to the correction of X-ray image information, e.g. the correction of X-ray image information regarding persistent currents in X-ray detector elements. X-ray detectors may be embodied as photoconductors with ohmic contacts, which output a photo current depending on the energy and amount of photons impinging on a respective photoconductor pixel. Such photoconductors may exhibit a photoconductive gain, i.e. the measured current when irradiated by X-ray is higher than the current, which would result from impinging photons only generating electron-hole pairs. To compensate for photoconductive gain a method (50) for image correction of X-ray image information is provided, comprising receiving (52) readout information of an X-ray detector element (14), wherein the readout information is dependent on impinging X-radiation (20) generating a photo current and compensating (54) the readout information for a photoconductive gain employing compensation information.

A digital X-ray imaging system is provided. The digital X-ray imaging system includes an X-ray source and a digital X-ray detector. The digital X-ray detector includes a scintillator configured to absorb radiation emitted from the X-ray source and to emit optical photons in response to the absorbed radiation. The digital X-ray detector also includes multiple pixels, each pixel including a pinned photodiode and at least two charge-storage capacitors coupled to the pinned photodiode, wherein each pixel is configured to absorb the optical photons emitted by the scintillator and each pinned photodiode is configured to generate a photocharge in response to the absorbed optical photons. The digital X-ray detector further includes control circuitry coupled to each pixel of the multiple pixels and configured to selectively control a respective flow of the photocharge generated by the pinned photodiode to a respective charge-storage capacitor of the at least two charge-storage capacitors during integration.

A radiation imaging apparatus includes a first pixel, and a second pixel whose sensitivity for radiation is lower than sensitivity of the first pixel; and a decision unit configured to execute a reset operation of resetting charges in the pixels and a decision operation of deciding a radiation dose during irradiation to the apparatus. In the decision operation, the decision unit reads out signals from the first and second pixels at least once, and decides first and second correction values based on the signal read out from the first and second pixel respectively, and reads out signals from the first and second pixels after receiving a radiation irradiation start request, and decides the radiation dose during irradiation to the apparatus using values of the signals read out from the first and second pixels and the first and second correction values.

A radiation therapy system is configured with fast readout of X-ray images with significantly reduced image lag. A reset phase is included in the process of acquiring an X-ray image to reduce image lag in a subsequently acquired X-ray image. During the reset phase, residual charge is concurrently transferred from multiple arrays of pixel detector elements in an X-ray detector panel. As a result, image lag present in a subsequent X-ray image is minimized or otherwise reduced.

A semiconductor photomultiplier (SPM) device is described. The SPM comprises a plurality of photosensitive elements, a first electrode arranged to provide a bias voltage to the photosensitive elements, a second electrode arranged as a biasing electrode for the photosensitive elements, a plurality of quench resistive elements each associated with a corresponding photosensitive element, a plurality of output loads each having a capacitive load operably coupled to a resisitive load in a parallel configuration between first and second nodes; each first node is common to one of the photosensitive elements and the corresponding quench element; and a third electrode coupled to the second nodes of the output loads to provide an output signal from the photosensitive elements. The outputs loads fully or partially correct an overshoot of an output signal on the third electrode.

A scintillation detector, including a scintillator that emits scintillation; a semiconductor photodetector having a surface area for receiving the scintillation, wherein the surface area has a passivation layer configured to provide a peak quantum efficiency greater than 40% for a first component of the scintillation, and the semiconductor photodetector has built in gain through avalanche multiplication; a coating on the surface area, wherein the coating acts as a bandpass filter that transmits light within a range of wavelengths corresponding to the first component of the scintillation and suppresses transmission of light with wavelengths outside said range of wavelengths; and wherein the surface area, the passivation layer, and the coating are controlled to increase the temporal resolution of the semiconductor photodetector.

A discriminator (118) includes a set of comparators (120, 202.sub.1, 202.sub.3, . . . , 202.sub.N), a window width generator (124, 214, 214.sub.1, . . . , 214.sub.N), and a set of reference signal generators (122, 212.sub.1, 212.sub.2, 212.sub.3, . . . , 212.sub.N). In response to the discriminator being in a window based spectrum measurement mode, a first reference signal generator for a first comparator generates a reference signal that is supplied to the first comparator and that is added with the window width with a result of the addition supplied to the second comparator. The first comparator compares a peak height of a pulse indicative of an energy of detected radiation with the supplied reference signal and produces a first output indicating which of the peak height or the reference signal is greater. The second comparator compares the peak height with the supplied result of the addition and produces a second output indicating which of the peak height or the result of the addition is greater.

A photon counting device includes a plurality of pixels each including a photoelectric conversion element configured to convert input light to charge, and an amplifier configured to amplify the charge converted by the photoelectric conversion element and convert the charge to a voltage, an A/D converter configured to convert the voltages output from the amplifiers of the plurality of pixels to digital values; and a conversion unit configured to convert the digital value output from the A/D converter to the number of photons by referring to reference data, for each of the plurality of pixels, and the reference data is created based on a gain and an offset value for each of the plurality of pixels.