Abstract: A light detector includes a semiconductor light detection element having a plurality of light detection units disposed two-dimensionally and readout wirings and a plurality of metalenses disposed on a surface of the semiconductor light detection element. Each of the plurality of light detection units has an avalanche photodiode including a first semiconductor region and a second semiconductor region forming a PN junction with the first semiconductor region, and a quenching resistor including one end electrically connected to the second semiconductor region and another end electrically connected to the readout wiring. The plurality of metalenses are disposed two-dimensionally to overlap the plurality of light detection units, and converge light such that a convergence spot is located at a position which is within the first semiconductor region and which is separated by a predetermined distance from a boundary between the first semiconductor region and the second semiconductor region.

Abstract: Disclosed is a gas sensor element having: a solid electrolyte body containing oxygen-ion conductive ZrO2; a detection electrode disposed on the solid electrolyte body to be exposed to a gas under measurement; and a reference electrode disposed on the solid electrolyte body to be exposed to a reference gas. In the gas sensor element, the detection electrode contains Pt and ZrO2; the detection electrode has a thickness of 3 to 10 ?m; the amount of ZrO2 contained relative to Pt in the detection electrode is 12 to 18 wt %; the detection electrode has a porosity of 5% or lower; and, in a particle size distribution graph of ZrO2 particles in the detection electrode, a cumulative value of peaks appearing in a range of 0.025 ?m to 0.200 ?m is 60 to 75%, and a cumulative value of peaks appearing in a range of 1.000 ?m to 3.162 ?m is 2 to 7%.

Abstract: A radiation detector of one embodiment includes: a scintillator configured to generate first scintillation light having a first peak wavelength and second scintillation light having a second peak wavelength in response to radiation incidence; a photodetection unit configured to detect the scintillation light generated by the scintillator; and a filter layer disposed between the scintillator and the photodetection unit and configured to selectively block the first scintillation light. The filter layer has a metasurface structure.

Abstract: A photodetector includes N photodetection pixels arranged one-dimensionally or two-dimensionally and each for generating a detection signal in response to incidence of light, and a single output terminal for outputting the detection signal generated in each of the N photodetection pixels. Each of the N photodetection pixels includes an avalanche photodiode operating in Geiger mode, and a quenching resistor connected in series to the avalanche photodiode, and the N photodetection pixels are configured to output detection signals having time waveforms different from each other.

Abstract: A radiation detection device includes a scintillator, a photodetector for detecting scintillation light from the scintillator and outputting a detection signal, a first comparator for comparing the detection signal with a first threshold voltage V1 and outputting a signal having a first time width T1, a first time width measurement device for measuring the first time width T1, a second comparator for comparing the detection signal with a second threshold voltage V2 and outputting a signal having a second time width T2, a second time width measurement device for measuring the second time width T2, and an analysis unit for obtaining a time constant ? indicating a time waveform of the detection signal based on the first and second time widths T1 and T2.

Abstract: Disclosed is a gas sensor element having: a solid electrolyte body containing oxygen-ion conductive ZrO2; a detection electrode disposed on the solid electrolyte body to be exposed to a gas under measurement; and a reference electrode disposed on the solid electrolyte body to be exposed to a reference gas. In the gas sensor element, the detection electrode contains Pt and ZrO2; the detection electrode has a thickness of 3 to 10 ?m; the amount of ZrO2 contained relative to Pt in the detection electrode is 12 to 18 wt %; the detection electrode has a porosity of 5% or lower; and, in a particle size distribution graph of ZrO2 particles in the detection electrode, a cumulative value of peaks appearing in a range of 0.025 ?m to 0.200 ?m is 60 to 75%, and a cumulative value of peaks appearing in a range of 1.000 ?m to 3.162 ?m is 2 to 7%.

Abstract: A gamma ray detector is a detector detecting gamma rays and includes a photomultiplier tube having an entrance window and a photoelectric surface. The entrance window is a Cherenkov radiator. The photoelectric surface is formed on a vacuum side of the entrance window via an intermediate layer. The thickness of the intermediate layer is equal to or less than the wavelength of Cherenkov light emitted by an interaction of the gamma rays with the entrance window.

Abstract: A photodetector includes N photodetection pixels arranged one-dimensionally or two-dimensionally and each for generating a detection signal in response to incidence of light, and a single output terminal for outputting the detection signal generated in each of the N photodetection pixels. Each of the N photodetection pixels includes an avalanche photodiode operating in Geiger mode, and a quenching resistor connected in series to the avalanche photodiode, and the N photodetection pixels are configured to output detection signals having time waveforms different from each other.

Abstract: A radiation detection device includes a scintillator, a photodetector for detecting scintillation light from the scintillator and outputting a detection signal, a first comparator for comparing the detection signal with a first threshold voltage V1 and outputting a signal having a first time width T1, a first time width measurement device for measuring the first time width T1, a second comparator for comparing the detection signal with a second threshold voltage V2 and outputting a signal having a second time width T2, a second time width measurement device for measuring the second time width T2, and an analysis unit for obtaining a time constant ? indicating a time waveform of the detection signal based on the first and second time widths T1 and T2.

Abstract: 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.

Abstract: A radiation position detector includes a radiator including a medium that generates light in a first wavelength region and light in a second wavelength region by interacting with incident radiation, a first photodetector that includes a plurality of first two-dimensionally arranged pixels and detects the light in the first wavelength region, and a second photodetector that includes a plurality of second two-dimensionally arranged pixels and detects the light in the second wavelength region.

Abstract: A radiation position detector includes a radiator including a medium that generates Cherenkov light by interacting with an incident radiation, a photodetector including a plurality of two-dimensionally arrayed pixels, the plurality of pixels being disposed to correspond to a predetermined surface of the radiator, and a control unit that acquires position information and time information of the plurality of pixels which have detected the Cherenkov light on the basis of a signal output from the photodetector, and obtains a position of a generation place of the Cherenkov light in the radiator on the basis of the acquired position information and the acquired time information, and a propagation locus of the Cherenkov light in the radiator.

Abstract: A charged particle track detector includes a radiator including a medium that generates Cherenkov light by interacting with incident charged particles, a light detection unit in which a plurality of two-dimensionally arrayed pixels are disposed to correspond to a predetermined surface of the radiator, and a control unit configured to acquire position information and time information of the plurality of pixels that have detected the Cherenkov light based on a signal output from the light detection unit, and configured to obtain a track of the charged particles based on the acquired position information and the acquired time information, and a propagation locus of the Cherenkov light in the radiator.

Abstract: 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.

Abstract: A gamma ray detector is a detector detecting gamma rays and includes a photomultiplier tube having an entrance window and a photoelectric surface. The entrance window is a Cherenkov radiator. The photoelectric surface is formed on a vacuum side of the entrance window via an intermediate layer. The thickness of the intermediate layer is equal to or less than the wavelength of Cherenkov light emitted by an interaction of the gamma rays with the entrance window.

Abstract: A radiation position detector includes a radiator including a medium that generates light in a first wavelength region and light in a second wavelength region by interacting with incident radiation, a first photodetector that includes a plurality of first two-dimensionally arranged pixels and detects the light in the first wavelength region, and a second photodetector that includes a plurality of second two-dimensionally arranged pixels and detects the light in the second wavelength region.

Abstract: A charged particle track detector includes a radiator including a medium that generates Cherenkov light by interacting with incident charged particles, a light detection unit in which a plurality of two-dimensionally arrayed pixels are disposed to correspond to a predetermined surface of the radiator, and a control unit configured to acquire position information and time information of the plurality of pixels that have detected the Cherenkov light based on a signal output from the light detection unit, and configured to obtain a track of the charged particles based on the acquired position information and the acquired time information, and a propagation locus of the Cherenkov light in the radiator.

Abstract: A scintillator array including a plurality of scintillators, an optical detector array corresponding to the scintillators, an AD conversion unit configured to convert an analog signal output from each optical detector into digital data, and a position detection processing unit configured to specify a position of the scintillator on which the radiation is incident are provided. If there are two different pieces of digital data at the same time, the position detection processing unit determines that radiation is incident on two scintillators when energy value data of the two pieces of digital data is greater than an energy value of a Compton edge and specifies the address of the scintillator on which the radiation is incident by comparing the energy values of the two pieces of digital data when at least one of the two energy values is less than the energy value of the Compton edge.

Abstract: A scintillator array including a plurality of scintillators, an optical detector array corresponding to the scintillators, an AD conversion unit configured to convert an analog signal output from each optical detector into digital data, and a position detection processing unit configured to specify a position of the scintillator on which the radiation is incident are provided. If there are two different pieces of digital data at the same time, the position detection processing unit determines that radiation is incident on two scintillators when energy value data of the two pieces of digital data is greater than an energy value of a Compton edge and specifies the address of the scintillator on which the radiation is incident by comparing the energy values of the two pieces of digital data when at least one of the two energy values is less than the energy value of the Compton edge.