JPWO2017187971A1 - Radiation detection apparatus and signal processing apparatus for radiation detection - Google Patents

Abstract

The present invention reduces adverse effects due to crosstalk of reset signals and suppresses an increase in dead time, and outputs a plurality of radiation detection units 2 that output charges generated by the incidence of radiation. A plurality of conversion units 3 provided corresponding to the plurality of radiation detection units 2 and converting the integrated amount of generated charges into an integrated signal corresponding to the integrated amount, and processing the integrated signals from the plurality of conversion units 3 Then, the signal processing unit 4 that generates radiation information, the reset control unit 5 that outputs a reset signal to the conversion unit 3 to reset the electric charge accumulated in the conversion unit 3, and the integrated signals from the plurality of conversion units or A reset information acquisition unit 6 that acquires reset information indicating that any of the conversion units 3 has been reset using the obtained signal, the signal processing unit 4 based on the reset information, From the integrated signal or signals obtained therefrom from another conversion unit 3B is a set transform unit 3A, having a noise removal unit 44 for removing noise due to the reset (46).

Description

  The present invention relates to a radiation detection apparatus and a signal processing apparatus used for the radiation detection apparatus.

  As a conventional radiation detection apparatus, as shown in Patent Documents 1 and 2, the accumulated amount of charges output from a radiation detection unit having a semiconductor radiation detection element such as an SDD (Silicon Drift Detector) is used as a CSA (Charge Sensitive Amplifier). ) Or the like is converted into an integration signal (for example, a voltage signal) corresponding to the integration amount and input to a pulse processor such as a DPP (Digital Pulse Processor). This pulse processor shapes the integrated signal into a pulse signal having a trapezoidal waveform, for example. The peak value of this pulse signal corresponds to the energy of radiation. A radiation spectrum can be obtained by counting this pulse signal for each wave height with a counter such as MCA (Multi Channel Analyzer).

  Here, the conversion unit such as CSA has a capacitor for accumulating charges output from the radiation detection unit, and a switch for resetting (discharging) the charges accumulated in the capacitor. Then, it is necessary to input a reset signal from the outside to the switch at a predetermined timing before the capacitor charge is saturated and to turn on the switch for a predetermined time to reset the capacitor charge. In the case of a radiation detection unit having a plurality of output channels, a conversion unit is provided for each output channel, and thus it is necessary to reset each conversion unit.

Japanese Patent Laid-Open No. 10-186041 JP-A-11-109039

  Here, as a method of resetting the capacitors of the plurality of conversion units, (1) an asynchronous reset method in which each capacitor is individually reset when the accumulated charge (voltage) of each capacitor reaches a predetermined value; 2) When the accumulated charge (voltage) of any capacitor reaches a predetermined value, the capacitors of all the conversion units are reset, and all the conversion units do not take in the signal from the radiation detection unit during the reset period. A synchronous reset method is considered.

  However, in the asynchronous reset method, the crosstalk due to the reset pulse is added as noise to the output voltage of the conversion unit that is not reset, and is processed as a pseudo radiation input pulse. As a result, the resolution of the radiation spectrum is lowered, or a pseudo spectrum is formed in a low energy region.

  Further, in the synchronous reset method, every time one of the capacitors is reset, all the conversion units do not take in the signal from the radiation detection unit, and the dead time is increased. Then, in the mapping, the radiation input process cannot be performed simultaneously in all the conversion units, and the count rate is extremely reduced in the pixels corresponding to the reset period, resulting in missing dots.

  Accordingly, the present invention has been made to solve the above-mentioned problems all at once, and its main problem is to reduce the adverse effects of reset signal crosstalk and to suppress an increase in dead time. Is.

  That is, a radiation detection apparatus according to the present invention is provided corresponding to a plurality of radiation detection units that output charges generated by incidence of radiation and the plurality of radiation detection units, and the integrated amount of the generated charges is calculated. A plurality of converters for converting into integrated signals according to the integrated amount, a signal processor for processing integrated signals from the plurality of converters to generate radiation information, and outputting a reset signal to the converter Reset information indicating that any of the conversion units has been reset using a reset control unit that resets the electric charge accumulated in the conversion unit, and an integration signal from the plurality of conversion units or a signal obtained therefrom. A reset information acquisition unit to acquire, and the signal processing unit, based on the reset information, an integrated signal from a conversion unit different from the reset conversion unit or a signal obtained therefrom. From characterized as having a noise removing unit for removing noise due to the reset.

  According to this radiation detection apparatus, using the integrated signals from the plurality of conversion units or signals obtained therefrom, reset information indicating that any conversion unit has been reset is acquired, and the converted conversion unit is reset. Since the noise caused by reset is removed from the integrated signal from the converter different from that or the signal obtained from it, the reset signal crosstalk reduces the resolution of the radiation spectrum or forms a pseudo spectrum in the low energy region Can be prevented. In addition, the present invention does not have a configuration in which all the conversion units do not take in the signal from the radiation detection unit every time one of the conversion units is reset as in the synchronous reset method, thereby suppressing an increase in dead time. be able to. Further, since it is detected that any of the conversion units has been reset using the integrated signal from the conversion unit or a signal obtained therefrom, there is no need to acquire reset information from the reset control unit.

The reset information acquisition unit acquires a reset start point by a change in the integration signal or a signal obtained therefrom, and the noise removal unit is an integration signal from a conversion unit different from the converted conversion unit or It is desirable to remove a signal of a predetermined period determined based on the reset start time from the signal obtained therefrom.
With this configuration, it is only necessary to acquire the reset start time, and it is only necessary to uniformly remove the integration signal of a predetermined period set in advance based on the reset start time or a signal obtained therefrom. Becomes easy.

The reset information acquisition unit acquires a reset end point based on a change in the integration signal or a signal obtained therefrom, and the noise removal unit integrates from a conversion unit different from the reset conversion unit. It is desirable that a signal of a predetermined period determined based on the reset end point is removed from the signal or a signal obtained therefrom.
With this configuration, it is only necessary to acquire the reset end point, and it is sufficient to uniformly remove the integration signal for a predetermined period set in advance based on the reset end point or the signal obtained therefrom. Becomes easy. In addition, by acquiring the reset end point, it is possible to prevent the voltage signal after the reset end point from being removed wastefully.

  As a specific embodiment of the signal processing unit, the signal processing unit includes a waveform shaping unit that shapes the integrated signal from the conversion unit into a pulse signal, and a peak value of the pulse signal shaped by the waveform shaping unit. And a count unit that counts the peak value obtained by the peak detection unit according to the peak height, and the noise removing unit is obtained by the peak detection unit based on the reset information. It is desirable to remove noise from the obtained peak value.

  As another embodiment of the signal processing unit, the signal processing unit is configured to delay the integrated signal from the conversion unit for a predetermined time, and shape the integrated signal delayed by the delay unit into a pulse signal. A waveform shaping unit, a pulse height detection unit that detects a peak value of the pulse signal shaped by the waveform shaping unit, and a count unit that counts the peak value obtained by the pulse height detection unit for each pulse height, The noise removing unit may remove crosstalk noise from the integrated signal delayed by the delay unit based on the reset information.

The plurality of radiation detection units are preferably configured by dividing the surface of the semiconductor block into a plurality of radiation detection regions and providing a collection electrode in each region.
In this configuration, a plurality of collecting electrodes are provided in the semiconductor block, and the crosstalk noise of the reset pulse is easily applied. Therefore, the effect of the present invention can be made more remarkable. In addition, by dividing the semiconductor block into multiple radiation detection regions, the area per each collection electrode is reduced, and the bias voltage required to create the same drift electric field can be reduced, so that the leakage current can be reduced. , The S / N ratio of the signal is improved.

  The radiation detection signal processing apparatus according to the present invention is provided corresponding to a plurality of radiation detection units that output charges generated by incidence of radiation, and the accumulated amount of the generated charges is used as the accumulated amount. A plurality of converters for converting into corresponding integrated signals, a signal processor for processing the integrated signals from the plurality of converters to generate radiation information, and outputting a reset signal to the converter and storing it in the converter Reset information acquisition for acquiring reset information indicating that any of the conversion units has been reset, using a reset control unit for resetting the generated charge and an integration signal from the plurality of conversion units or a signal obtained therefrom And the signal processing unit includes a noise removing unit that removes noise caused by the reset based on the reset information.

  According to the present invention configured as described above, reset information indicating that any of the conversion units has been reset is acquired and reset using the integrated signals from the plurality of conversion units or signals obtained therefrom. Since the noise caused by reset is removed from the integrated signal from the conversion unit different from the conversion unit or the signal obtained from it, the adverse effect due to crosstalk of the reset signal is reduced and the dead time is increased. Can be suppressed.

It is a schematic diagram which shows the structure of the X-ray detection apparatus of this embodiment. It is a schematic diagram which shows the circuit connected to one semiconductor detection part of the embodiment. It is a schematic diagram which shows the structure of the X-ray detection part of the embodiment. It is a functional block diagram which shows the reset information acquisition part of the embodiment. It is a figure which shows the fast type | system | group output waveform obtained from the voltage signal of each conversion part and the voltage signal of a reset conversion part in the reset period of the embodiment. It is a schematic diagram which shows the circuit connected to one semiconductor detection part of deformation | transformation embodiment. It is a functional block diagram which shows the reset information acquisition part of deformation | transformation embodiment. It is a figure which shows the outline | summary of the signal processing of deformation | transformation embodiment.

DESCRIPTION OF SYMBOLS 100 ... X-ray detection apparatus 2 ... X-ray detection part 3 ... Conversion part 4 ... Signal processing part 44 ... Noise removal part 46 ... Noise removal part 5 ... Reset control part 6 ... Reset information acquisition unit

  An X-ray detection apparatus which is an aspect of the radiation detection apparatus according to the present invention will be described below with reference to the drawings.

  As shown in FIGS. 1 and 2, the X-ray detection apparatus 100 of the present embodiment includes a plurality of X-ray detection units 2 that output charges generated by the incidence of X-rays, and a plurality of X-ray detection units 2. A plurality of conversion units 3 that are provided corresponding to each of the plurality of conversion units 3 to convert the integrated amount of generated charges into voltage signals that are integration signals corresponding to the integration amount, and process the voltage signals from the plurality of conversion units 3 And a signal processing unit 4 for generating X-ray information.

  The plurality of X-ray detectors 2 are silicon drift detectors (SDD (Silicon Drift Detector)). The silicon drift detector collects charges generated at the collecting electrode in the central portion by a concentric electrode structure. In this silicon drift detector, incident X-rays are absorbed by the depletion layer, and the number of electron-hole pairs proportional to the energy of the incident X-rays in the depletion layer is generated. The generated electrons follow the potential gradient in the silicon drift detector, and the generated electrons flow to the collecting electrode (anode). Thereby, the silicon drift detector outputs a charge proportional to the energy of the incident X-ray.

  Specifically, as shown in FIG. 3, the plurality of X-ray detection units 2, the surface of a single semiconductor block 200 is divided into a plurality of X-ray detection regions R1 to R4 and collected in each region R1 to R4. By providing the electrodes E1 to E4, a single detector is configured. That is, the portions corresponding to the respective X-ray detection regions R <b> 1 to R <b> 4 become the X-ray detection units 2. The collection electrodes E1 to E4 are connected to the output channels Ch1 to Ch4, respectively. The conversion unit 3 is connected to each of the plurality of output channels Ch1 to Ch4.

  Each conversion unit 3 is a charge amplifier (CSA (Charge Sensitive Amplifier)), and the charge output from each X-ray detection unit 2 is integrated and amplified by an operational amplifier 31 and a capacitor 32, and is proportional to the energy of X-rays. The signal is converted into a voltage signal (analog signal). Each converter 3 includes an operational amplifier 31, a capacitor 32 connected between the input terminal (inverting input terminal) and the output terminal of the operational amplifier 31, a semiconductor switch (for example, FET) that resets (discharges) the charge of the capacitor 32, and the like. Switch 33.

The switch 33 is controlled on and off by the reset control unit 5.
The reset control unit 5 outputs a reset signal for turning on the switch 33 for a predetermined time, and discharges and resets the accumulated charge of the capacitor 32 corresponding to the switch 33.

  Specifically, the reset control unit 5 acquires a voltage signal output from each operational amplifier 31, compares it with a predetermined reset start threshold value, and responds to the capacitor 32 when the voltage signal exceeds the reset start threshold value. A reset signal is output to the switch 33 to turn on the switch 33. Further, the reset control unit 5 compares the voltage signal with a predetermined reset end threshold value, and turns off the switch 33 when the voltage signal becomes equal to or lower than the reset end threshold value. Alternatively, the reset control unit 5 outputs a reset signal to the switch 33 and turns off the switch 33 after a predetermined period of time has elapsed. Note that voltage detection means for detecting the voltage of each capacitor 32 is provided, and the reset control unit 5 responds to the integration capacitor 32 when the voltage obtained by the voltage detection means reaches a predetermined voltage value. The reset signal may be output to the switch 33 that performs the above operation. In addition, the reset control unit 5 may be configured to output a reset signal for each reset period preset for each integration capacitor 32.

  Here, when the switch 33 is an FET, the reset signal is a pulse signal whose gate voltage is a gate threshold voltage (for example, 0 V) and whose gate voltage is equal to or higher than the gate threshold voltage and constant for a predetermined time. .

  The signal processing unit 4 includes a waveform shaping unit 41 that shapes the voltage signal from the conversion unit 3 into a pulse signal, a wave height detection unit 42 that detects a peak value of the pulse signal shaped by the waveform shaping unit 41, and a wave height detection unit. And a counting unit 43 that counts the peak value obtained by 42 for each peak.

  The waveform shaping unit 41 and the wave height detection unit 42 are digital pulse processors (DPP (Digital Pulse Processor)), and a plurality of waveform shaping units 41 and wave height detection units 42 are provided corresponding to the plurality of conversion units 3.

  The waveform shaping unit 41 generates, for example, a trapezoidal waveform pulse signal (digital signal) from the voltage signal converted by the conversion unit 3. The peak value of this pulse signal is proportional to the energy of X-rays. Moreover, the wave height detection unit 42 detects the wave height value of the input pulse signal by peak hold.

  Here, the waveform shaping unit 41 of this embodiment includes a slow waveform output unit and a fast waveform output unit. The slow waveform output unit has a high resolution with respect to the energy of the X-ray, and by filtering the voltage signal from the conversion unit 3 using a large time constant, a trapezoidal waveform having a large time width is obtained. A pulse signal is generated. The pulse signal having a large time width obtained by the slow waveform output unit is output to the wave height detection unit 42 and the count unit 43 and used to generate X-ray information. The fast system waveform output unit has a high time resolution for detecting X-ray incidence, and the voltage signal from the conversion unit 3 is filtered using a time constant smaller than that of the slow system waveform output unit. By doing so, a pulse signal (timing pulse) with a small time width is generated. The pulse signal with a small time width obtained by the fast system waveform output unit is not only used for pile-up detection, but also output to the reset detection unit 6 to be described later to reset the conversion unit 3. Used for detection.

  The count unit 43 is a multi-channel analyzer (MCA), and is a single unit that processes the peak values obtained by the plurality of peak detectors 42. The count unit 43 counts the number of times the pulse height of the pulse signal is input for each wave height, and generates an X-ray spectrum that is X-ray information.

  Thus, as shown in FIGS. 2 and 4, the X-ray detection apparatus 100 according to the present embodiment uses any pulse signal obtained from the voltage signals from the plurality of conversion units 3, A reset information acquisition unit 6 that acquires reset information indicating that the reset has been performed is provided.

  As shown in FIG. 4, the reset information acquisition unit 6 receives a pulse signal (output waveform) obtained by the fast waveform output unit of each waveform shaping unit 41, and uses any of the pulse signals to convert any of the conversion units. 3 includes a reset information detecting unit 61 that detects reset information indicating that the resetting 3 is reset. Hereinafter, the conversion unit to which the reset signal is output is also referred to as a reset conversion unit 3A. Specifically, the reset information detection unit 61 compares the pulse signal obtained by the fast waveform output unit of each waveform shaping unit 41 with a predetermined reset detection threshold (for example, a negative value) (FIG. 5C, ( D)). Then, when the output signal falls below a predetermined threshold, the reset information detection unit 61 sets the conversion unit 3 connected to the waveform shaping unit 41 that has output the output signal that has fallen below as the reset conversion unit 3A.

  Further, as shown in FIG. 5D, the reset information detection unit 61 detects the timing when the output signal falls below the predetermined threshold as the reset start time. Further, after detecting the reset start time, the reset information detection unit 61 detects a timing when the pulse signal exceeds the predetermined threshold as a reset end time. Information detected by the reset information detection unit 61 is stored in the reset information storage unit 62. The reset information is stored in the reset information storage unit 62 only by being stored for a short time or being transferred from the reset information detection unit 61 to the signal processing unit 4 (reset information passes). Including. In addition, the reset information acquisition unit 6 outputs a detection signal including information on the reset start point and reset end point to the signal processing unit 4 together with the information on the reset conversion unit 3A.

  Note that the reset information detection unit 61, when the change amount of the pulse signal obtained by the fast waveform output unit (difference between the pulse signal at time t + 1 and the pulse signal at time t) exceeds a predetermined threshold, The conversion unit 3 connected to the waveform shaping unit 41 that outputs the pulse signal may be detected as the reset conversion unit 3A. In addition, the reset information detection unit 61 outputs the voltage signal when the amount of change in the voltage signal output from the conversion unit (difference between the voltage signal at time t + 1 and the voltage signal at time t) exceeds a predetermined threshold. The output conversion unit 3 may be detected as the reset conversion unit 3A.

  When the signal processing unit 4 of the present embodiment generates the X-ray information using the voltage signal from the conversion unit 3B different from the reset conversion unit 3A, the signal processing unit 4 is caused by the reset signal to the reset conversion unit 3A. Remove crosstalk noise.

  Here, another conversion unit 3B is, for example, a conversion unit (not limited to one) adjacent to the reset conversion unit 3A. This is because the conversion unit 3B adjacent to the reset conversion unit 3A is considered to be most affected by the crosstalk noise. The conversion unit 3B adjacent to the reset conversion unit 3A is a conversion unit connected to the output channel Ch adjacent to the output channel Ch to which the reset conversion unit 3A is connected.

  Specifically, the signal processing unit 4 includes a noise removing unit 44 that removes noise from the peak value obtained by the wave height detecting unit 42 based on the reset information obtained by the reset information detecting unit 61.

  The noise removing unit 44 removes a signal (crest value) from the other conversion unit 3B that is affected by noise caused by reset. Specifically, the noise removing unit 44 removes the peak value generated by the crosstalk noise from the peak value obtained by the voltage signal from the other conversion unit 3B from the count by the counting unit 43. To do.

  More specifically, the noise removing unit 44 removes a peak value included in a predetermined period determined based on the reset start time and the reset end time obtained by the reset information detecting unit 61. Here, the predetermined period is a period that is set in advance and includes a period from the time when the crosstalk noise occurs at the rising edge of the reset signal to the time when the crosstalk noise generated at the falling edge of the reset signal attenuates to a negligible level. It is. In the present embodiment, the peak value included in the first predetermined period determined based on the reset start point and the peak value included in the second predetermined period determined based on the reset end point are removed. Other peak values from which the peak value caused by the crosstalk noise has been removed by the noise removing unit 44 are counted by the counting unit 43. The function of the noise removing unit 44 may be provided in the counting unit 43.

<Effect of this embodiment>
According to the X-ray detection apparatus 100 of the present embodiment configured as described above, the reset information indicating that any of the conversion units 3 (3A) has been reset using the voltage signals from the plurality of conversion units 3. Since the noise caused by the reset is removed from the voltage signal from the conversion unit 3B different from the conversion unit 3A, the resolution of the X-ray spectrum is reduced due to the crosstalk of the reset signal, or low energy It is possible to prevent a pseudo spectrum from being formed in the region. In addition, every conversion unit 3A is not configured to take in a signal from the radiation detection unit 2 every time one of the conversion units 3A is reset as in the synchronous reset method, thereby suppressing an increase in dead time. Can do. Furthermore, since it is detected that any of the conversion units 3 has been reset using the voltage signal from the conversion unit 3, there is no need to acquire reset information from the reset control unit 5.

  The present invention is not limited to the above embodiment.

  For example, the signal processing unit of the embodiment is configured to remove noise from the peak value before being input to the counting unit, but in addition, the crosstalk noise is removed as follows. Also good.

  That is, as shown in FIGS. 6 and 7, the X-ray detection apparatus 100 detects the delay unit 45 when the delay unit 45 that delays the voltage signal from the conversion unit 3 and the reset conversion unit 3 </ b> A are detected. And a noise removal unit 46 that removes crosstalk noise from the voltage signal of another conversion unit 3B delayed by 45 based on reset information.

  Then, as shown in FIG. 8, the X-ray detection apparatus 100 inputs the voltage signal before being delayed to the fast waveform output unit of the waveform shaping unit 41, and the conversion unit 3 </ b> A reset by the reset information detection unit 61. Is detected (see FIG. 8A). As shown in FIG. 7, the reset information acquisition unit 6 outputs the reset information from the reset information detection unit 61 to a noise removal unit 45 corresponding to another conversion unit 3B, and the noise removal unit 45 includes the delay unit. Crosstalk noise is removed by linear interpolation or the like with values before and after a predetermined removal period from the voltage signal of another conversion unit 3B delayed by 44 (see FIGS. 8C and 8D).

  In this way, in another conversion unit 3B, the voltage signal from which the crosstalk noise has been removed by the noise removal unit 45 is input to the waveform shaping unit 41, and the waveform is shaped by the slow waveform output unit of the waveform shaping unit 41. Thus, a pulse signal is generated. The crest value of the pulse signal is detected by the crest detector 42 and counted by the crest 43 by the crest.

  In the embodiment, the noise removing unit 44 is configured to remove the crest values included in each of the first predetermined period and the second predetermined period. However, the noise removing unit 44 is continuous including the reset start time and the reset end time. You may comprise so that the peak value contained in a period may be removed.

  Moreover, the reset information acquisition part 6 of the said embodiment may acquire only one of the reset start time or the reset end time. In this case, the noise removing unit 44 is configured to remove a peak value included in a predetermined period based on the reset start time or a predetermined period based on the reset end time.

  Further, the noise removing unit 44 removes the peak value included in the predetermined period based on the reset start time or the predetermined period based on the reset end time, and also integrates signals from a plurality of conversion units or signals obtained therefrom. By comparing a predetermined upper threshold and / or lower threshold, the signal or peak value may be removed as noise from their magnitude relationship. Furthermore, the noise removing unit 44 not only removes the signal included in the predetermined period, but also applies the noise of the signal included in the predetermined period to them using a reference value or a range that is predetermined by experiments or the like. Depending on whether or not, the specified noise may be removed.

  In addition, the noise removal unit 44 of the above embodiment is configured to remove noise from the peak value input to the count unit 43 provided in the previous stage of the count unit 43. The counter may be configured to remove the count due to noise from the count value obtained by the count unit 43. Specifically, using the reset start time or reset end time stored by the noise information storage unit 62 of the noise information acquisition unit 6, the value counted during a predetermined period determined based on the reset start time or reset end time is calculated. It is conceivable to subtract and remove.

  Further, the noise removing unit 44 may be provided in the previous stage of the waveform shaping unit 41, or may be provided between the waveform shaping unit 41 and the wave height detection unit 42.

  In the above embodiment, the waveform shaping unit and the wave height detection unit are configured by a pulse counter, and the count unit is configured by a multi-channel analyzer. However, for example, a dedicated or general-purpose computer (CPU, memory, AD converter, etc.) May be used.

  In the above embodiment, a plurality of pulse processors (waveform shaping unit and wave height detection unit) are provided corresponding to the plurality of conversion units 3, but a shared pulse processor may be used for the plurality of conversion units 3. good.

  In the embodiment, the reset information acquisition unit 6 is common to the plurality of conversion units 3, but a plurality of reset information acquisition units 6 are provided corresponding to the plurality of conversion units 3, respectively. Alternatively, it may be shared by some of the plurality of conversion units 3.

  In the embodiment, one reset control unit 5 outputs a reset signal to a plurality of conversion units 3. However, as a configuration in which a plurality of reset control units 5 are provided corresponding to the plurality of conversion units 3. Also good.

  In the embodiment, the crosstalk noise correction process is performed on the conversion unit 3 adjacent to the reset conversion unit 3, but the crosstalk noise correction process is performed on the other conversion units 3. It may be.

  Further, the converter 3 connected to the output channel Ch which is sufficiently separated from the channel to which the reset converter 3 is connected and the crosstalk noise does not substantially become a problem, and other crosstalk measures such as a shield are provided. The conversion unit 3 connected to the existing channel Ch may not perform the crosstalk noise correction process. It should be noted that being sufficiently away from the channel to which the reset conversion unit 3 is connected includes being away from a predetermined distance determined in advance by experiments or the like.

  Further, in the above embodiment, the crosstalk noise via the output channel of the X-ray detection unit 2 has been described. However, the crosstalk noise via the channel of the signal processing unit 4, the X-ray detection unit, and the conversion unit 3 are mounted. The same applies to the crosstalk between the wirings on the substrate or between the wirings from the substrate to the signal processing unit 4.

  Furthermore, as the X-ray detector, other semiconductor detectors such as a Si (Li) type detector can be used.

  In addition, it goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

ADVANTAGE OF THE INVENTION According to this invention, while reducing the bad influence by the crosstalk of a reset signal in a radiation detection apparatus, the increase in dead time (dead time) can be suppressed.

Claims (7)

A plurality of radiation detectors for outputting charges generated by the incidence of radiation;
A plurality of conversion units that are provided corresponding to the plurality of radiation detection units and convert the integrated amount of the generated charges into an integrated signal according to the integrated amount;
A signal processing unit that processes integrated signals from the plurality of conversion units to generate radiation information;
A reset control unit that outputs a reset signal to the conversion unit to reset the charge accumulated in the conversion unit;
A reset information acquisition unit that acquires reset information indicating that any of the conversion units has been reset using an integrated signal from the plurality of conversion units or a signal obtained therefrom,
The signal processing unit includes a noise removing unit that removes noise caused by the reset from an integrated signal from a conversion unit different from the converted conversion unit or a signal obtained therefrom based on the reset information. Detection device. The reset information acquisition unit is for acquiring a reset start point by a change in the integrated signal or a signal obtained therefrom,
2. The noise removing unit removes a signal of a predetermined period determined based on the reset start time from an integrated signal from a conversion unit different from the reset conversion unit or a signal obtained therefrom. Radiation detection equipment. The reset information acquisition unit acquires a reset end point by a change in the integrated signal or a signal obtained therefrom,
2. The noise removing unit removes a signal of a predetermined period determined based on the reset end point from an integration signal from a conversion unit different from the reset conversion unit or a signal obtained therefrom. Radiation detection equipment. The signal processing unit
A waveform shaping unit for shaping the integrated signal from the conversion unit into a pulse signal;
A pulse height detection unit for detecting a peak value of the pulse signal shaped by the waveform shaping unit;
The wave height value obtained by the wave height detection unit further comprises a counting unit that counts by wave height,
The radiation detecting apparatus according to claim 2 or 3, wherein the noise removing unit removes noise from a peak value obtained by the peak detecting unit based on the reset information. The signal processing unit
A delay unit for delaying the integrated signal from the conversion unit for a predetermined time;
A waveform shaping unit that shapes the integrated signal delayed by the delay unit into a pulse signal;
A pulse height detection unit for detecting a peak value of the pulse signal shaped by the waveform shaping unit;
The wave height value obtained by the wave height detection unit further comprises a counting unit that counts by wave height,
The radiation detection apparatus according to claim 2, wherein the noise removing unit removes crosstalk noise from the integrated signal delayed by the delay unit based on the reset information.   The radiation detection apparatus according to claim 1, wherein the plurality of radiation detection units are configured such that a surface of a semiconductor block is divided into a plurality of radiation detection regions, and a collection electrode is provided in each region. A plurality of conversion units that are provided corresponding to a plurality of radiation detection units that output charges generated by the incidence of radiation, and convert the integrated amount of the generated charges into an integrated signal corresponding to the integrated amount;
A signal processor that processes integrated signals from the plurality of converters to generate radiation information;
A reset control unit that outputs a reset signal to the conversion unit to reset the charge accumulated in the conversion unit;
A reset information acquisition unit that acquires reset information indicating that any of the conversion units has been reset using an integrated signal from the plurality of conversion units or a signal obtained therefrom,
The signal processing unit according to claim 1, wherein the signal processing unit includes a noise removing unit that removes noise caused by the reset based on the reset information.

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