Radiation detectors, trigger signal generators, and radiation analysis systems

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 them.

Background Art

[0002] Conventionally, a technique for synchronizing with the exposure of a radiation detector using a control signal of an external device is known (see Non-Patent Document 1). For example, in the system described in Non-Patent Document 1, during continuous scanning, trigger pulses are generated when a sample passes through each position at regular intervals based on the calculated trajectory, and a tycographic data set is recorded at a maximum of 9 kHz. In some cases, the control signal of the external device is used as a synchronization signal, and in other cases, a signal for specifying the start and end of the exposure time of the radiation detector is 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 time) 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 a counter that counts pulses among a plurality of counters. The radiation detector described in Non-Patent Document 2 uses a pixel having two 14-bit counters to continuously measure 14 frames of 2 bits at high speed and reads them out collectively in 28 bits.

[0004] Also, imaging by high-speed exposure in an iterative mode or the like is known (see Patent Document 2). The radiation detector described in Patent Document 2 reads out the count values obtained by two counters counting the pulses generated by the sensor when radiation particles are detected at their respective thresholds using a switching circuit.

Prior Art Documents

Non-Patent Documents

[0005]

Non-Patent Document 1

[0006] [Patent Document 1] Patent No. 6182758 [Patent Document 2] Patent No. 7088555 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] However, when imaging in special modes such as continuous exposure or burst, the exposure time remains high throughout the measurement of a series of frames, and the signals that identify the start and end of the exposure time cannot be used as synchronization signals with external devices. Also, in high-speed exposure imaging, the exposure time is too short to detect the signals that identify the start and end of the exposure time as synchronization signals. Thus, using the signals that identify the start and end of the exposure time directly as synchronization signals can make it difficult to synchronize with external devices.

[0008] This invention has been made in view of these circumstances, and aims to provide a radiation detector, a trigger signal generator, and a radiation analysis system that can synchronize external circuits with high accuracy and efficiency in response to radiation detection by generating a trigger out signal that does not depend on exposure or readout signals. [Means for solving the problem]

[0009] (1) To achieve the above objective, the present invention provides 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 radiation particles are detected by exposure; a counter that is capable of counting the pulses for each frame; a readout circuit that reads out the count value made by the counter; a control circuit that controls the exposure and the readout by signal; and a trigger signal generation circuit that generates a trigger out signal that identifies the set High and Low intervals when one or a predetermined number of frames, each with a High or Low interval, is represented as one unit frame.

[0010] (2) Furthermore, the radiation detector described in (1) is characterized in that the start or end point of the High and Low intervals is 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.

[0011] (3) In addition, the radiation detector described in (1) or (2) is characterized in that the High and Low intervals each include the readout time of one unit frame.

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

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

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

[0015] (7) In addition, in the radiation detector described in (6), the one unit frame is one frame, and the trigger signal generation circuit is characterized in that it 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 addition, in the radiation detector described in any of (1) to (7), the High and Low intervals are set by the rise and fall of the exposure time of the frame unit, without including the readout time of the frame unit, and are constant for each measurement.

[0017] (9) The radiation detector described in any of (1) to (8) further comprises a mode switching circuit that switches the setting of the exposure and readout timing between predetermined modes, wherein the control circuit controls the exposure and readout by signal according to the predetermined mode, and the trigger signal generation circuit generates a trigger out signal in which High and Low intervals are defined according to the predetermined mode.

[0018] (10) Also, in the trigger signal generator of the present invention, a trigger signal generator that generates a trigger out signal for external circuits to synchronize with a radiation detector that counts pulses generated when radiation particles are detected by exposure on a per-frame basis, which is connected to the radiation detector, and when one or a series of a predetermined number of frames in which High or Low intervals are set are represented as one unit frame, generates a trigger out signal that specifies the set High and Low intervals.

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

[0020] (12) Also, in the radiation analysis system of the present invention, a radiation analysis system that acquires a radiation intensity distribution for each frame, comprising the trigger signal generator according to (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 Drawings

[0021] [Figure 1] It is a schematic diagram mainly showing the configuration of the radiation detector of the first embodiment. [Figure 2] It is a flowchart mainly showing the operation of the radiation detector of the first embodiment. [Figure 3] It is a timing chart when generating a trigger out signal based on the operation of continuous exposure. [Figure 4] (a) and (b) are schematic diagrams respectively showing the measurement methods of conventional and present invention's tycography. [Figure 5] (a) and (b) are schematic diagrams respectively showing the waveform reproduction when the period of the trigger out signal is long and short with respect to the sampling period of the external synchronization circuit. [Figure 6] This is a timing chart showing the trigger out signal when continuous exposure is not performed. [Figure 7] This is a schematic diagram showing the configuration of the radiation detector in the second embodiment. [Figure 8] This is a timing chart showing the operation of the iterative mode. [Figure 9] This is a timing chart showing the operation of burst mode. [Figure 10] This is a plan view showing the configuration of the radiation analysis system according to the third embodiment. [Figure 11] This is a side view showing the configuration of the radiation analysis system according to the fourth embodiment. [Figure 12] This is a side view showing the configuration of the radiation analysis system according to the fifth embodiment. [Modes for carrying out the invention]

[0022] Next, embodiments of the present invention will be described with reference to the drawings. To facilitate understanding of the description, the same reference numerals are used for identical components in each drawing, and redundant descriptions are omitted.

[0023] [First Embodiment] (Configuration of a radiation detector) Figure 1 is a schematic diagram mainly showing the configuration of the radiation detector 100. The radiation detector 100 is a detector that detects radiation while generating a trigger out signal for synchronization with the external synchronization circuit 210. The radiation detector 100 is preferably a semiconductor detector with a two-dimensional data buffer function. The detection of radiation is most effective when it is X-rays, but is not limited to X-rays, and may also be alpha rays, beta rays, gamma rays, neutron rays, etc. Note that the radiation detector 100 may also 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. The external synchronization circuit 210 can be connected to, for example, a radiation irradiation system for ptychography or a sample support mechanism to correct the radiation irradiation position. The external synchronization circuit 210 can emit a trigger-in signal, allowing the radiation detector 100 to start measurement. For example, the shutter operation signal is the trigger-in signal. The radiation detector 100 and the external synchronization circuit 210 constitute the radiation analysis system 200.

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

[0026] Sensor 110 generates a pulse when radiation particles are detected by exposure. Sensor 110 can detect the intensity of the X-ray beam incident on the light-receiving surface as surface information. Although Figure 1 shows the configuration for a single sensor 110 for convenience, the radiation detector 100 basically has multiple sensors and their respective configurations.

[0027] The detection circuit 120 determines whether the pulse is higher than a reference value when the exposure time is High, and if it is higher, it sends the voltage signal to the counter currently counting among the multiple counters 140a and 140b. The switching circuit 130 switches the counter that counts the voltage signal when it receives a counter switching signal from the control circuit 160. The two counters 140a and 140b each have equivalent functions and can count pulses. Pulses can be counted frame by frame. A frame is the time spent taking one image. For normal exposure and continuous exposure, a frame is identified by the exposure time of one image, but in the 2S mode described later, it is identified by the combined exposure time and readout time. The readout circuit 150 reads the count value from the counter that finished counting immediately before. The memory in the readout circuit 150 stores the read count value.

[0028] The control circuit 160 starts measuring 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. It also causes the trigger signal generation circuit 170 to generate a trigger-out signal when switching between counters that count pulses among multiple counters. The readout circuit 150 reads from the counter 140a that finished counting immediately before, during the timing between generating the trigger-out signal, enabling continuous exposure.

[0029] In this way, the control circuit 160 switches between the counter that counts pulses and the counter that reads the count value from among multiple counters at the timing when it generates a trigger out signal to the trigger signal generation circuit 170, thereby performing continuous exposure. This allows the external synchronization circuit 210 to be synchronized with radiation detection while maintaining the duty cycle of continuous exposure.

[0030] The trigger signal generation circuit 170 generates a trigger out signal that identifies the set High and Low intervals when a predetermined number of frames, or one or a series of frames, with High or Low intervals set, are represented as a single frame unit. In other words, signals corresponding to the rising and falling edges of the High and Low intervals of a single frame unit can be used as trigger out signals. By generating trigger out signals that do not depend on exposure or readout signals in this way, the external synchronization circuit 210 can be synchronized with high accuracy and efficiency for radiation detection. In this case, the exposure time is defined by the trigger out signals of the rising and falling edges of the frame.

[0031] The start or end points of the High and Low intervals can be set to either the rising or falling edge of the exposure time for one frame unit, or to either the rising or falling edge of the readout time for one frame unit. This allows for setting the High and Low intervals according to the application and measurement conditions, and generating a trigger-out signal appropriate for the situation.

[0032] In particular, in continuous exposure mode, one unit frame is one frame, and it is preferable that the trigger signal generation circuit 170 generates a trigger out signal in which High and Low intervals are defined for each rising edge of the exposure time of each frame. This allows radiation detection to be synchronized with an external circuit with a highly efficient duty cycle 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 by control from a PC, for example, in response to instructions from an operator or user. For example, the settings can be changed to generate a trigger-out signal with a waveform matched to the sampling rate of the external synchronization circuit 210. The predetermined modes include, for example, normal mode, continuous exposure mode, iterative mode, and burst mode.

[0034] The control circuit 160 controls exposure and readout by signal according to a predetermined mode, and the trigger signal generation circuit 170 generates a trigger out signal that identifies High and Low intervals according to the predetermined mode. This allows for the generation of a trigger out signal for a predetermined mode that has been switched according to the application and measurement conditions.

[0035] (Operation of the radiation detector) The operation of the radiation detector 100 configured as described above will now be explained. Figure 2 is a flowchart showing the operation of the radiation detector 100. Note that the operation in the continuous exposure mode shown in Figure 2 is just one example, and the operation is not limited to this.

[0036] First, the sample is irradiated with radiation (step S1). When radiation particles that have entered the detection surface are detected by the sensor 110, a pulse is generated. Initially, radiation measurement is started with one counter (step S2), and the trigger signal generation circuit 170 generates a trigger out signal that identifies the High section. The pulse is counted by one of the counters. Then, in response to signals that identify the start and end of the exposure time, the control circuit 160 operates to switch the counter that counts the pulse among the multiple counters 140a and 140b (step S3).

[0037] Simultaneously with the counter switching, the readout circuit 150 begins reading 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 the Low interval (Step S4). The counter that is currently counting maintains its count, and the reading of count data from the counter that finished counting before the counter switching timing is completed (Step S5).

[0038] Next, it is determined whether the measurement is complete or not (step S6). If the measurement is not complete, the process returns to step S3, waits for the High section of the exposure time, switches the counter, and the trigger signal generation circuit 170 generates a trigger out signal that identifies the High or Low section. Steps S3 to S6 are repeated in this manner until the measurement is complete. On the other hand, if it is determined in step 6 that the measurement is complete, the counting is terminated. (Step S7) The measurement is now complete.

[0039] (Continuous exposure timing chart) Next, the trigger-out signal will be explained using a timing chart. Figure 3 is a timing chart showing the operation of continuous exposure. In Figure 3, "Command" indicates the time of instruction to start the measurement. "Exposure" indicates the High and Low intervals of the exposure time. "ReadoutTime" indicates the readout time, which is determined by the ON and OFF states of the readout operation. The radiation detector 100 initially performs a dummy readout operation, then alternately switches the two counters to detect radiation by performing 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 sections of the exposure time. The ENOUT signal shown in this chart is a trigger out signal that identifies the start and end of the exposure time. In continuous exposure mode, after the dummy readout operation, the High sections are continuous without gaps, and the start of the readout before the end of the measurement is the falling edge of the High section. If this is used as a trigger out signal to synchronize 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 in accordance with 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 a single measurement. "ENOUT (Start to Stop)" indicates the High and Low intervals of the measurement time, from the start to the end of the 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 based on the even / odd exposure intervals, it becomes possible to generate a signal for frame position detection.

[0043] The trigger signal generation circuit 170 generates ENOUT signals, which identify the start and end of such frames, as trigger out signals for synchronization with the external synchronization circuit 210, thereby enabling highly efficient and reliable synchronization. The external synchronization circuit 210 detects both the rising and falling edges of the trigger out signal. Note that the meaning of each name and symbol in the timing chart is the same in the following explanation unless otherwise specified.

[0044] (Application to Tychography) Figures 4(a) and 4(b) are schematic diagrams showing the conventional and the present invention's ptychography measurement methods, respectively. In Figures 4(a) and 4(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, while the radiation detector 100 has a trigger signal generation circuit. The irradiation position on the sample S0 can be manipulated using the zone plate 20, enabling ptychography measurement.

[0045] In the example shown in Figure 4(a), if the signals that identify the start and end of the exposure time are used directly as trigger-out signals, continuous exposure is not possible, and a dead time must be deliberately introduced after the exposure interval. If position detection is performed on the rising edge of the trigger-out signal, position detection will not be performed from the first sampling until the seventh sampling, and the high sampling rate cannot be utilized.

[0046] In the example shown in Figure 4(b), a trigger-out signal with alternating High and Low sections is generated for each frame exposure, enabling continuous exposure. Position detection can be performed using the rising and falling edges of the trigger-out signal, and after the first sampling, position detection can be performed at the 4th and 7th samplings, allowing for efficient ptychography measurements. The radiation detector 100 can be used not only for ptychography but also for correcting the positional accuracy of synchrotron radiation applications such as tomography. It is also suitable for applications that require temporal matching between physical quantities such as temperature and exposure.

[0047] (High-speed exposure) In normal mode, continuous exposure is not performed by switching the counter; instead, counting is terminated and reading begins based on a signal from an external device, for example. When performing high-speed exposure in normal mode without switching the counter, short Exposure time If the signals that identify the start and end are used directly as the trigger-out signals, 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 reproductions 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 in Figure 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 exactly as it was. In the example in Figure 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] Thus, for the external synchronization circuit 210 to accurately recognize the trigger-out signal, it is preferable that the period of the trigger-out signal be somewhat long. For this reason, it is preferable to include the readout time of one unit of frame in both the High and Low intervals. This ensures that even if the external circuit cannot detect the signals that determine the start and end of the exposure time due to high-speed exposure, a detectable trigger-out signal can be generated if the readout time is sufficiently long relative to the exposure time.

[0050] In terms of the period length of the trigger-out signal, the High and Low intervals may each be set to the exposure time of two or more frames. The High and Low intervals are set at the rising edge of the exposure time of one unit frame, and it is preferable that they remain constant in the same measurement. A trigger-out signal in which High and Low of a constant length alternate is easy to detect.

[0051] For example, if the synchronization CLK is around 20 kHz, the gap time for the trigger out signal needs to be set to 100 μsec or more. If the signal that identifies the start and end of the exposure time is used directly as the trigger out signal, 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. This would significantly reduce the exposure time for measurements above 5 kfps. By generating a trigger out signal that maintains a High or Low logic of 100 μsec or more, separate from the signal that identifies the start and end of the exposure time, and by using edge detection for the external synchronization circuit 210, it becomes possible to simply increase the frame rate from 5 kHz measurement to 10 kHz measurement.

[0052] By providing a signal that combines the number of frames, it may be possible to measure two applications simultaneously. For example, ptychography measurements could be performed using a trigger-out signal with high and low intervals set for the measurement time of 10 frames, while different measurements are performed for other applications.

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

[0054] For example, at Spring-8, the electron beam generated from the electron gun is accelerated to 1 GeV by a linear accelerator, then introduced into a synchrotron where it is accelerated to 8 GeV. This electron beam is introduced into a storage ring, where synchrotron radiation is generated using bending electromagnets and insertion devices while maintaining an energy of 8 GeV. The generated synchrotron radiation is guided through beamlines to experimental stations located inside and outside the storage ring building. It should be noted that the electron beam does not exist continuously within the ring, but rather in clusters called bunches. With radiation detector 100, the minimum exposure interval can be shortened, making it 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, the radiation detector 100 is effective when the exposure time for a single frame is 1000 μsec or less, as in measurements performed at large synchrotron radiation facilities like this one. Even in such cases, the external synchronization circuit 210 can be synchronized with the trigger out signal, rather than with signals that specify the start and end of the exposure time.

[0056] (High-speed exposure timing chart) 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, exposure and readout periods alternate. In the case of high-speed exposure, the exposure time e is smaller 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 radiation detectors with high frame rates such as XSPA, the High section of the exposure time becomes extremely short, so the signal is never visible, 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 odd-numbered frames to the end of readout, and the Low interval is from the start of exposure of even-numbered frames to the end of readout. Since each of these even / odd intervals includes the readout time, even with high-speed exposure, each interval will not become too short to be detected. In other words, Duty ratio Since this becomes 50%, the above-mentioned problems are eliminated, and synchronization with other circuits becomes relatively easy.

[0058] "EN OUT(even / oddnum)" is a trigger-out signal that identifies 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 instead of just two. By using an ENOUT signal that identifies a time including the exposure times of multiple frames in this way, it is possible to use a trigger-out signal that identifies long High and Low intervals. For example, even if the sampling period of the external synchronization circuit 210 cannot be improved, the frequency of the trigger-out signal can be lowered without sacrificing the measurement frame rate. As a result, the external synchronization circuit 210 can reliably detect the trigger-out signal even with high-speed exposure.

[0059] Furthermore, a processing unit equipped with a processor and memory, such as a PC, may be connected to the above-mentioned radiation analysis system 200, and verification screens such as sine charts of signals that identify the start and end of exposure time and trigger out signals may be displayed upon user request. This allows verification of whether the trigger out signals are being generated as configured. The processing unit may also be located in the cloud.

[0060] [Second Embodiment] (Configuration of a radiation detector) Figure 7 is a schematic diagram showing the configuration of the 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. Because it uses two reference values ​​(Single Threshold), this configuration is also called 2S.

[0061] Detection circuits 120a and 120b determine whether the pulse is higher than their respective reference values, and if it is higher, they send it as a voltage signal to counters 140a and 140b. In the example shown in Figure 7, the reference value of detection circuit 120a is set lower than the reference value of detection circuit 120b.

[0062] Counters 140a and 140b can count pulses. The readout circuit 150 reads and stores the count values ​​obtained by counters 140a and 140b. The switching circuit 145 is controlled by the control circuit 160 and switches between the counters 140a and 140 that are to be read.

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

[0064] Figure 8 is a timing chart showing the operation of the iterative mode. This is suitable when a command is sent once, and then the system is operated only by the trigger out signal. By outputting trigger out signals that specify the High and Low sections every two frames, the external synchronization circuit 210 can be synchronized to the iterative mode exposure. The High and Low sections may be set based on three or more frames instead of just two. In measurements started by receiving a command as described above, the internally generated command functions as a trigger signal to start the detector operation.

[0065] (Burst Mode) The radiation detector 100a may also be set to burst mode. Burst mode is a mode in which multiple counters per pixel are used to expose the image continuously at high speed, acquire multiple frames, and read them out together. For example, if two 14-bit counters are provided per pixel, 14 frames can be measured continuously at high speed using 2 bits per pixel, and read out together using 28 bits per pixel. The exposure time is longer than usual. Even if it's short, it's enough However, the reading time is longer than usual.

[0066] Figure 9 is a timing chart showing the operation of 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 individually. By setting the High and Low sections at the rising and falling edges of the exposure time of a single frame, it becomes possible to perform measurements synchronized with the exposure of each frame individually.

[0067] In this case, the High and Low intervals are constant for each measurement and do not include the frame readout time. This allows for highly efficient synchronization with external circuits, for example, when measuring 14 frames continuously at high speed and reading them all at once in burst mode.

[0068] [Third Embodiment] (Application to single-crystal structure analysis equipment) Figure 10 is a plan view showing the configuration of the radiation analysis system 300. The radiation analysis system 300 is a single-crystal structure analysis device for taking diffracted X-ray images and comprises 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 the sample S0 with X-rays.

[0069] The sample stage 320 and the arm 330 are interconnected 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 located at the end of the arm 330 and its movement around the sample S0 is controlled together with the arm 330. In such a device, the sample stage 320 and the arm 330 can be moved in synchronization with the trigger out signal of the radiation detector 100. Thus, the radiation detector 100 is suitable for angle correction of laboratory X-ray diffractometers.

[0070] Furthermore, for example, exposure can be started by a control signal that drives the arm 330, and the angle of the goniometer can be corrected by comparing the trigger out signal output from the radiation detector 100 with the control signal.

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

[0072] The rotation of the roller 420 moves the belt 425, causing the sample S0 to move in the direction of the arrow in the figure. The control unit 440 controls the belt 425 to move at a constant speed. The radiation detector 100 is located 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 sample S0 together with the belt 425.

[0073] The radiation analysis system 400, having the radiation detector 100 described above, can, for example, move the sample S0 in synchronization with the trigger out signal of the radiation detector 100 and capture an image of the sample S0 by receiving a control signal corresponding to the movement speed. In this case, imaging can be performed with high efficiency, which can increase the product's movement speed and improve the processing efficiency of the process.

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

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

[0076] The trigger signal generator 500 generates a trigger out signal that identifies the High and Low intervals set for a given frame unit, when one frame or a predetermined number of frames in a series are represented as one frame unit. By generating a trigger out signal that is independent of exposure and readout signals, it can synchronize with external circuits with high precision and efficiency. [Explanation of Symbols]

[0077] 10 X-ray source 20-zone plate 100, 100a radiation detector (invention) 110 Sensor 120, 120a, 120b detection circuits 130, 145 switching circuit 140 counter 140a, 140b First and second counters 150 Readout Circuit 160 Control circuits 170 Trigger signal generation circuit 180 Mode Switching Circuit 200 Radiation Analysis Systems 210 External Synchronization Circuit 300 Radiation Analysis Systems 310 X-ray source 320 Sample stage 330 Arm 340 Control Unit 400 Radiation Analysis System 410 X-ray source 420 Laura 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, A sensor that generates a pulse when radiation particles are detected by exposure, A counter is provided that can count the pulses for each frame, A reading circuit that reads out the count value obtained by the aforementioned counter, A control circuit that controls the exposure and readout by a signal, A radiation detector comprising: a trigger signal generation circuit that generates a trigger out signal with alternating High and Low sections for each frame unit, based on the exposure and readout timings, when a predetermined number of frames, one or a series of frames, in which High or Low sections are set, are represented as one unit frame.

2. The radiation detector according to claim 1, characterized in that the start or end point of the High and Low intervals is set at either the rising or falling edge of the exposure time of the one unit frame, or at either the rising or falling edge of the readout time of the one unit frame.

3. The radiation detector according to claim 1 or 2, characterized in that the High and Low intervals each include the readout time of one unit frame.

4. The radiation detector according to claim 3, characterized in that the High and Low intervals are set to either the rising edge of the exposure time of one unit frame and remain constant in the same measurement.

5. The radiation detector according to claim 3, characterized in that the exposure time for one frame is 1000 μsec or less.

6. Multiple counters are provided, The radiation detector according to claim 1 or 2, characterized in that the control circuit switches between a counter that counts the pulses and a counter from which the count value is read out, among a plurality of counters, at the timing of generating the trigger out signal, and performs continuous exposure.

7. The aforementioned unit of frame is a single frame, The radiation detector according to claim 6, characterized in that the trigger signal generation 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.

8. The radiation detector according to claim 1 or 2, characterized in that the High and Low intervals 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.

9. The system further includes a mode switching circuit that switches the exposure and readout timing settings between predetermined modes. The control circuit controls the exposure and readout by signal according to the predetermined mode. The radiation detector according to claim 1 or 2, characterized in that the trigger signal generation circuit generates a trigger out signal in which High and Low intervals are defined according to the predetermined mode.

10. A trigger signal generator that generates a trigger out signal for an external circuit to synchronize with a radiation detector that counts pulses generated when radiation particles are detected by exposure, frame by frame, A trigger signal generator connected to a radiation detector, which generates a trigger out signal that alternately provides High and Low sections for each frame unit, based on the timing of exposure and count reading in the radiation detector, when a predetermined number of frames, one or a series of frames, is represented as one unit frame, and is connected to a radiation detector.

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

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

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