A waveform shaping filter according to one embodiment includes a first resistor, a first transistor, a first capacitor, and a first amplifier. The first resistor includes one end to which a signal current is input and the other end. The first transistor includes a first terminal connected to the other end of the first resistor, a second terminal, and a control terminal. The first capacitor includes one end connected to the other end of the first resistor and the other end. The first amplifier includes an input terminal connected to the one end of the first resistor and an output terminal connected to the control terminal of the first transistor.

A waveform shaping filter according to one embodiment includes a first resistor, a first transistor, a first capacitor, and a first amplifier. The first resistor includes one end to which a signal current is input and the other end. The first transistor includes a first terminal connected to the other end of the first resistor, a second terminal, and a control terminal. The first capacitor includes one end connected to the other end of the first resistor and the other end. The first amplifier includes an input terminal connected to the one end of the first resistor and an output terminal connected to the control terminal of the first transistor.

A photon-counting X-ray computed tomography (CT) apparatus of an embodiment includes photon-counting CT detection circuitry, integral CT detection circuitry, switching circuitry, and a feedback capacitance. Photon-counting CT detection circuitry outputs count values for respective energy bins, based on voltage pulses output from a feedback capacitance with electric charges output from an X-ray detection element configured to detect incident X-rays. Integral CT detection circuitry outputs an integral value, based on the voltage pulses output from the feedback capacitance with the electric charges output from the X-ray detection element. Switching circuitry switches between a case of transmitting the electric charges output from the X-ray detection element to the photon-counting CT detection circuitry and a case of transmitting the electric charges output from the X-ray detection element to the integral CT detection circuitry. The feedback capacitance is connected with the photon-counting CT detection circuitry and the integral CT detection circuitry in parallel.

A photon-counting X-ray computed tomography (CT) apparatus of an embodiment includes photon-counting CT detection circuitry, integral CT detection circuitry, switching circuitry, and a feedback capacitance. Photon-counting CT detection circuitry outputs count values for respective energy bins, based on voltage pulses output from a feedback capacitance with electric charges output from an X-ray detection element configured to detect incident X-rays. Integral CT detection circuitry outputs an integral value, based on the voltage pulses output from the feedback capacitance with the electric charges output from the X-ray detection element. Switching circuitry switches between a case of transmitting the electric charges output from the X-ray detection element to the photon-counting CT detection circuitry and a case of transmitting the electric charges output from the X-ray detection element to the integral CT detection circuitry. The feedback capacitance is connected with the photon-counting CT detection circuitry and the integral CT detection circuitry in parallel.

A semiconductor light detection element includes a plurality of avalanche photodiodes operating in Geiger mode and formed in a semiconductor substrate, quenching resistors connected in series to the respective avalanche photodiodes and arranged on a first principal surface side of the semiconductor substrate, and a plurality of through-hole electrodes electrically connected to the quenching resistors and formed so as to penetrate the semiconductor substrate from the first principal surface side to a second principal surface side. A mounting substrate includes a plurality of electrodes arranged corresponding to the respective through-hole electrodes on a third principal surface side. The through-hole electrodes and the electrodes are electrically connected through bump electrodes, and a side surface of the semiconductor substrate and a side surface of a glass substrate are flush with each other.

A semiconductor light detection element includes a plurality of avalanche photodiodes operating in Geiger mode and formed in a semiconductor substrate, quenching resistors connected in series to the respective avalanche photodiodes and arranged on a first principal surface side of the semiconductor substrate, and a plurality of through-hole electrodes electrically connected to the quenching resistors and formed so as to penetrate the semiconductor substrate from the first principal surface side to a second principal surface side. A mounting substrate includes a plurality of electrodes arranged corresponding to the respective through-hole electrodes on a third principal surface side. The through-hole electrodes and the electrodes are electrically connected through bump electrodes, and a side surface of the semiconductor substrate and a side surface of a glass substrate are flush with each other.

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 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 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.