Radiation detector, trigger signal generator, and radiation analysis system

Abstract

To provide a radiation detector capable of highly accurately and highly efficiently synchronizing an external circuit by generating a trigger-out signal independent of an exposure or readout signal, trigger signal generator, and radiation analysis system.SOLUTION: A radiation detector includes a sensor 110 for generating a pulse when radiation particles are detected by exposure, counters 140 provided to be able to count the pulse for every frame, a readout circuit 150 for reading a count value made by the counters 140, a control circuit 160 for controlling exposure and readout by a signal, and a trigger signal generating circuit 170, when one or a series of prescribed number of frames in which a high or low section is set, are defined as one unit frame, for generating a trigger out signal for specifying the set high or low section.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a radiation detector that generates a trigger-out signal for synchronization with an external circuit, a trigger signal generator, and a radiation analysis system including the same. [Background technology]

[0002] Conventionally, a technique for synchronizing the exposure of a radiation detector with a control signal from an external device is known (see Non-Patent Document 1). For example, in the system described in Non-Patent Document 1, trigger pulses are generated when the sample passes each position at regular intervals based on a calculated trajectory during continuous scanning, and a ptychographic data set is recorded at a maximum of 9 kHz. In this way, a control signal from an external device may be used as a synchronization signal, and in other cases, a signal that specifies the start and end of the exposure time of the radiation detector may be used as a synchronization signal.

[0003] However, in recent years, radiation detectors that perform exposure in various ways have been developed. For example, imaging in special modes such as continuous exposure (zero dead) and burst is known (see Patent Document 1 and Non-Patent Document 2). The radiation detector described in Patent Document 1 performs continuous exposure by switching between multiple counters that count pulses. The radiation detector described in Non-Patent Document 2 uses a pixel with two 14-bit counters to continuously measure 14 2-bit frames at high speed and read them out collectively in 28 bits.

[0004] Also known is imaging using high-speed exposure in an iterative mode or the like (see Patent Document 2). The radiation detector described in Patent Document 2 uses a switching circuit to read out count values ​​obtained by counting pulses generated by a sensor when a radiation particle is detected, using two counters at their respective threshold values. [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] “High-speed X-ray ptychographic tomography”, Darren Batey, Christoph Rau & Silvia Cipiccia, Scientific Reports, 12 May 2022 [Non-Patent Document 2] “Sub-microsecond-resolved multi-speckle X-ray photon correlation spectroscopy with a pixel array detector”, Qingteng Zhang, Eric M. Dufresne, Suresh Narayanan, Piotr Maj, Anna Koziol, Robert Szczygiel, Pawel Grybos, Mark Sutton and Alec R. Sandy, Journal of Synchrotron Radiation (2018). 25, 1408-1416 [Patent documents]

[0006] [Patent Document 1] Patent No. 6182758 [Patent Document 2] Patent No. 7088555 Summary of the Invention [Problem to be solved by the invention]

[0007] However, when imaging in a special mode such as continuous exposure or burst, the exposure time remains high during measurement of a series of frames, and the signal specifying the start and end of the exposure time cannot be used as a synchronization signal with an external device. Also, in imaging using high-speed exposure, the exposure time is too short to detect the signal specifying the start and end of the exposure time as a synchronization signal. If the signal specifying the start and end of the exposure time is used as a synchronization signal as it is, it may be difficult to synchronize with an external device.

[0008] The present invention has been made in consideration of the above circumstances, and aims to provide a radiation detector, a trigger signal generator, and a radiation analysis system that can synchronize an external circuit with radiation detection with high accuracy and high efficiency by generating a trigger out signal that is not based on exposure or readout signals. [Means for solving the problem]

[0009] (1) In order to achieve the above object, the radiation detector of the present invention is a radiation detector that generates a trigger out signal for synchronization with an external circuit, and is characterized by comprising: a sensor that generates a pulse when a radiation particle is detected by exposure, a counter that is arranged to be able to count the pulses for each frame, a readout circuit that reads out the count value obtained by the counter, a control circuit that controls the exposure and the readout by a signal, and a trigger signal generating circuit that generates a trigger out signal that specifies the set High and Low sections when one frame or a series of a predetermined number of frames in which a High or Low section is set is represented as one unit of frame.

[0010] (2) In the radiation detector described in (1), the start point or end point of the High and Low sections is set at either the rising edge or the falling edge of an exposure time of the one unit frame, or at either the rising edge or the falling edge of a readout time of the one unit frame.

[0011] (3) In the radiation detector according to (1) or (2), the High and Low periods each include a readout time for one unit of frame.

[0012] (4) In the radiation detector described in (3), the High and Low sections are set to either one at the rising edge of the exposure time of the one unit frame and are constant for the same measurement.

[0013] (5) Furthermore, in the radiation detector described in (3), the exposure time for one frame is 1000 μsec or less.

[0014] (6) In the radiation detector described in any one of (1) to (5), the counter is provided in plurality, and the control circuit switches between a counter that counts the pulses and a counter from which the count value is read out, among the plurality of counters, at the timing of generating the trigger out signal, thereby performing continuous exposure.

[0015] (7) In the radiation detector described in (6), the unit frame is one frame, and the trigger signal generating circuit generates a trigger out signal in which high and low intervals are defined for each rising edge of the exposure time of each frame.

[0016] (8) In the radiation detector described in any one of (1) to (7), the High and Low sections do not include the readout time of the one unit frame, are set by the rise and fall of the exposure time of the one unit frame, and are constant for each measurement.

[0017] (9) In addition, the radiation detector according to any one of (1) to (8) further comprises a mode switching circuit which switches the settings of the timing of the exposure and the readout between predetermined modes, the control circuit controls the exposure and the readout by a signal according to the predetermined mode, and the trigger signal generating circuit generates a trigger out signal having high and low intervals defined according to the predetermined mode.

[0018] (10) Furthermore, the trigger signal generator of the present invention generates a trigger out signal for synchronizing an external circuit with a radiation detector that counts pulses generated for each frame when radiation particles are detected by exposure, and is characterized in that when one frame or a series of a predetermined number of frames in which a high or low section is set is represented as one unit of frame, the trigger signal generator generates a trigger out signal that specifies the set high and low sections when the frame is connected to the radiation detector.

[0019] (11) Furthermore, a radiation analysis system of the present invention is a radiation analysis system that acquires a radiation intensity distribution for each frame, and is characterized in that it includes a radiation detector described in any one of (1) to (9) and a synchronization circuit that operates in synchronization with a trigger out signal generated by the radiation detector.

[0020] (12) Furthermore, in a radiation analysis system of the present invention, there is provided a radiation analysis system that acquires a radiation intensity distribution for each frame, characterized in that it comprises a trigger signal generator as described in (10), a radiation detector connected to the trigger signal generator, and a synchronization circuit that operates in synchronization with the trigger out signal generated by the trigger signal generator. [Brief description of the drawings]

[0021] [Figure 1] FIG. 1 is a schematic diagram mainly showing the configuration of a radiation detector according to a first embodiment. [Diagram 2] 4 is a flowchart mainly showing the operation of the radiation detector of the first embodiment. [Diagram 3] 11 is a timing chart for generating a trigger-out signal based on the operation of continuous exposure. [Figure 4] 1A and 1B are schematic diagrams showing the conventional and present invention ptychography measurement methods, respectively. [Diagram 5] 13A and 13B are schematic diagrams showing waveform reproduction when the period of the trigger out signal is long and short relative to the sampling period of the external synchronization circuit, respectively. [Figure 6] 11 is a timing chart showing a trigger-out signal when continuous exposure is not performed. [Figure 7] FIG. 11 is a schematic diagram showing the configuration of a radiation detector according to a second embodiment. [Figure 8] 11 is a timing chart showing an operation in an iterative mode. [Figure 9] 4 is a timing chart showing an operation in a burst mode. [Figure 10] FIG. 11 is a plan view showing the configuration of a radiation analysis system according to a third embodiment. [Figure 11] FIG. 13 is a side view showing the configuration of a radiation analysis system according to a fourth embodiment. [Figure 12] FIG. 13 is a side view showing the configuration of a radiation analysis system according to a fifth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Next, an embodiment of the present invention will be described with reference to the drawings. In order to facilitate understanding of the description, the same reference numerals are used to refer to the same components in each drawing, and duplicated description will be omitted.

[0023] [First embodiment] (Configuration of Radiation Detector) 1 is a schematic diagram mainly showing the configuration of a radiation detector 100. The radiation detector 100 is a detector that detects radiation while generating a trigger-out signal for synchronization with an external synchronization circuit 210. The radiation detector 100 is preferably a semiconductor detector having a two-dimensional data buffer function. The radiation to be detected is likely to function well when it is X-rays, but is not limited thereto and may be α rays, β rays, γ rays, neutron rays, etc. The radiation detector 100 may be a one-dimensional detector.

[0024] The external synchronization circuit 210 is a circuit that synchronizes with the trigger-out signal generated by the radiation detector 100 at a predetermined sampling rate. For example, a radiation irradiation system for ptychography or a sample support mechanism can be connected to the external synchronization circuit 210 to correct the radiation irradiation position. The external synchronization circuit 210 can transmit a trigger-in signal to start measurement by the radiation detector 100. For example, a shutter operation signal is the trigger-in signal. The radiation detector 100 and the external synchronization circuit 210 constitute a radiation analysis system 200.

[0025] As shown in FIG. 1, the radiation detector 100 includes a sensor 110, a detection circuit 120, a switching circuit 130, first and second counters 140a, 140b, a readout circuit 150, a control circuit 160, a trigger signal generating circuit 170, and a mode switching circuit 180.

[0026] The sensor 110 generates a pulse when a particle of radiation is detected by exposure. The sensor 110 can detect the intensity of the X-ray flux incident on the light receiving surface as surface information. Note that while Fig. 1 shows a configuration for one sensor 110 for convenience, the radiation detector 100 basically includes multiple sensors and configurations for those sensors.

[0027] When the exposure time is High, the detection circuit 120 judges whether the pulse is higher than a reference value, and if it is higher, sends it as a voltage signal to one of the counters 140a, 140b that is currently counting. When the switching circuit 130 receives a counter switching signal from the control circuit 160, it switches the counter that counts the voltage signal. The two counters 140a, 140b each have the same function and can count pulses. The pulses can be counted for each frame. A frame is a time during which an operation to take one image is performed. For normal exposure and continuous exposure, a frame is specified by the exposure time of one image, but in the 2S mode described later, a frame is specified by the combined time of the exposure time and the readout time. The readout circuit 150 reads out the count value from the counter that has just finished counting. The memory in the readout circuit 150 stores the readout count value.

[0028] The control circuit 160 starts measurement when it receives a trigger-in signal. The control circuit 160 sends a signal to the trigger signal generation circuit 170 when controlling exposure and readout. Also, when switching between the counters that count pulses among the multiple counters, the control circuit 160 makes the trigger signal generation circuit 170 generate a trigger-out signal. Between the timings at which the trigger-out signal is generated, the readout circuit 150 reads from the counter 140a that has just finished counting, enabling continuous exposure.

[0029] In this way, the control circuit 160 performs continuous exposure by switching between the counter that counts pulses and the counter whose count value is read out, among the multiple counters, at the timing when the trigger signal generating circuit 170 generates a trigger out signal. This makes it possible to synchronize the external synchronization circuit 210 with radiation detection while maintaining the duty ratio of continuous exposure.

[0030] The trigger signal generating circuit 170 generates a trigger out signal that specifies the set High and Low sections when one frame or a series of a predetermined number of frames in which a High or Low section is set is expressed as one unit frame. In other words, signals corresponding to the rising and falling edges of the High and Low sections of one unit frame can be used as the trigger out signal. In this way, by generating a trigger out signal that is not based on exposure or readout signals, it is possible to synchronize the external synchronization circuit 210 with radiation detection with high accuracy and high efficiency. At this time, it is the trigger out signals of the rising and falling edges of the frame that specify the exposure time.

[0031] The start or end points of the High and Low periods can be set to either the rising or falling edge of the exposure time of one unit frame, or to either the rising or falling edge of the readout time of one unit frame. This makes it possible to set the High and Low periods according to the application or measurement conditions and generate a trigger out signal that is suitable for the situation.

[0032] Particularly in the continuous exposure mode, one unit frame is one frame, and it is preferable that the trigger signal generating circuit 170 generates a trigger out signal in which a high and low section is defined for each rising edge of the exposure time of each frame. This makes it possible to synchronize radiation detection with an external circuit with a highly efficient duty ratio in continuous exposure.

[0033] The mode switching circuit 180 can switch the exposure and readout timing settings between predetermined modes. The switching is preferably performed under control from, for example, a PC in response to an instruction from an adjuster or a user. For example, the setting can be changed so as to generate a trigger out signal having a waveform that matches the sampling rate of the external synchronization circuit 210. The predetermined modes include, for example, a normal mode, a continuous exposure mode, an iterative mode, and a burst mode.

[0034] The control circuit 160 controls exposure and readout by signals according to a predetermined mode, and the trigger signal generation circuit 170 generates a trigger out signal that specifies high and low intervals according to the predetermined mode. This makes it possible to generate a trigger out signal for a predetermined mode that is switched according to the application and measurement conditions.

[0035] (Radiation detector operation) A description will be given of the operation of the radiation detector 100 configured as above. Fig. 2 is a flowchart showing the operation of the radiation detector 100. Note that the operation in the continuous exposure mode shown in Fig. 2 is an example, and the operation is not limited to this.

[0036] First, radiation is irradiated onto a sample (step S1). When a particle of radiation that has entered the detection surface is detected by sensor 110, a pulse is generated. First, one of the counters starts measuring radiation (step S2), and trigger signal generating circuit 170 generates a trigger out signal that specifies a High section. Pulses are counted by one of the counters. Then, control circuit 160 operates in response to a signal that specifies the start and end of the exposure time, thereby switching the counter that counts pulses from among multiple counters 140a, 140b (step S3).

[0037] At the same time as the counter is switched, the read circuit 150 starts reading out the count data from the counter that has finished counting, and at the same time, the trigger signal generation circuit 170 generates a trigger out signal in a low section (step S4). The counter that is counting maintains its count, and reading out the count data from the counter that has finished counting prior to the counter switching timing is completed (step S5).

[0038] Thereafter, it is determined whether the measurement has been completed (step S6), and if the measurement has not been completed, the process returns to step S3, and the counter is switched after waiting for the High section of the exposure time, and the trigger signal generating circuit 170 generates a trigger out signal that specifies the High or Low section. In this manner, steps S3 to S6 are repeated until the measurement is completed. On the other hand, if it is determined in step 6 that the measurement has been completed, the counting is stopped and the measurement is terminated.

[0039] (Timing chart for continuous exposure) Next, the trigger out signal will be explained using a timing chart. FIG. 3 is a timing chart showing the operation of continuous exposure. "Command" shown in FIG. 3 indicates the time point when the command to start measurement is issued. "Exposure" indicates the High and Low intervals of the exposure time. "ReadoutTime" indicates the readout time specified by the ON and OFF of the readout operation. The radiation detector 100 first performs a dummy readout operation, alternately switching between the two counters and detecting radiation by continuous exposure without dead time. "e" indicates the exposure time, and "Rt" indicates the readout time.

[0040] "EN OUT (exposure)" indicates the high and low intervals of the exposure time. The ENOUT signal shown in this chart is a signal that specifies the start and end of the exposure time, and is a trigger-out signal. In the continuous exposure mode, after the dummy read operation, the high interval continues without a gap, and the start of the read operation before the end of the measurement is the falling edge of the high interval. If this is used as a trigger-out signal for synchronizing with the external synchronization circuit 210, the signal does not change even after the exposure of one frame is completed, so it is not possible to operate according to the exposure of one frame.

[0041] "EN OUT (Iteration)" indicates the high and low intervals of the iterative mode time during which exposure is repeated in one measurement. "ENOUT (Start to Stop)" indicates the high and low intervals of the measurement time from the start to the end of measurement.

[0042] "EN OUT (even / odd)" indicates alternating High and Low intervals for each frame. The High interval is from the start to the end of exposure for odd-numbered frames, and the Low interval is from the start to the end of exposure for even-numbered frames. By switching the H / L logic for even / odd exposure, it is possible to generate a signal that detects the frame position.

[0043] The trigger signal generating circuit 170 can perform efficient and reliable synchronization by generating an ENOUT signal that specifies the start and end of such a frame as a trigger out signal for synchronization with the external synchronization circuit 210. The external synchronization circuit 210 detects both the rising and falling edges of the trigger out signal. The meanings of the names and symbols in the timing charts are the same in the following explanations unless otherwise specified.

[0044] (Application to ptychography) 4(a) and (b) are schematic diagrams showing the conventional and present invention ptychography measurement methods, respectively. In Fig. 4(a) and (b), the configuration of the X-ray irradiation system consisting of the X-ray source 10 and the zone plate 20 and the sample S0 are the same. However, the radiation detector 900 does not have a trigger-out signal generation circuit, whereas the radiation detector 100 has a trigger signal generation circuit. The zone plate 20 can manipulate the irradiation position on the sample S0, making it possible to measure the ptychography.

[0045] In the example shown in Fig. 4(a), if the signal that specifies the start and end of the exposure time is used as the trigger-out signal, continuous exposure is not possible, and it is necessary to provide a dead time after the exposure section. If position detection is performed on the rising edge of the trigger-out signal, position detection is not performed until the seventh sampling after the first sampling, and the high sampling rate cannot be utilized.

[0046] In the example shown in FIG. 4(b), a trigger-out signal with alternating high and low intervals is generated for each exposure of a frame, allowing for continuous exposure. Position detection is possible at the rising and falling edges of the trigger-out signal, and after the first sampling, position detection is possible at the fourth and seventh samplings, allowing for efficient ptychography measurement. The radiation detector 100 can be used to correct the position accuracy of synchrotron radiation applications such as tomography as well as ptychography. It is also suitable for applications that require temporal consistency between exposure and physical quantities such as temperature.

[0047] (High-speed exposure) In the normal mode, continuous exposure by switching the counter is not performed, and counting is ended and readout is started, for example, by a signal from an external device. When performing high-speed exposure in the normal mode without switching the counter, if a signal specifying the start and end of a short exposure time is used as a trigger-out signal, the external synchronization circuit 210 cannot detect the high section of the trigger-out signal. Figures 5(a) and (b) are schematic diagrams showing waveform reproduction when the period of the trigger-out signal is long and short relative to the sampling period of the external synchronization circuit, respectively.

[0048] In the example of Fig. 5(a), the period of the trigger-out signal is longer than the sampling period, so the waveform of the trigger-out signal is reproduced as is. In the example of Fig. 5(b), the period of the trigger-out signal is shorter than the sampling period, so a waveform different from the original waveform is reproduced.

[0049] In this way, in order for the external synchronization circuit 210 to accurately recognize the trigger-out signal, it is preferable that the period of the trigger-out signal is relatively long. Therefore, it is preferable that the High and Low sections each include the readout time of one unit of frame. As a result, even if the external circuit cannot detect a signal that specifies the start and end of the exposure time due to high-speed exposure, a detectable trigger-out signal can be generated as long as the readout time is sufficiently long compared to the exposure time.

[0050] From the viewpoint of the length of the period of the trigger-out signal, the high and low sections may each be set to the exposure time of two or more frames. It is also preferable that the high and low sections are set to either one at the rising edge of the exposure time of one unit frame, and are constant for the same measurement. A trigger-out signal in which high and low states of a constant length are repeated alternately is easy to detect.

[0051] For example, if the synchronous CLK is about 20 kHz, the gap time of the trigger-out signal must be set to 100 μsec or more. If the signal specifying the start and end of the exposure time is used as the trigger-out signal as is, the measurement time for one frame will be 200 μsec, which is the sum of the exposure time of 100 μsec and the gap time of 100 μsec, and the exposure time will be significantly reduced in measurements of 5 kfps or more. By generating a trigger-out signal that maintains a high or low logic of 100 μsec or more separately from the signal specifying the start and end of the exposure time and using the external synchronization circuit 210 for edge detection, it is possible to simply improve the frame rate from 5 kHz measurement to 10 kHz measurement.

[0052] By sending a signal that sums up the number of frames, it may be possible to measure two applications simultaneously. For example, you can measure ptychography with a trigger out signal that has high and low periods set over a measurement time of 10 frames, and perform a different measurement with another application.

[0053] (Application to large synchrotron radiation facilities) The radiation detector 100 is suitable for use in a large-scale synchrotron radiation facility such as Spring-8, which is equipped with accelerators for accelerating and storing electrons, and experimental facilities and various auxiliary facilities for using the generated synchrotron radiation. In such a case, the radiation detector 100 is incorporated as a part of the synchrotron radiation detection equipment of the large-scale synchrotron radiation facility.

[0054] For example, in Spring-8, an electron beam generated from an electron gun is accelerated to 1 GeV by a linear accelerator, and then introduced into a synchrotron where it is accelerated to 8 GeV. This electron beam is introduced into a storage ring, and while maintaining the energy of 8 GeV, synchrotron radiation is generated by a bending magnet and an insertion light source. The generated synchrotron radiation is guided through a beamline to an experimental station installed inside or outside the storage ring building. Note that the electron beam does not basically exist continuously in the ring, but exists in a mass called a bunch. Since the radiation detector 100 can shorten the minimum interval time between exposures, it is possible to confirm the bunch structure by synchronizing the bunch structure of the synchrotron radiation facility with the operation of the detector.

[0055] In particular, when the exposure time of one frame is 1000 μsec or less, such as in measurements performed at such large synchrotron radiation facilities, the radiation detector 100 is effective. Even in such a case, the external synchronization circuit 210 can be synchronized with the trigger out signal, rather than with a signal specifying the start and end of the exposure time.

[0056] (Timing chart for high speed exposure) Figure 6 is a timing chart showing the trigger out signal when continuous exposure is not performed. In this case, after the dummy readout operation, the exposure section and the readout section continue alternately. In the case of high-speed exposure, the exposure time e becomes shorter than the readout time Rt. Note that in Figure 6, the exposure time e is shown as long for convenience, but in reality it is an extremely short time. For example, in a radiation detector with a high frame rate such as XSPA, the high section of the exposure time becomes infinitesimally short, so the signal is always invisible and synchronization with other circuits becomes impossible.

[0057] In the example shown in Figure 6, "EN OUT (even / odd)" indicates alternating high and low intervals for each frame. The high interval is from the start of exposure of the odd-numbered frame to the end of its readout, and the low interval is from the start of exposure of the even-numbered frame to the end of its readout. Since the readout time is included in each of these even / odd intervals, each interval will not be so short that it cannot be detected, even with high-speed exposure. In other words, the duty is 50%, so the above problems are eliminated and synchronization with other circuits becomes relatively easy.

[0058] "EN OUT (even / oddnum)" is a trigger out signal that specifies the high and low intervals set for each exposure time of two consecutive frames. The high and low intervals may be set based on three or more frames, not two. By using the ENOUT signal that specifies the time including the exposure time of multiple frames in this way, a trigger out signal that specifies long high and low intervals can be used. For example, even if the sampling period of the external synchronization circuit 210 cannot be improved, it is possible to lower only the frequency of the trigger out signal without sacrificing the frame rate of the measurement. As a result, the external synchronization circuit 210 can reliably detect the trigger out signal even in high-speed exposure.

[0059] A processing device having a processor and memory such as a PC may be connected to the radiation analysis system 200, and a verification screen such as a signal specifying the start and end of the exposure time and a sign chart of a trigger-out signal may be displayed in response to a user request. This allows verification of whether the trigger-out signal is generated as set. The processing device may be provided on a cloud.

[0060] [Second embodiment] (Configuration of Radiation Detector) 7 is a schematic diagram showing the configuration of a radiation detector 100a. The radiation detector 100a has a similar configuration to the radiation detector 100, but differs in that it includes multiple detection circuits 120a, 120b, multiple counters 140a, 140b, and a switching circuit 145. Since two reference values ​​(single threshold) are used, such a configuration is also called 2S.

[0061] The detection circuits 120a and 120b determine whether the pulses are higher than their respective reference values, and if so, send them as voltage signals to the counters 140a and 140b. In the example shown in Fig. 7, the reference value of the detection circuit 120a is set lower than the reference value of the detection circuit 120b.

[0062] The counters 140a and 140b can count pulses. The read circuit 150 reads out and stores the count values ​​generated by the counters 140a and 140b. The switching circuit 145 is controlled by the control circuit 160 to switch between the counters 140a and 140a to be read.

[0063] (Iterative mode) The radiation detector 100a may be set to an iterative mode, in which exposure is started in response to a trigger-in signal, a designated number of measurements are taken, and the process is repeated a predetermined number of times.

[0064] FIG. 8 is a timing chart showing the operation of the iterative mode. This is suitable for sending a command once and then operating only with the trigger-out signal. By outputting a trigger-out signal that specifies the High and Low intervals for every two sheets, the external synchronization circuit 210 can be synchronized with the exposure in the iterative mode. The High and Low intervals may be set based on multiple frames, three or more, instead of two. In the measurement that is started upon receiving a command as described above, the command generated internally functions as a trigger signal that starts the operation of the detector.

[0065] (Burst mode) The radiation detector 100a may be set to burst mode. Burst mode is a mode in which multiple counters per pixel are used to continuously expose at high speed to obtain multiple frames, which are then read out all at once. For example, if two 14-bit counters are provided per pixel, 14 frames can be continuously measured at high speed with 2 bits per pixel, and the frames can be read out all at once with 28 bits per pixel. The exposure time is faster than normal, but the readout time is longer than normal.

[0066] 9 is a timing chart showing the operation of the burst mode. If the ENOUT signal is used to specify the High section, which is the exposure time of multiple frames, and the Low section, which is the readout time, the external synchronization circuit 210 cannot synchronize with the exposure of each frame. By setting the High and Low sections at the rising and falling edges of the exposure time of one frame, it becomes possible to perform measurements synchronized with the exposure of each frame.

[0067] In this case, the high and low periods do not include the frame readout time and are constant for each measurement. This makes it possible to synchronize with an external circuit with high efficiency when, for example, in burst mode, measuring 14 frames continuously at high speed and reading them out all at once.

[0068] [Third embodiment] (Application to single crystal structure analysis equipment) 10 is a plan view showing the configuration of a radiation analysis system 300. The radiation analysis system 300 is a single crystal structure analysis device for taking an X-ray diffraction image, and includes an X-ray source 310, a sample stage 320, an arm 330, a control unit 340, and a radiation detector 100. The X-ray source 310 irradiates a sample S0 with X-rays.

[0069] The sample stage 320 and the arm 330 are linked and can be rotated around the sample S0 at a constant speed under the control of the control unit 340. The radiation detector 100 is provided at the end of the arm 330, and its movement around the sample S0 together with the arm 330 is controlled. In such an apparatus, the sample stage 320 and the arm 330 can be moved in synchronization with a trigger-out signal from the radiation detector 100. In this way, the radiation detector 100 is suitable for angle correction of a laboratory X-ray diffraction apparatus.

[0070] Also, for example, exposure can be started by a control signal for driving the arm 330, and a trigger-out signal output from the radiation detector 100 can be used while being compared with the control signal, thereby enabling angle correction of the goniometer.

[0071] [Fourth embodiment] (Application to manufacturing lines) 11 is a side view showing the configuration of a radiation analysis system. The radiation analysis system 400 is a production line capable of inspection with X-rays, and includes an X-ray source 410, a roller 420, a belt 425, a control unit 440, and a radiation detector 100. The X-ray source 410 is shutterless, and continuously irradiates a sample S0 (product) with X-rays.

[0072] The belt 425 moves due to the rotation of the roller 420, and the sample S0 moves in the direction of the arrow in the figure. The belt 425 moves at a constant speed under the control of the control unit 440. The radiation detector 100 is provided on the opposite side of the X-ray source 410 with the belt 425 and sample S0 in between, and controls the movement of the belt 425 and the sample S0.

[0073] The radiation analysis system 400 includes the radiation detector 100 as described above, and can, for example, move the sample S0 in synchronization with a trigger-out signal from the radiation detector 100 and capture an image of the sample S0 by receiving a control signal according to the moving speed. In this case, imaging can be performed with high efficiency, so that the moving speed of the product can be increased and the processing efficiency of the process can be improved.

[0074] [Fifth embodiment] (Trigger signal generator) 12 is a schematic diagram mainly showing the configuration of a radiation detector 900. The radiation detector 900 counts pulses generated when radiation particles are detected by exposure for each frame. The radiation detector 900 is configured similarly to the radiation detector 100, but does not include a trigger signal generating circuit 170. Instead, a trigger signal generator 500 is provided outside the radiation detector 900 and connected to the radiation detector 900. The trigger signal generator 500 generates a trigger out signal for synchronization with an external synchronization circuit 210. The radiation detector 900, the trigger signal generator, and the external synchronization circuit 210 constitute a radiation analysis system 600.

[0075] The external synchronization circuit 210 transmits a trigger-in signal, and the control circuit 160 in the radiation detector 900 starts measurement when it receives the trigger-in signal. The radiation detector 900 counts the pulses generated when radiation particles are detected by exposure for each frame. The trigger signal generator 500 generates a trigger-out signal for synchronization of the external synchronization circuit 210.

[0076] When one frame or a series of a predetermined number of frames is represented as one unit frame, the trigger signal generator 500 generates a trigger out signal that specifies high and low intervals set for one unit frame. This allows for highly accurate and efficient synchronization with an external circuit by generating a trigger out signal that is not dependent on exposure or readout signals. [Explanation of symbols]

[0077] 10 X-ray source 20 Zone Plate 100, 100a Radiation detector (present invention) 110 Sensors 120, 120a, 120b Detection circuit 130, 145 Switching circuit 140 Counter 140a, 140b First and second counters 150 Readout circuit 160 Control circuit 170 Trigger signal generating circuit 180 Mode switching circuit 200 Radiation Analysis System 210 External Synchronization Circuit 300 Radiation Analysis System 310 X-ray source 320 Sample stage 330 Arm 340 Control Unit 400 Radiation Analysis System 410 X-ray source 420 Lola 425 Belt 440 Control Unit 500 Trigger Signal Generator 600 Radiation Analysis System 900 Radiation detector (conventional)

Claims

1. A radiation detector that generates a trigger-out signal for synchronization with an external circuit, comprising: a sensor that generates a pulse when a particle of radiation is detected by the exposure to light; a counter capable of counting the pulses for each frame; a read circuit for reading out the count value produced by the counter; a control circuit for controlling the exposure and the reading out by a signal; a trigger signal generating circuit that generates a trigger out signal that specifies the set High and Low intervals, when one frame or a series of a predetermined number of frames in which a High or Low interval is set is represented as one unit of frame.

2. 2. The radiation detector according to claim 1, wherein a start point or an end point of the High and Low sections is set to one of a rising edge and a falling edge of an exposure time of the one unit frame, or to one of a rising edge and a falling edge of a readout time of the one unit frame.

3. 3. The radiation detector according to claim 1, wherein each of the High and Low periods includes a readout time of one unit frame.

4. 4. The radiation detector according to claim 3, wherein the High and Low sections are set at either one of the sections at the rising edge of the exposure time of the one unit frame, and are constant for the same measurement.

5. 4. The radiation detector according to claim 3, wherein the exposure time for one frame is 1000 [mu]sec or less.

6. The counter is provided in plurality, 3. The radiation detector according to claim 1, wherein the control circuit switches between one of the plurality of counters that counts the pulses and a counter from which the count value is read out, at a timing when the trigger out signal is generated, thereby performing continuous exposure.

7. The one unit frame is one frame, 7. The radiation detector according to claim 6, wherein the trigger signal generating circuit generates a trigger out signal in which a High and a Low period are defined for each rising edge of an exposure time of each frame.

8. 3. The radiation detector according to claim 1, wherein the High and Low periods do not include a readout time of the one unit frame, are set by the rising and falling periods of an exposure time of the one unit frame, and are constant for each measurement.

9. a mode switching circuit for switching the settings of the exposure and readout timings between predetermined modes; the control circuit controls the exposure and the readout by signals in accordance with the predetermined mode; 3. The radiation detector according to claim 1, wherein the trigger signal generating circuit generates a trigger out signal having High and Low periods defined according to the predetermined mode.

10. A trigger signal generator that generates a trigger-out signal for synchronizing an external circuit with a radiation detector that counts pulses generated when radiation particles are detected by exposure for each frame, A trigger signal generator which is connected to a radiation detector and generates a trigger out signal that specifies the set High and Low intervals when one frame or a series of a predetermined number of frames in which a High or Low interval is set is represented as one unit of frame.

11. A radiation analysis system for acquiring a radiation intensity distribution for each frame, comprising: A radiation detector according to claim 1 or 2, a synchronization circuit that operates in synchronization with a trigger-out signal generated by the radiation detector.

12. A radiation analysis system for acquiring a radiation intensity distribution for each frame, comprising: A trigger signal generator according to claim 10; a radiation detector connected to the trigger signal generator; a synchronization circuit that operates in synchronization with the trigger out signal generated by the trigger signal generator.

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