Abstract: According to an embodiment, a circuit includes a shunt and a controller. The shunt shunts input current into a plurality of current paths. The controller controls a gain of current inputted to the shunt by combining the current that is shunted into the current paths by the shunt in combination corresponding to a first signal from the outside or changing a shunt ratio with which the shunt shunts the current into the current paths corresponding to the first signal.

Abstract: A waveform shaping filter according to an embodiment includes at least one filter stage and a control circuit. The filter stage includes a differentiation signal generation circuit, a proportional signal generation circuit, and an adder circuit. The differentiation signal generation circuit generates a differentiation signal obtained by amplifying a differentiation component of an input signal. The proportional signal generation circuit generates a proportional signal obtained by amplifying the input signal. The adder circuit outputs an output signal obtained by adding the proportional signal and the differentiation signal. The control circuit compares the output signal and a first detection level, detects at least one of an overshoot and an undershoot of the output signal, and controls a time constant of the filter stage, based on a detection result.

Abstract: In one embodiment, a differential amplifier circuit includes a first input terminal, a second input terminal, a first transistor, a second transistor, a third transistor, a current source, a first output terminal, a second output terminal, a first passive element, and a second passive element. The first (second) transistor has a control terminal connected to the first (second) input terminal. The third transistor has a control terminal. The control terminal is applied predetermined bias voltage. The current source is connected to a first terminal in each of the first transistor, second transistor, and third transistor. The first (second) output terminal is connected to a second terminal of the first (second) transistor. The first (second) passive element is connected between the first (second) input terminal and the first (second) output terminal.

Abstract: 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.

Abstract: An integration circuit according to one embodiment includes a first capacitance element, a capacitance circuit, a comparison circuit, a memory circuit and an operation circuit. The first capacitance element receives a current signal. The capacitance circuit includes a first switch and a second capacitance element, and is connected in parallel to the first capacitance element. The second capacitance element receives a current signal via the first switch. The comparison circuit compares a voltage of the first capacitance element with a reference voltage to obtain a comparison result. The memory circuit stores the comparison result, and opens or closes the first switch based on the comparison result. The operation circuit outputs a residual signal based on a difference between the integrated value obtained by the first capacitance element and the second capacitance element and a value based on the comparison result.

Abstract: According to an embodiment, a photodetector includes a plurality of photoelectric transducers, a plurality of resistors, and a plurality of resetting sections. Each of the photoelectric transducers is configured to output a detection signal resulting from conversion of received light into an electric charge. Each of the resistors is connected in series with an output end of a corresponding photoelectric transducer at one end of the resistor. Each of the resetting sections is connected in parallel with a corresponding resistor and configured to bring the output end of the corresponding photoelectric transducer to a reset level in response to the detection signal.

Abstract: According to an embodiment, a photon detecting element includes one or more avalanche photodiodes and a circuit. The circuit is connected between cathodes of the one or more avalanche photodiodes and an external power source. The circuit is configured in which a first temperature coefficient representing variation of a setting potential with respect to temperature variation when constant-current driving is performed so that electrical potential of the cathodes becomes equal to the setting potential is substantially the same as a second temperature coefficient representing variation of breakdown voltage of the one or more avalanche photodiodes with respect to temperature variation.

Abstract: According to an embodiment, a signal processing device includes a first integrator, a second integrator, a switcher, and a calculator. The first integrator is configured to integrate a current represented by a reference waveform equivalent to a normal waveform in a case of no pileup phenomenon regarding the current to calculate a first electrical charge. The second integrator is configured to integrate a current output from a photoelectric converter to calculate a second electrical charge. The switcher is configured to, when a pileup phenomenon has occurred, perform switching either to a state in which the first and second electrical charges are output or to a state in which the first electrical charge and a reference charge are output. The calculator is configured to calculate a first difference charge between the first and second electrical charges, and calculate a second difference charge between the first electrical charge and the reference charge.

Abstract: A power supply stabilizing circuit includes a diode having a cathode connected to an output terminal of a direct current power circuit configured to generate a direct current voltage and to supply the voltage therefrom to a load circuit, and a capacitor connected to an anode of the diode. The power supply stabilizing circuit may further include a transistor having a first terminal connected to the output terminal of the direct current power circuit, a second terminal connected to a connection node between the diode and the capacitor, and a switching electrode connected to the connection node.

Abstract: According to an embodiment, a photon counting CT apparatus includes a scintillator, a photodiode array, a holder, a divider, and an image generator. The scintillator is configured to convert X-rays into light. The array includes first and second pixels. The first pixel includes a photodiode in a first range receiving the light emitted from the scintillator. The photodiode outputs an electrical signal based on the light. The second pixel includes a photodiode in a second range different from the first range. The holder is circuitry configured to hold a value of an electrical signal output by the second pixel. The divider circuitry is configured to count the number of photons of light incident on the first pixel by dividing an integrated value of electrical signals output by the first pixel by the held value. The image generator is circuitry configured to reconstruct an image based on the counted number.

Abstract: There is provided an electromagnetic wave signal processor configured to process an input pulse signal corresponding to an electromagnetic wave, comprising a signal processing unit including: a peak detecting circuit to detect peak values of each amplitude of the input pulse signal; an AD converter to convert the peak values into digital signals; a memory device comprising memory cells each having an address assigned in accordance with each of values capable of being taken by the digital signals of the peak values, and being able to have any one of a plurality of internal states representing detection frequencies of the peak values; and a writing circuit to change the internal state in the memory cell that has the address corresponding to the value of each digital signal converted by the AD converter, so as to increment the detection frequency represented by the internal state.

Abstract: A photodetector according to an embodiment includes: a photodetector element unit including a first cell array including a plurality of first cells arranged in an array and a second sell array including a plurality of second cells arranged in an array, each of the first and second cells including a photoelectric conversion element, the second cell array being arranged to be adjacent to the first cell array; a first pulse height analyzer unit analyzing a pulse height of an electrical signal outputted from the first cell array; a second pulse height analyzer unit analyzing a pulse height of an electrical signal outputted from the second cell array; and a signal processing unit determining non-uniformity of a distribution of photons entering the first and second cell arrays using an output signal of the first pulse height analyzer unit and an output signal of the second pulse height analyzer unit.

Abstract: An integration circuit according to one embodiment includes a first capacitance element, a capacitance circuit, a comparison circuit, a memory circuit and an operation circuit. The first capacitance element receives a current signal. The capacitance circuit includes a first switch and a second capacitance element, and is connected in parallel to the first capacitance element. The second capacitance element receives a current signal via the first switch. The comparison circuit compares a voltage of the first capacitance element with a reference voltage to obtain a comparison result. The memory circuit stores the comparison result, and opens or closes the first switch based on the comparison result. The operation circuit outputs a residual signal based on a difference between the integrated value obtained by the first capacitance element and the second capacitance element and a value based on the comparison result.

Abstract: According to an embodiment, a photodetector includes a plurality of photoelectric transducers, a plurality of resistors, and a plurality of resetting sections. Each of the photoelectric transducers is configured to output a detection signal resulting from, conversion of received light into an electric charge. Each of the resistors is connected in series with an output end of a corresponding photoelectric transducer at one end of the resistor. Each of the resetting sections is connected in parallel with a corresponding resistor and configured to bring the output end of the corresponding photoelectric transducer to a reset level in response to the detection signal.

Abstract: According to an embodiment, a signal processing device includes an integrator, a first analog-to-digital converter, and a histogram creator. The integrator is configured to integrate an electrical charge corresponding to electromagnetic waves. The first analog-to-digital converter is configured to perform an analog-to-digital conversion operation that generates digital data of the electrical charge using an integration output from the integrator, on a parallel with an integration operation performed by the integrator. The histogram creator is configured to create a histogram that represents an energy distribution of the electromagnetic waves, from the digital data generated by the first analog-to-digital converter.

Abstract: A current detection circuit according to one embodiment includes a low-pass filter, a voltage-to-current converter circuit, and a comparator. The low-pass filter has a first terminal connected to a signal input terminal to which a signal current is input. The voltage-to-current converter circuit has a first terminal connected to a second terminal of the low-pass filter and has a second terminal connected to the signal input terminal. The comparator has a first input terminal and a second input terminal and outputs a signal according to a difference between a signal input through the first input terminal and a signal input through the second input terminal, the first input terminal being connected to the second terminal of the low-pass filter, and the second input terminal being connected to the second terminal of the voltage-to-current converter circuit.

Abstract: A method suitable to reprocess a semiconductor substrate is provided. A semiconductor substrate in which a projection including a damaged semiconductor region and an insulating layer is provided in a peripheral portion of the semiconductor substrate is subjected to etching treatment for removing the insulating layer and to etching treatment for removing the damaged semiconductor region selectively with a non-damaged semiconductor region left using a mixed solution including nitric acid, a substance dissolving a semiconductor material included in the semiconductor substrate and oxidized by the nitric acid, a substance controlling a speed of oxidation of the semiconductor material and a speed of dissolution of the oxidized semiconductor material, and nitrous acid, in which the concentration of the nitrous acid is higher than or equal to 10 mg/l and lower than or equal to 1000 mg/l. Through these steps, the semiconductor substrate is reprocessed.

Abstract: A photodetector according to an embodiment includes: a photodetector element unit including a first cell array including a plurality of first cells arranged in an array and a second cell array including a plurality of second cells arranged in an array, each of the first and second cells including a photoelectric conversion element, the second cell array being arranged to be adjacent to the first cell array; a first pulse height analyzer unit analyzing a pulse height of an electrical signal outputted from the first cell array; a second pulse height analyzer unit analyzing a pulse height of an electrical signal outputted from the second cell array; and a signal processing unit determining non-uniformity of a distribution of photons entering the first and second cell arrays using an output signal of the first pulse height analyzer unit and an output signal of the second pulse height analyzer unit.

Abstract: A fuel cell has a fuel cell main body, a fuel supply unit, a voltage sensor, a supply speed determining unit, a fuel supply control unit, and a connecting unit. The voltage sensor measures the open-circuit voltage of the fuel cell main body. The supply speed determining unit determines the fuel supply speed of the fuel supply unit, on the basis of the results obtained from the measurement performed by the voltage sensor, in the case where the voltage measured by the voltage sensor is smaller than a predetermined value. The fuel supply control unit controls, on the basis of the supply speed thus determined, the fuel supply from the fuel supply unit. The connecting unit connects a load to the fuel cell main body, in the case where the voltage measured by the voltage sensor is larger than the predetermined value.

Abstract: There is provided a single to differential conversion circuit including: a divider circuit, first and second bias current generators, first and second output terminals and a current generating circuit. The divider circuit receives an input current including a DC component and an AC component and divides the input current to generate a first current and a second current. The first bias current generator generates a first bias current. The first output terminal outputs a first output current depending on a difference between the first current and the first bias current. The current generating circuit generates a third current which has a sign opposite to the second current on the basis of the second current. The second bias current generator generates a second bias current. The second output terminal outputs a second output current depending on a difference between the third current and the second bias current.