A radiation imaging apparatus includes pixels arranged to form pixel rows and pixel columns. The pixels include first pixels and second pixels whose sensitivity to radiation is lower than the first pixels. The apparatus further includes a signal lines arranged to correspond to the pixel columns, a readout circuit configured to read out a signal from the pixels via the signal lines, and a processing unit configured to decide a correction value using signals read out from the second pixels and correct signals read out from the first pixels using the correction value. An internal structure of the readout circuit has a period. The second pixels are arranged such that there are two or more types of remainders of column numbers of pixel columns that include the second pixels divided by the period.

Provided is a pixel sensing circuit, including a signal generation sub-circuit, a reset sub-circuit, an amplification sub-circuit, and a read sub-circuit. The reset sub-circuit is configured to provide a signal of a first power supply line to a first node under control of a reset signal line. The signal generation sub-circuit is configured to detect a light signal and convert the detected light signal into an electrical signal. The amplification sub-circuit is configured to provide an amplified electrical signal to a second node according to a signal provided by a second power supply line and under control of the first node. The read sub-circuit is configured to output the amplified electrical signal to a signal read line under control of a scan signal line.

A radiation imaging apparatus includes pixels arranged to form pixel rows and pixel columns. The pixels include first pixels and second pixels whose sensitivity to radiation is lower than the first pixels. The apparatus further includes a signal lines arranged to correspond to the pixel columns, a readout circuit configured to read out a signal from the pixels via the signal lines, and a processing unit configured to decide a correction value using signals read out from the second pixels and correct signals read out from the first pixels using the correction value. An internal structure of the readout circuit has a period. The second pixels are arranged such that there are two or more types of remainders of column numbers of pixel columns that include the second pixels divided by the period.

Silicon-based photomultipliers (SiPMs) for reducing optical crosstalk effects in the SiPMs are provided. The SiPMs include macrocells. Each macrocell includes microcells, coupled in parallel, and a reading circuit coupled to an output of each macrocell. The microcells are arranged in the SiPM so that adjacent microcells belong to different macrocells. When a microcell performs a detection, the reading circuit of each macrocell having one or more microcells adjacent to the microcell that performed the detection is configured to disable its output signal during a predefined period of time. PET devices or systems and methods for reducing crosstalk effects are also provided.

A radiation imaging apparatus is provided. The apparatus includes a substrate in which conversion elements are arranged and which transmits light beams, a first scintillator arranged on a first surface side of the substrate, and a second scintillator arranged on a second surface side opposite to the first surface. The conversion elements include first conversion elements and second conversion elements. The first conversion elements are arranged so as to receive light beams from the first scintillator and the second scintillator. A light-shielding layer is arranged between the first scintillator and each of the second conversion elements so as to set light amounts of the second conversion elements from the first scintillator smaller than those of the first conversion elements from the first scintillator, and the second conversion elements are arranged to receive a light beam from the second scintillator.

A radiation imaging apparatus comprises at least one first detection element including a first conversion element configured to convert radiation into an electrical signal and a first switch configured to connect an output from the first conversion element to a first signal line, at least one second detection element including a second conversion element configured to convert radiation into an electrical signal and a second switch configured to connect an output from the second conversion element to a second signal line, a readout unit configured to read out signals appearing on the first signal line and the second signal line, and a signal processing circuit configured to process a signal read out from the readout unit. A sensitivity of the first conversion element for the radiation is set to be different from a sensitivity of the second conversion element for the radiation.

According to one embodiment, a radiation detector includes a base body, a first radiation detection element, and a second radiation detection element. The base body includes a first surface. The first surface includes first and second partial regions. A first direction from the first partial region toward the second partial region is along the first surface. The first radiation detection element is fixable to the first partial region. The second radiation detection element includes a first detecting part fixable to the second partial region. The first detecting part includes first and second end portions. A second direction from the first end portion toward the second end portion crosses the first surface. The second end portion is between the first end portion and the second partial region in the second direction. The first radiation detection element does not overlap the first end portion in the first direction.

According to one embodiment, a radiation detector includes a first layer, a first light-emitting part, a detecting part, a detection circuit, and a first drive circuit. The first layer includes a first organic material. The first light-emitting part includes a first organic light-emitting layer. The detecting part is provided between the first layer and the first light-emitting part. The detecting part includes an organic photoelectric conversion layer and is configured to generate an electrical signal corresponding to radiation incident on the first layer. The detection circuit is configured to output a detection signal based on the electrical signal. The first drive circuit is configured to supply a first drive signal to the first light-emitting part based on the detection signal.

[Object] To achieve a radiation detector capable of suppressing variation in the amount of radiation detected. [Solution] A first gate electrode (52) is connected to a light receiving device, and a second gate electrode (53) is configured to have the same potential as that of the first gate electrode (52).

According to one embodiment, a photoelectric conversion element includes a first conductive layer, a second conductive layer, and an intermediate layer provided between the first conductive layer and the second conductive layer. The intermediate layer includes a first semiconductor region and a second semiconductor region. The first semiconductor region is of an n-type, and the second semiconductor region is of a p-type. The first semiconductor region includes at least one selected from the group consisting of fullerene and a fullerene derivative. The second semiconductor region includes at least one selected from the group consisting of quinacridone and a quinacridone derivative. A ratio of a weight of the second semiconductor region per unit volume to a weight of the first semiconductor region per unit volume in the intermediate layer is greater than 5.