CN114966816A - Digital method, device, device and storage medium for scintillation pulse - Google Patents

Abstract

The invention discloses a method, a device, equipment and a storage medium for digitizing scintillation pulses, wherein the digitizing method comprises the following steps: presetting a plurality of threshold values; comparing the flicker pulse to be processed with a first threshold value in a plurality of threshold values, outputting a jump signal and switching a next threshold value when the amplitude value of the flicker pulse to be processed crosses the first threshold value until all the threshold values are compared; and sampling the jump signals in sequence to obtain corresponding threshold-time pairs when the scintillation pulse to be processed crosses each threshold. The method, the device, the equipment and the storage medium for digitizing the scintillation pulse disclosed by the application effectively reduce hardware resources and logic resources occupied by signal sampling through dynamic switching of the threshold value, and can also improve the accuracy of sampling points and the performance of a sampling system.

Description

Digital method, device, device and storage medium for scintillation pulse

technical field

The present application relates to the field of signal sampling, and in particular, to a method, apparatus, device and storage medium for digitizing scintillation pulses.

Background technique

In a series of applications of high-energy rays, such as positron emission tomography (PET) and radiation detection, high-energy rays, such as gamma rays, are converted into visible light signals by scintillation crystals, which are further converted by photoelectric conversion devices into visible light signals. A scintillation pulse signal, and then a series of application images can be obtained by sampling and processing the scintillation pulse signal. During this process, the digitization quality of the scintillation pulse has a significant impact on the final imaging quality.

In recent years, with the development of digital signal processing technology and methods, the direct digitization of scintillation pulses and the use of software algorithms to replace traditional analog circuits to extract information, such as particle energy deposition information, have great potential for development. Compared with the traditional sampling method at equal time interval, the Multi-Voltage Threshold (MVT) method is a more promising digital processing method for flicker pulses.

As shown in Figure 1, in the MVT sampling method, the time information when the input flicker pulse waveform crosses the set threshold is usually obtained by TDC (time-to-digital converter) technology, so as to invert the flicker pulse according to the corresponding voltage-time information. waveform information. In most cases, multiple voltage thresholds, such as four voltage thresholds, are set, and each voltage threshold corresponds to a channel for subsequent time measurement. ) One of the pins of the comparator is input to the LVDS comparator, and the preset voltage threshold is input to the LVDS comparator through a DAC (digital-to-analog converter), and one of the TDCs in each channel is used to measure the time when the flicker pulse crosses the corresponding threshold To convert, another TDC converts the time the flash pulse is below this threshold, thereby obtaining a series of voltage-time pair information.

In the above structure, TDC is usually implemented by using the carry chain inside the FPGA, which needs to consume certain logic resources inside the FPGA to implement. For example, the flicker pulse waveform input of a single channel corresponds to a 4-channel comparator, which requires 8 input pins and 8-channel TDC measurement modules in the FPGA chip, while an FPGA usually needs to process dozens or hundreds of channels of flicker. For pulse signals, for example, for the most common 12×6 detector array, there are a total of 72 scintillation pulse signal inputs, and the required number of input pins is 576, and the logic resource consumption of a single TDC module is about 2-3K.

Usually a single FPGA chip cannot meet the requirements of pins or logic resources. One solution is to use multiple FPGA chips, such as 2 FPGA chips. However, on the one hand, the resource utilization rate of dual FPGA chips reaches more than 80%, and the measurement accuracy of the TDC module is also restricted due to resource constraints; on the other hand, the high resource utilization rate causes the board to generate more heat. , the working temperature is too high, the measurement accuracy of TDC is affected, and the design difficulty of system heat dissipation is also increased. In addition, using more FPGA chips increases the cost.

SUMMARY OF THE INVENTION

The technical problem to be solved by the embodiments of the present application is how to reduce the resource consumption in the process of digital sampling of the scintillation pulse signal and improve the sampling performance.

In order to solve the above problems, the present application discloses a method, apparatus, device and storage medium for digitizing scintillation pulses.

According to a first aspect of the present application, a method for digitizing scintillation pulses is provided, the digitizing method includes: presetting a plurality of thresholds; When the amplitude of the to-be-processed flicker pulse exceeds the first threshold, a jump signal is output and the next threshold is switched until the comparison of each of the thresholds is completed; the jump signals are sampled in turn to obtain the to-be-to-be The corresponding threshold-time pairs when the scintillation pulse crosses each of the thresholds are processed.

According to some of the embodiments, the threshold is set by a threshold setting device.

According to some of the embodiments, the thresholds include voltage thresholds, current thresholds, energy thresholds, sound intensity thresholds.

According to some of these embodiments, the magnitude of the threshold is set not to exceed the maximum magnitude of the scintillation pulse to be processed.

According to some of these embodiments, the number of thresholds is set to 2-8.

According to some of the embodiments, comparing the to-be-processed scintillation pulse with the threshold includes: comparing the amplitude of the to-be-processed scintillation pulse with the current threshold by a comparison module.

According to some of the embodiments, the plurality of thresholds are set by the same threshold setting device, and the comparison is implemented by the same comparison module.

According to some of these embodiments, the transition signal includes a rising edge or a falling edge that indicates that the flash pulse to be processed crosses the threshold or crosses the threshold.

According to some of these embodiments, the transition signal comprises a rising edge average transition indicating that the pending scintillation pulse crosses the threshold multiple times within the same time window or a falling edge that crosses the threshold multiple times within the same time window average transition.

According to some of these embodiments, the comparison of the first threshold and the other thresholds is done on the rising and falling edges of the pending scintillation pulse, respectively.

According to some of the embodiments, some of the thresholds are switched in descending order.

According to some of the embodiments, sampling the transition signal in sequence includes: acquiring the time corresponding to the rising edge or the falling edge of the transition signal based on a preset sequence, respectively.

According to some of the embodiments, the preset order includes a first order determined from small to large according to part of the thresholds and a second order determined from large to small according to part of the thresholds.

According to some of these embodiments, the sampling is implemented by a circuit comprising a time-to-digital converter that sequentially implements time sampling of all of the transition signals.

According to some of these embodiments, the transition signal includes a status signal for indicating the threshold switching, according to which the next threshold is switched.

According to some of the embodiments, the threshold-time pair includes a transition time obtained by time sampling the transition signal and a corresponding threshold.

According to a second aspect of the present application, a method for digitizing flicker pulses is provided, the digitizing method includes: presetting a plurality of thresholds; When the amplitude of the pulse exceeds the maximum threshold, output a jump signal and switch to the next threshold until all the comparisons of the multiple thresholds are completed; the jump signal is sampled in turn to obtain the to-be-processed flicker pulse that crosses the threshold. The corresponding threshold-time pairs for each threshold.

According to some of the embodiments, the threshold is set by a threshold setting device.

According to some of the embodiments, the thresholds include voltage thresholds, current thresholds, energy thresholds, sound intensity thresholds.

According to some of these embodiments, the magnitude of the threshold is set not to exceed the maximum magnitude of the scintillation pulse to be processed.

According to some of these embodiments, the number of thresholds is set to 2-8.

According to some of the embodiments, comparing the to-be-processed scintillation pulse with the threshold includes: comparing the amplitude of the to-be-processed scintillation pulse with the current threshold by a comparison module.

According to some of the embodiments, the plurality of thresholds are set by the same threshold setting device, and the comparison is implemented by the same comparison module.

According to some of these embodiments, the transition signal includes a rising edge or a falling edge that indicates that the flash pulse to be processed crosses the threshold or crosses the threshold.

According to some of these embodiments, the transition signal comprises a rising edge average transition indicating that the pending scintillation pulse crosses the threshold multiple times within the same time window or a falling edge that crosses the threshold multiple times within the same time window average transition.

According to some of these embodiments, the comparison of the plurality of thresholds is performed on the rising edge or the falling edge of the scintillation pulse to be processed.

According to some of the embodiments, the thresholds are switched in descending order.

According to some of the embodiments, sampling the transition signal in sequence includes: acquiring the time corresponding to the rising edge or the falling edge of the transition signal based on a preset sequence, respectively.

According to some of these embodiments, the sampling is implemented by a circuit comprising a time-to-digital converter that sequentially implements time sampling of the transition signal.

According to some of these embodiments, the transition signal includes a status signal for indicating the threshold switching, according to which the next threshold is switched.

According to some of the embodiments, the threshold-time pair includes a transition time obtained by time sampling the transition signal and a corresponding threshold.

According to a third aspect of the present application, there is provided a method for digitizing scintillation pulses, the digitizing method comprising: presetting a plurality of thresholds; When the amplitude of the flicker pulse exceeds the first threshold, output a jump signal and switch to the maximum threshold; when the amplitude of the flicker pulse to be processed exceeds the maximum threshold, output a jump signal and switch in sequence to the next threshold until all the comparisons of the multiple thresholds are completed; the jump signals are sampled in sequence to obtain the threshold-time pair corresponding to when the to-be-processed flicker pulse crosses each threshold.

According to some of the embodiments, the threshold is set by a threshold setting device.

According to some of the embodiments, the thresholds include voltage thresholds, current thresholds, energy thresholds, sound intensity thresholds.

According to some of these embodiments, the magnitude of the threshold is set not to exceed the maximum magnitude of the scintillation pulse to be processed.

According to some of these embodiments, the number of thresholds is set to 2-8.

According to some of the embodiments, comparing the to-be-processed scintillation pulse with the threshold includes: comparing the amplitude of the to-be-processed scintillation pulse with the current threshold by a comparison module.

According to some of the embodiments, the plurality of thresholds are set by the same threshold setting device, and the comparison is implemented by the same comparison module.

According to some of these embodiments, the transition signal includes a rising edge or a falling edge that indicates that the flash pulse to be processed crosses the threshold or crosses the threshold.

According to some of these embodiments, the transition signal comprises a rising edge average transition indicating that the pending scintillation pulse crosses the threshold multiple times within the same time window or a falling edge that crosses the threshold multiple times within the same time window average transition.

According to some of these embodiments, the comparison of the first threshold is done on the rising edge of the pending scintillation pulse, and the comparison of the remaining thresholds is done on the falling edge of the pending scintillation pulse.

According to some of the embodiments, the digitizing method further includes: after the comparison of the first threshold is completed, comparing the flicker pulse to be processed with a second threshold of the thresholds, the second threshold having an amplitude greater than the The first threshold value, when the amplitude of the to-be-processed flicker pulse exceeds the second threshold value, it is determined as a valid trigger, and it switches to the maximum threshold value.

According to some of the embodiments, the thresholds except the first threshold are switched in descending order.

According to some of the embodiments, sampling the transition signal in sequence includes: acquiring the time corresponding to the rising edge or the falling edge of the transition signal based on a preset sequence, respectively.

According to some of these embodiments, the sampling is implemented by a circuit comprising a time-to-digital converter that sequentially implements time sampling of the transition signal.

According to some of these embodiments, the transition signal includes a status signal for indicating the threshold switching, according to which the next threshold is switched.

According to some of the embodiments, the threshold-time pair includes a transition time obtained by time sampling the transition signal and a corresponding threshold.

According to a fourth aspect of the present application, there is provided a method for digitizing scintillation pulses, the digitizing method comprising: presetting a plurality of thresholds; When the amplitude of the flicker pulse exceeds the first threshold, output a jump signal and switch to the next threshold in sequence; when the amplitude of the flicker pulse to be processed exceeds the maximum threshold, output a jump signal, and the comparison is completed; The hopping signal is sampled, and a threshold-time pair corresponding to when the to-be-processed scintillation pulse crosses each threshold is obtained in combination with the prior information.

According to some of the embodiments, the threshold is set by a threshold setting device.

According to some of the embodiments, the thresholds include voltage thresholds, current thresholds, energy thresholds, sound intensity thresholds.

According to some of these embodiments, the magnitude of the threshold is set not to exceed the maximum magnitude of the scintillation pulse to be processed.

According to some of these embodiments, the number of thresholds is set to 2-8.

According to some of the embodiments, comparing the to-be-processed scintillation pulse with the threshold includes: comparing the amplitude of the to-be-processed scintillation pulse with the current threshold by a comparison module.

According to some of the embodiments, the plurality of thresholds are set by the same threshold setting device, and the comparison is implemented by the same comparison module.

According to some of these embodiments, the transition signal includes a rising edge or a falling edge that indicates that the flash pulse to be processed crosses the threshold or crosses the threshold.

According to some of these embodiments, the transition signal comprises a rising edge average transition indicating that the pending scintillation pulse crosses the threshold multiple times within the same time window or a falling edge that crosses the threshold multiple times within the same time window average transition.

According to some of these embodiments, the comparison of the plurality of thresholds is performed on the rising edge or the falling edge of the scintillation pulse to be processed.

According to some of the embodiments, the digitizing method further includes: after the comparison of the first threshold is completed, comparing the flicker pulse to be processed with a second threshold of the thresholds, the second threshold having an amplitude greater than the The first threshold, when the amplitude of the scintillation pulse to be processed exceeds the second threshold, it is determined as a valid trigger, and the next threshold is switched.

According to some of the embodiments, the plurality of thresholds are switched in ascending order.

According to some of the embodiments, sampling the transition signal in sequence includes: acquiring the time corresponding to the rising edge or the falling edge of the transition signal based on a preset sequence, respectively.

According to some of these embodiments, the sampling is implemented by a circuit comprising a time-to-digital converter that sequentially implements time sampling of the transition signal.

According to some of these embodiments, the transition signal includes a status signal for indicating the threshold switching, according to which the next threshold is switched.

According to some of the embodiments, the prior information is the shape of the scintillation pulse to be processed, and the prior information is obtained through preliminary experiments.

According to some of the embodiments, the threshold-time pair includes a transition time obtained by time sampling the transition signal and a corresponding threshold.

According to a fifth aspect of the present application, there is provided a digitizing device for flicker pulses, the digitizing device comprising: an acquisition module for acquiring flicker pulses to be processed; a threshold switching module for switching multiple preset thresholds; comparing The module is used to compare the to-be-processed flicker pulse with the current threshold of switching, and when the to-be-processed flicker pulse crosses the current threshold, a jump signal is output; a sampling module is used to sequentially measure the jump signal The signal is time-sampled to obtain the corresponding flicker pulse threshold-time pair.

According to some of the embodiments, the threshold switching module includes a digital-to-analog converter for presetting a plurality of the thresholds.

According to some of the embodiments, the threshold switching module is configured to: when the amplitude of the to-be-processed flicker pulse exceeds the first threshold, output a jump signal and switch the next threshold until the multiple The thresholds are all compared.

According to some of the embodiments, the threshold value switching module is configured to: switch the next threshold value according to the status signal for indicating the threshold value switching, until all comparisons of the plurality of threshold values are completed.

According to some of these embodiments, the comparison module includes comparators that respectively compare the pending flash pulses to the current threshold.

According to some of the embodiments, the comparison module is configured to: compare the flicker pulse to be processed with a first threshold value among the plurality of threshold values, and output a value when the amplitude of the flicker pulse to be processed exceeds the first threshold value. The signal is toggled and the next threshold is toggled until all comparisons for each of said thresholds are complete.

According to some of the embodiments, the comparison module is configured to: compare the flicker pulse to be processed with a maximum threshold value among the thresholds, and when the amplitude of the flicker pulse to be processed exceeds the maximum threshold value, output a jump signal and The next threshold is switched until all comparisons of the multiple thresholds are completed.

According to some of the embodiments, the comparison module is configured to: compare the scintillation pulse to be processed with a first threshold value among the thresholds, and output a jump when the amplitude of the scintillation pulse to be processed exceeds the first threshold value signal and switch to the maximum threshold; when the amplitude of the flicker pulse to be processed exceeds the maximum threshold, a jump signal is output and the next threshold is switched in sequence until the comparison of all the thresholds is completed.

According to some of the embodiments, the comparison module is configured to: compare the scintillation pulse to be processed with a first threshold value among the thresholds, and output a jump when the amplitude of the scintillation pulse to be processed exceeds the first threshold value signal and switch to the next threshold in sequence; when the amplitude of the flicker pulse to be processed exceeds the maximum threshold, a jump signal is output, and the comparison is completed.

According to some of these embodiments, the sampling module includes a time-to-digital converter that sequentially implements time sampling of the transition signal.

According to some of the embodiments, the digitizing device further includes a control module configured to receive the status signal generated by the comparison module and control the threshold switching module to switch the next threshold.

According to some of the embodiments, the scintillation pulse threshold-time pair includes a transition time obtained by time sampling for the transition signal and a threshold corresponding to the transition time.

According to some of these embodiments, the digitizing apparatus further includes a data transmission module for transmitting the threshold-time pair data.

According to some of these embodiments, the digitizing apparatus further includes an image reconstruction module that processes the threshold-time pairs according to a preset algorithm.

According to a sixth aspect of the present application, there is provided a digitizing device for flicker pulses, the digitizing device comprising: a plurality of acquisition modules for acquiring flicker pulses to be processed; a plurality of threshold switching modules for switching between preset multiple thresholds; a plurality of parallel comparison modules, each of which is connected to one of the acquisition modules and one of the thresholds, and the comparison modules are used to compare the to-be-processed flicker pulses with the switched current thresholds, When the to-be-processed flicker pulse crosses the current threshold, a jump signal is output; the sampling module is configured to sequentially sample the jump signals from a plurality of comparison modules to obtain the corresponding flicker pulse threshold-time right.

According to some of the embodiments, the threshold switching module includes a digital-to-analog converter for presetting a plurality of the thresholds.

According to some of the embodiments, the threshold switching module is configured to: when the amplitude of the to-be-processed flicker pulse exceeds the first threshold, output a jump signal and switch the next threshold until the multiple The thresholds are all compared.

According to some of the embodiments, the threshold value switching module is configured to: switch the next threshold value according to the status signal for indicating the threshold value switching, until all comparisons of the plurality of threshold values are completed.

According to some of these embodiments, the comparison module includes comparators that respectively compare the pending flash pulses to the current threshold.

According to some of the embodiments, the comparison module is configured to: compare the flicker pulse to be processed with a first threshold value among the plurality of threshold values, and output a value when the amplitude of the flicker pulse to be processed exceeds the first threshold value. The signal is toggled and the next threshold is toggled until all comparisons for each of said thresholds are complete.

According to some of the embodiments, the comparison module is configured to: compare the flicker pulse to be processed with a maximum threshold value among the thresholds, and when the amplitude of the flicker pulse to be processed exceeds the maximum threshold value, output a jump signal and The next threshold is switched until all comparisons of the multiple thresholds are completed.

According to some of the embodiments, the comparison module is configured to: compare the scintillation pulse to be processed with a first threshold value among the thresholds, and output a jump when the amplitude of the scintillation pulse to be processed exceeds the first threshold value signal and switch to the maximum threshold; when the amplitude of the flicker pulse to be processed exceeds the maximum threshold, a jump signal is output and the next threshold is switched in sequence until the comparison of all the thresholds is completed.

According to some of the embodiments, the comparison module is configured to: compare the scintillation pulse to be processed with a first threshold value among the thresholds, and output a jump when the amplitude of the scintillation pulse to be processed exceeds the first threshold value signal and switch to the next threshold in sequence; when the amplitude of the flicker pulse to be processed exceeds the maximum threshold, a jump signal is output, and the comparison is completed.

According to some of these embodiments, the sampling module includes a time-to-digital converter that sequentially implements time sampling of the transition signal.

According to some of the embodiments, the digitizing apparatus further includes a plurality of control modules, the control modules are configured to receive the status signals generated by the corresponding comparison modules and control the corresponding threshold value switching module to switch the next threshold value.

According to some of the embodiments, the scintillation pulse threshold-time pair includes a transition time obtained by time sampling for the transition signal and a threshold corresponding to the transition time.

According to some of these embodiments, the digitizing apparatus further includes a data transmission module for transmitting the threshold-time pair data.

According to some of these embodiments, the digitizing apparatus further includes an image reconstruction module that processes the threshold-time pairs according to a preset algorithm.

According to a seventh aspect of the present application, there is provided a digitizing device, comprising: the digitizing device for flicker pulses as described in any of the above embodiments.

According to an eighth aspect of the present application, there is provided a digitizing device, comprising: a memory, a processor, and a computer program stored on the memory and executable on the processor, the computer program being executed by the processor When executed, the steps of the method as described in any of the above embodiments are implemented.

According to a ninth aspect of the present application, a computer-readable storage medium is provided, and a computer program is stored on the storage medium, and when the computer program is executed by a processor, the steps of the method described in any one of the above embodiments are implemented.

The method, device, device and storage medium for digitizing scintillation pulses disclosed in this application can effectively reduce the hardware resources and logic resources occupied by sampling through dynamic switching of thresholds, and can improve the accuracy of sampling points and improve the performance of the sampling system .

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments described in the present invention. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without any creative effort.

FIG. 1 is an exemplary processing circuit diagram of multi-voltage threshold sampling according to the prior art;

2 is an exemplary flowchart of a method for digitizing scintillation pulses according to some embodiments of the present application;

3 is an exemplary flowchart of a method for digitizing scintillation pulses according to other embodiments of the present application;

4 is an exemplary flowchart of a method for digitizing scintillation pulses according to further embodiments of the present application;

5 is an exemplary flowchart of a method for digitizing scintillation pulses according to other embodiments of the present application;

FIG. 6 is an exemplary schematic diagram of thresholds of scintillation pulses to be processed according to some embodiments of the present application;

FIG. 7 is an exemplary schematic diagram of time sampling of a hopping signal according to some embodiments of the present application;

8 is a schematic diagram illustrating an exemplary relationship between a threshold value, a scintillation pulse to be processed, and a jump signal according to some embodiments of the present application;

FIG. 9 is a schematic diagram illustrating an exemplary relationship between a threshold value, a flicker pulse to be processed and a jump signal according to other embodiments of the present application;

10 is an exemplary block diagram of a data acquisition system of a digitizing device for scintillation pulses according to some embodiments of the present application;

11 is an exemplary block diagram of a data acquisition system of a digitizing device for scintillation pulses according to other embodiments of the present application;

FIG. 12 is a schematic diagram of the connection of a digitizing device for scintillation pulses according to some embodiments of the present application;

FIG. 13 is a schematic diagram of the connection of the digitizing device for scintillation pulses according to other embodiments of the present application; and

FIG. 14 is a schematic diagram of the connection of a digitizing device for scintillation pulses according to some embodiments of the present application.

Detailed ways

In order to make the above objects, features and advantages of the present application more clearly understood, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below.

It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and similar expressions are used herein for illustrative purposes only. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided in order to give a thorough understanding of the embodiments of the present application. However, those skilled in the art will appreciate that the technical solutions of the present application may be practiced without one or more of these specific details, or with other manners, components, materials, devices or operations, and the like. In these instances, well-known structures, methods, devices, implementations, materials, or operations are not shown or described in detail.

The flowcharts shown in the figures are only exemplary illustrations and do not necessarily include all contents and operations/steps, nor do they have to be performed in the order described. For example, some operations/steps can be decomposed, and some operations/steps can be combined or partially combined, so the actual execution order may be changed according to the actual situation.

The terms "first", "second" and the like in the description and claims of the present application and the above drawings are used to distinguish different objects, rather than to describe a specific order. Furthermore, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but optionally also includes unlisted steps or units, or optionally also includes For other steps or units inherent to these processes, methods, products or devices. The terms "and/or" or "and/or" include any and all combinations of one or more of the associated listed items.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this application belongs. The terms used herein in the specification of the application are for the purpose of describing specific embodiments only, and are not intended to limit the application.

Some preferred embodiments of the present application will be described below with reference to the accompanying drawings. It should be noted that the following description is for illustrative purposes and is not intended to limit the scope of protection of the present application.

FIG. 2 is an exemplary flowchart of a method for digitizing scintillation pulses according to some embodiments of the present application. In some embodiments, method 200 of digitizing scintillation pulses may be performed by data acquisition system 1000 . For example, the digitizing method 200 of flicker pulses can be stored in a storage device (such as a built-in storage unit or an external storage device of the data acquisition system 1000 ) in the form of programs or instructions, and when the programs or instructions are executed, the flicker can be realized Pulse digitization method 200 . As shown in FIG. 2, a method 200 of digitizing scintillation pulses may include the following operations.

Step 210, preset N different thresholds, where N is a natural number and N≥2.

In some embodiments, the N thresholds may be used for comparison with the magnitude of the scintillation pulse to be processed. The result of the comparison can be used for time sampling to determine the point in time at which the amplitude of the scintillation pulse to be processed crosses the threshold. After these time points are matched with the corresponding thresholds, they can be used for waveform recovery in subsequent processing (eg, image reconstruction), such as recovering the waveform and/or the waveform area, thereby obtaining the waveform energy value.

In some embodiments, the scintillation pulses to be processed may be acquired by detectors, such as PET detectors, CT detectors, neutron detectors, oil detectors, and these detectors usually include mutually coupled scintillation crystals and photoelectric conversion. devices, in which scintillation crystals are used to convert detected high-energy rays (such as gamma rays, neutron rays, etc.) into visible light signals, and photoelectric conversion devices (such as photomultiplier tube PMT, silicon photomultiplier tube SiPM, etc.) are used for Convert the visible light signal into an electrical signal, and the electrical signal is output in the form of a scintillation pulse signal through an electronic device connected to the photoelectric conversion device. For example, the acquisition module can communicate with the detector to obtain the to-be-processed scintillation pulse. .

In some embodiments, the magnitudes of the thresholds are all within the amplitude of the scintillation pulses to be processed. Referring to FIG. 6 , FIG. 6 is a schematic diagram illustrating an exemplary relationship between threshold voltage and scintillation pulse according to some embodiments of the present application, wherein 610 represents a scintillation pulse, which may be the pending scintillation pulse mentioned in the present application. The waveform of the flicker pulse in the figure shows its characteristic, that is, the rise period is very short, usually only a few nanoseconds, before it can rise to the highest point. The falling period is longer, generally about 200 nanoseconds. 610-1, 610-2, 610-3, 610-4, ..., 610-N represent N different thresholds. It can be seen that the magnitudes of the N thresholds are all within the amplitude of the scintillation pulse. For example, assuming that the amplitude range of the scintillation pulse electrical signal to be processed is 3mV-220mV, if N=4, the four threshold voltages can be 20mV, 40mV, 60mV and 80mV respectively; if N=8, the eight threshold voltages The voltage can take eight values in an arithmetic progression between 10mV and 200mV, respectively.

In the embodiments of the present application, the scintillation pulse signal should be understood as any pulse signal capable of sampling, which is essentially a physical quantity that undergoes a sudden change in a short period of time and then quickly returns to its initial value. The physical quantity has certain characteristics. For example, in some embodiments, the scintillation pulse usually has a rising edge and a falling edge, and the rising edge and the falling edge can be represented by a function model. For example, the scintillation pulse corresponding to a gamma photon usually has a relatively fast rise. and a relatively slow falling edge, the rising edge can be characterized by a linear function, and the falling edge can be characterized by an exponential function. In other embodiments, the waveform of the pulse signal may be represented as a triangular wave, a rectangular wave, a sine wave, a cosine wave, or a wave of some other shape, which will not be repeated here.

In the embodiment of the present application, the manifestation form of the scintillation pulse signal may be an electrical pulse signal, an acoustic pulse signal, a thermal pulse signal, or a pressure wave signal, etc. For example, when the pulse signal is an electrical pulse signal, its corresponding feature may be an electrical pulse signal The voltage and current of the signal; when the pulse signal is an acoustic pulse signal, its corresponding feature may be the sound intensity of the acoustic pulse signal, and so on, which will not be repeated here. Correspondingly, the threshold value can have various forms, for example, when the pulse signal is an electrical pulse signal, the corresponding threshold value can be a voltage threshold value, a current threshold value or an energy threshold value; when the pulse signal is an acoustic pulse signal, its corresponding threshold value can be The corresponding threshold may be a sound intensity threshold, and so on, which will not be repeated here.

It should be understood by those skilled in the art that the scintillation pulse signal in this application can be extended to a continuous signal. Usually, the continuous signal only needs to be regarded as a pulse signal arranged in a certain period. The pulse signal in this application does not serve as a Limits on sampled signals.

In some embodiments, the N thresholds may be set by the same threshold setting device, for example, by selecting one device from multiple digital analog channels to set. After the setting is completed, the threshold setting device can switch the N thresholds in a preset order, and input thresholds of different sizes to the comparator according to the preset order, so that the comparator can receive the currently switched thresholds in real time. and compared with the amplitude of the flash pulse to be processed.

Step 220: Compare the flicker pulse to be processed with the first threshold in the thresholds, when the amplitude of the flicker pulse to be processed exceeds the first threshold, output a jump signal and switch the second threshold in the threshold. threshold.

In some embodiments, comparing the to-be-processed flicker pulse with the threshold refers to synchronously inputting the to-be-processed flicker pulse and the current threshold (such as the Nth threshold) into a comparison module, and the comparison module may compare the current threshold with the threshold according to the size of the current threshold. The amplitudes of the pending flicker pulses are compared.

In some embodiments, the comparison module may be implemented by a circuit including a Low-Voltage Differential Signaling (LVDS) comparator. As an example, the pending scintillation pulse generated by the detector can be input to the p terminal (which may also be referred to as the positive terminal) of the LVDS comparator pin, and the current threshold value can be input to the n terminal of the LVDS comparator pin through the threshold setting device (may also be referred to as the negative terminal), thereby completing the comparison of the pulse amplitude with the current threshold.

In some embodiments, the number of the comparison module and the threshold setting device is one, the switching of multiple different thresholds is realized through the same threshold setting device, and the to-be-processed flicker pulse and multiple thresholds of different sizes are realized through the same comparison module. Comparison. In this way, a single channel can be used to implement the comparison of the scintillation pulse to be processed with multiple thresholds.

It can be known that, generally, for the same threshold whose amplitude is within the range of the maximum amplitude of the scintillation pulse, the scintillation pulse can cross the threshold twice in general. Once during the rising phase of the scintillation pulse, the amplitude of the scintillation pulse crosses and rises above a threshold from low to high. Once during the falling phase of the scintillation pulse, the amplitude of the scintillation pulse crosses and falls below a threshold from high to low. No matter which kind of overshoot is, the comparison module can generate a jump signal during overshoot, and the jump signal reflects the time point when the amplitude of the flicker pulse crosses the threshold. For example, FIG. 6 shows a schematic diagram of multi-voltage threshold sampling. In the rising stage, the flicker pulse 610 will first cross and exceed the threshold voltage 610-1, and then continue to go up and cross and exceed the threshold voltage 610-2. Next, threshold voltage 610-3 and threshold voltage 610-4 are crossed and exceeded. During the falling phase, the blink pulse 610 will first cross and fall below the threshold voltage 610-N. It then continues down, over and below threshold voltage 610-N-1. Next until threshold voltage 610-2 and threshold voltage 610-1 are crossed and below. In the whole process, the blinking pulse 610 may undergo 2N state transitions with respect to the above N threshold voltages.

It should be understood by those skilled in the art that when the threshold is set relatively large, for example, when it is higher than the maximum amplitude of the signal, the amplitude of the flickering pulse cannot always exceed the preset threshold, so the comparison module will not jump; When the threshold is set to be exactly equal to the maximum amplitude of the signal, only one transition occurs in the compare block. Therefore, usually those skilled in the art can reasonably set the size and quantity of the threshold according to limited experiments, so that the interval between the thresholds is reasonable, so that the collected threshold time can more accurately restore the waveform of the scintillation pulse. No longer.

It should also be understood by those skilled in the art that in actual sampling, the waveform of the flicker pulse is not smooth as shown in FIG. The fluctuation rises or the fluctuation falls, and the actual fitted waveform is shown in Figure 6. Therefore, in the actual sampling process, on the rising or falling edge, the waveform may cross the same threshold multiple times within a very short time window, and the actual sampling The average transition time point that crosses the threshold multiple times in a certain time window or time period can be used as the time for crossing the threshold, which is easily realized by those skilled in the art according to the teachings of the present application, and will not be repeated here.

In some embodiments, the comparison module outputs a transition signal after comparing the to-be-processed flicker pulse with the current threshold. The transition signal may indicate a change in state of the pending flash pulse relative to a current threshold (eg, from below the threshold to above and above the threshold or from above to above and below the threshold). The time sampling involved in the subsequent parts of this application may refer to time measurement at the moment corresponding to the state transition. Referring to FIG. 7 , FIG. 7 is an exemplary schematic diagram of a hopping signal according to some embodiments of the present application. The transition signals 710 and 720 - 2 respectively correspond to the scintillation pulse crossing a certain threshold on the rising edge and crossing a certain threshold on the falling edge. The jumping rising edge 712 corresponds to the moment when the rising edge of the pulse to be processed crosses the threshold, and the jumping falling edge 722 corresponds to the moment when the falling edge of the pulse to be processed crosses the threshold.

Step 230, when the amplitude of the scintillation pulse to be processed exceeds the second threshold, output a jump signal and switch to the next threshold until all N thresholds are compared.

For any threshold value, the comparison principle between the amplitude of the scintillation pulse to be processed and the threshold value is the same as that in step 220, the description of step 220 can be referred to, and details are not repeated here.

It should be noted that the switching of different thresholds is realized by the same threshold setting device. After the comparison of the previous threshold is completed, the comparison module can output a feedback signal to the threshold setting device at the same time, the feedback signal can indicate whether the current threshold has jumped, and the feedback signal can be the same as or different from the jump signal. The threshold setting device switches the threshold according to the feedback signal. When the threshold setting device judges that the current threshold has jumped, it will switch to the next threshold in the preset order; when the threshold setting device judges that the current threshold has not jumped, then The current threshold setting is still maintained. For example, in Figure 6, the maximum threshold is 610-N, and the preset sequence of threshold switching is: first, switch from 610-1 to 610-N according to the amplitude of the threshold from small to large. After judging that the current threshold has jumped, then switch to the next threshold in order from small to large; when switching to the maximum threshold 610-N and judging that the current threshold has jumped twice (one from low to high, After crossing from high to low once), it will switch to the next threshold in descending order until all threshold switching is completed.

Step 240: Sequentially sample the transition signals to obtain threshold-time pairs corresponding to when the scintillation pulse to be processed crosses each threshold.

In some embodiments, the sampling may be time digitized sampling for the times corresponding to the rising edge and the falling edge of the transition signal. In this application, the terms "sampling", "time sampling", "time digitized sampling" and "time measurement" can be used interchangeably to refer to the moment when the positions of the rising and falling edges of the transition signal are determined. operate.

In some embodiments, the sampling module may sample the moments corresponding to the rising edge and the falling edge of the transition signal according to a certain sampling sequence. In some embodiments, the sampling module may be implemented by a circuit including a Time-to-Digital Converter (TDC). The sampling module can use TDC to sample the time corresponding to the rising edge or falling edge of the input jump signal, and judge whether the jump point of the rising edge of the jump signal or the jump of the falling edge should be collected according to the feedback signal generated by the comparison module. Time of change. In some embodiments, the sampling module sequentially performs first time sampling on the timing corresponding to the rising edge of the first half of the transition signal based on the first order, obtains time information when the rising edge of the pulse signal crosses the threshold, and sequentially performs sampling based on the second order. The second time sampling is performed at the moment corresponding to the falling edge of the jump signal, and the time information when the falling edge of the pulse signal crosses the threshold is obtained, thereby accurately obtaining the threshold-time pair when the pulse signal crosses each threshold. For the specific description of the time sampling of the hopping signal, reference may be made to the description in FIG. 7 to FIG. 9 of this application, and details are not repeated here.

In some embodiments, the scintillation pulse threshold-time pair may include a hopping time obtained by time sampling for the hopping signal and the amplitude of the threshold corresponding to the hopping signal. For example, for a certain threshold V ₁ , a jump signal can be obtained by comparing it with the scintillation pulse to be processed, and the TDC can measure the time of the jump signal to obtain two time instants, including the time T ₁ corresponding to the position of the rising edge and the falling edge The position of the corresponding time T ₂ . T ₁ and T ₂ may be referred to as transition times, and the flicker pulse threshold-time pair may include (V ₁ , T ₁ ) and (V ₁ , T ₂ ).

In some embodiments, the scintillation pulse threshold-target time pair may be transmitted to other components for further processing. For example, the data processing system may transmit the sampling result to the relevant image processing component of the PET device through wired or wireless communication for subsequent PET image reconstruction.

It should be noted that the above description about each step in FIG. 2 is only for example and illustration, and does not limit the scope of application of the present specification. For those skilled in the art, various modifications and changes can be made to each step in FIG. 2 under the guidance of this specification. However, these corrections and changes are still within the scope of this specification.

In some special applications, such as gamma photon conversion related applications, scintillation crystals are used to convert invisible gamma photons into visible light, and then photoelectric conversion devices are used to convert visible light into scintillation pulse signals, and then a matching sampling method is used to The blinking pulse signal is digitized. The scintillation pulse at this time has a characteristic that the rise time of the pulse is very short, for example, only a few nanoseconds (ns), and the fall time is relatively long, for example, more than 100 nanoseconds. Therefore, when the digitization method in the above embodiment is used to sample the rising edge part, since the rising edge time is very short, it may be inconvenient to switch the threshold value. Therefore, in the following embodiments, the present application discloses a digitization of flicker pulses method that restores the waveform of the scintillation pulse by sampling only on the falling edge. In this embodiment, the method 300 of digitizing scintillation pulses may include the following operations.

Step 310, preset N different thresholds, where N is a natural number and N≥2.

In some embodiments, the settings or descriptions of thresholds and flicker pulses may be the same as those described in the above-mentioned method 200 for digitizing flicker pulses, that is, the descriptions of step 210 in method 200 may be applicable to step 310, and will not be repeated here.

Step 330: Compare the flickering pulse to be processed with the maximum threshold in the thresholds, and when the amplitude of the flickering pulse to be processed exceeds the maximum threshold, output a jump signal and switch the next threshold until all N thresholds are reached. The comparison is done.

In some embodiments, the comparison of the scintillation pulse and the threshold value in step 330 may be the same as that described in step 220 or step 230, and details are not repeated here.

It should be noted here that, when thresholds are usually set, N thresholds are set at intervals of amplitude, and the amplitude of the maximum threshold does not exceed the maximum amplitude of the scintillation pulse signal. In some special waveform applications, such as a flicker pulse with a relatively fast rising edge and a relatively slow falling edge, or a flicker pulse with a symmetrical rising edge and a falling edge, the realization of the threshold switching due to the short duration of the rising edge phase will It is relatively difficult, therefore, by digitizing only the falling edge part or half of the symmetrical part of the scintillation pulse in step 330, and combining with the prior information of the scintillation pulse, the pulse waveform can also be restored. Therefore, in step 330, the initial comparison threshold is first set as the maximum threshold, and when the amplitude of the flicker pulse to be processed exceeds the maximum threshold, it can be considered that the digital sampling at the falling edge stage can be started in descending order of the thresholds . At this time, in the falling edge stage, whenever the amplitude of the flicker pulse crosses and falls below the current threshold, a jump signal will be output, and the jump signal represents the time point when the flicker pulse crosses the current threshold. For a detailed description, refer to the description in the foregoing step 220 or step 230, and details are not repeated here. For falling edge sampling, the order is in descending order according to the magnitude of the threshold.

Step 340: Sequentially sample the transition signals to obtain threshold-time pairs corresponding to when the scintillation pulse to be processed crosses each threshold.

In some embodiments, the sampling may be the same as that described in the foregoing embodiment 240, and details are not repeated here.

It is worth noting that, in this embodiment, the scintillation pulse threshold-target time pair is usually located only on the falling edge of the scintillation pulse. In order to accurately restore the waveform of the scintillation pulse, the waveform needs to be restored by combining the prior information of the scintillation pulse. For example, single-pulse data can usually be pre-collected and restored according to different applications to obtain a priori waveform information of the pulse, which usually has the same waveform, such as the scintillation pulse corresponding to 511keV gamma photon energy in PET applications , its waveform has a relatively fast rising edge and a relatively slow falling edge, usually the rising edge is about 10ns. According to the sampling information of the waveform part of the falling edge and the prior information, the waveform information of the flickering pulse can be more accurately restored. , and further information such as time, position, and energy can be acquired in the subsequent PET image reconstruction, which will not be repeated here.

Further, in order to more accurately determine the starting position of the scintillation pulse waveform, another method for digitizing the scintillation pulse is disclosed in the following embodiments of the present application, which determines the time point at which the scintillation pulse waveform starts to rise and when the scintillation pulse waveform starts to fall. Sampling along the edge restores the waveform of the flicker pulse. In this embodiment, the method 400 of digitizing scintillation pulses may include the following operations.

Step 410, preset N different thresholds, where N is a natural number and N≥2.

In some embodiments, the settings or descriptions of thresholds and flicker pulses may be the same as those described in the above-mentioned method 200 for digitizing flicker pulses, that is, the descriptions of step 210 in method 200 may be applicable to step 310, and will not be repeated here.

Step 420: Compare the flicker pulse to be processed with the first threshold value of the thresholds, and output a jump signal and switch to the maximum threshold value when the amplitude of the flicker pulse to be processed exceeds the first threshold value.

In some embodiments, the first threshold is generally a smaller amplitude among the thresholds, for example, a threshold with the smallest amplitude is defined as the first threshold, or a threshold with the second smallest amplitude is defined as the first threshold, The magnitude of the first threshold is usually greater than the magnitude of the noise in the sampling process. Therefore, when the waveform to be processed crosses and is higher than the first threshold value, it can be considered that the waveform to be processed is in a rising phase. Since the value of the first threshold is relatively low, not only the waveforms of valid flicker pulses, but also the waveforms of some noise signals may cross and be higher than the first threshold. Referring to FIG. 6 , FIG. 6 is a schematic diagram illustrating an exemplary relationship between thresholds and waveforms to be processed according to some embodiments of the present application. As shown in FIG. 6 , the waveform to be processed may include a valid flicker pulse 610 and a noise signal 620 . The maximum amplitude of the noise signal 620 cannot cross and exceed the first threshold 610-1. For subsequent processing steps, a flash pulse 610 that crosses and is above the first threshold 610-1 is a valid trigger.

Further, in some embodiments, if the first threshold is set too large, some signals may be missed, and if the first threshold is set too small, it may cause more noise signals and cause false triggering. Or to maintain a balance between false triggers caused by other signals, the first threshold and the second threshold can be jointly determined in step 420, that is, on the basis of the smaller first threshold, a larger than the first threshold The second threshold, when both the first threshold and the second threshold are crossed, is regarded as an effective trigger for the rising edge of the scintillation pulse signal to be processed. The comparison of the second threshold is exactly the same as the comparison of the first threshold, and details are not repeated here.

The specific sizes of the first threshold and the second threshold can be obtained by those skilled in the art by performing limited experiments according to specific differences of the signals to be sampled, which do not constitute a limitation on the protection scope of the present application. For example, in some embodiments, the second threshold may be greater than the first threshold. In some embodiments, the second threshold may be much larger than the first threshold. Based on the magnitude of the first threshold, the difference between the second threshold and the first threshold may not be less than 100mV. For example, the first threshold voltage may be 5mV and the second threshold voltage may be 105mV. Continuing to refer to FIG. 6, if the waveform to be processed is a valid scintillation pulse such as scintillation pulse 610, the rising phase of the valid scintillation pulse will exceed the second threshold 610-2.

After the signal is determined to be a valid trigger, the threshold is switched to the maximum threshold, thereby completing the sampling of the falling edge portion of the flicker pulse waveform to be processed in the subsequent steps.

Step 430, when the amplitude of the scintillation pulse to be processed exceeds the maximum threshold, output a jump signal and switch other thresholds or the next threshold in sequence until all N thresholds are compared.

In some embodiments, the comparison of the scintillation pulse and the threshold in step 430 may be the same as that described in step 330, and details are not repeated here.

It should be noted here that, when thresholds are usually set, N thresholds are set at intervals of amplitude, and the amplitude of the maximum threshold does not exceed the maximum amplitude of the scintillation pulse signal. In some special waveform applications, such as a PET signal, it usually has a relatively fast rising edge and a relatively slow falling edge. The rising edge phase is only used to determine a valid pulse signal trigger due to its short duration. Step 430 The pulse waveform can be restored by only digitizing the falling edge part and combining with the prior information of the scintillation pulse. Therefore, in step 430, when the amplitude of the scintillation pulse to be processed exceeds the maximum threshold value, it can be considered that the digital sampling in the falling edge phase can be started in descending order of the threshold value. At this time, in the falling edge stage, whenever the amplitude of the flicker pulse crosses and falls below the current threshold, a jump signal will be output, and the jump signal represents the time point when the flicker pulse crosses the current threshold. For details, refer to the description in the foregoing step 230, and details are not repeated here. For falling edge sampling, the order is in descending order according to the magnitude of the threshold.

Step 440: Sequentially sample the transition signals to obtain threshold-time pairs corresponding to when the scintillation pulse to be processed crosses each threshold.

In some embodiments, the sampling may be the same as that described in the foregoing embodiment 340, and details are not repeated here.

It is worth noting that, in this embodiment, the scintillation pulse threshold-target time pair is not only located on the falling edge of the scintillation pulse, but also maintains the time point corresponding to the first threshold and/or the second threshold, combined with the priori of the scintillation pulse information, the starting point information of the first threshold and/or the second threshold, and the sampling data of the falling edge, can more accurately restore the waveform of the flickering pulse, and then obtain information such as time, position, and energy in the subsequent image reconstruction. This will not be repeated here.

Further, in practical sampling applications, quite a lot of flicker pulse signals often appear in the form of symmetrical signals, such as triangular waves, sine waves, etc. For such waveforms, it is often only necessary to collect the information of the rising stage or the falling stage. The test information can accurately restore the waveform of the scintillation pulse. Therefore, the present application also discloses another method for digitizing scintillation pulses, which restores the waveform of scintillation pulses by collecting only half of the waveform signal and combining with prior information. In this embodiment, the method 500 of digitizing scintillation pulses may further include the following operations.

Step 510, preset N different thresholds, where N is a natural number and N≥2.

In some embodiments, the settings or descriptions of thresholds and scintillation pulses may be the same as those described in the above-mentioned digitization method 400 of scintillation pulses, that is, the descriptions of step 410 in method 400 may be applicable to step 510, and will not be repeated here.

Step 520 , compare the flicker pulse to be processed with a first threshold of the thresholds, and when the amplitude of the flicker pulse to be processed exceeds the first threshold, output a jump signal and switch to the next threshold in sequence.

In some embodiments, the setting or description of the first threshold may be the same as that described in the above-mentioned method 400 for digitizing flicker pulses, that is, the description about step 420 in method 400 may be applicable to step 520, and details are not repeated here. .

Further, in some embodiments, if the first threshold is set too large, some signals may be missed, and if the first threshold is set too small, it may cause more noise signals and cause false triggering. Or to maintain a balance between false triggers caused by other signals, the first threshold and the second threshold can be jointly determined in step 420, that is, on the basis of the smaller first threshold, a larger than the first threshold The second threshold, when both the first threshold and the second threshold are crossed, is regarded as an effective trigger for the rising edge of the scintillation pulse signal to be processed. The comparison of the second threshold is exactly the same as the comparison of the first threshold, and details are not repeated here. In some embodiments, the setting or description of the second threshold may be the same as that described in the above-mentioned method 400 for digitizing flicker pulses, that is, the description about step 420 in method 400 may be applicable to step 520, and details are not repeated here. .

After the signal is determined to be a valid trigger, the threshold value is switched to the next threshold value according to the preset order, for example, the switching is performed in order from small to large, so as to complete the sampling of the rising edge part of the flicker pulse waveform to be processed in the subsequent steps. .

Step 530, when the amplitude of the flicker pulse to be processed exceeds the maximum threshold, output a jump signal, and the comparison is completed.

In some embodiments, the comparison between the scintillation pulse and the threshold value in step 530 may be the same as the comparison method described in any of the above embodiments, and details are not repeated here.

It should be noted here that a valid pulse signal trigger can be determined through the above step S520, and the rising edge part can be further digitized through step 530, and the pulse waveform can be restored by combining the prior information of the scintillation pulse (such as a symmetrical waveform) . Therefore, in step 530, when the amplitude of the scintillation pulse to be processed exceeds the maximum threshold, the threshold comparison can be deemed to be completed.

Step 540: Sequentially sample the transition signals, and obtain threshold-time pairs corresponding to when the to-be-processed scintillation pulse crosses each threshold in combination with the prior information.

In some embodiments, the sampling may be the same as that described in any of the above embodiments, and details are not repeated here. In this embodiment, the waveform in the falling edge stage can be regarded as being partially symmetrical with the rising edge during reconstruction, so that the number of sampling points can be reduced and the sampling rate and reconstruction speed can be improved on the premise of ensuring sampling accuracy.

Referring to FIG. 7 , FIG. 7 is an exemplary schematic diagram of a hopping signal according to some embodiments of the present application. The transition signal 710 may be the output signal of the comparator when the flicker pulse crosses the threshold from bottom to top, and the time corresponding to the rising edge 712 may be the time when the flicker pulse crosses the threshold from bottom to top. The transition signal 720 may be the output signal of the comparator when the flicker pulse crosses the threshold from top to bottom, and the time corresponding to the falling edge 722 may be the time when the flicker pulse crosses the threshold from top to bottom. Based on this, the time-to-digital converter can perform time measurement on the transition signal and/or identify the rising edge or falling edge time, and obtain the time when the waveform to be processed crosses each threshold. This time is combined with the corresponding threshold to form a threshold-time pair for subsequent data processing.

FIG. 8 is a schematic diagram illustrating an exemplary relationship among thresholds, waveforms to be processed, and transition signals according to some embodiments of the present application, and correspondingly, reference may be made to the description in the method 400 for digitizing scintillation pulses. As shown in FIG. 8 , the waveform 810 to be processed can be sampled at the rising edge first, that is, the waveform 810 to be processed can be compared with the threshold V1 first. When it is determined that the waveform 810 to be processed has crossed and is higher than the threshold V1, it can be selectively compared with the threshold V2 to determine whether the waveform 810 to be processed is a valid flicker pulse or noise. This can be used to reject false triggers and get a valid rising edge start. After determining that the waveform 810 to be processed is a valid flicker pulse, the waveform 810 to be processed can be compared with the maximum threshold V8. After the time sampling is successful, the comparison with the threshold V7 can be continued. And so on, until the comparison and time sampling of the last threshold V1 are completed. The comparator may output the result of the comparison between the waveform to be processed 810 and the threshold, such as the transition signal 820 shown in FIG. 8 . Transition 820 has multiple rising and falling edges. The rising edge 821' may indicate that the waveform 810 to be processed crosses and is above the threshold V1. Falling edge 828 may indicate that waveform 810 to be processed crosses and falls below threshold V8. Falling edge 827 may indicate that waveform 810 to be processed crosses and falls below threshold V7. And so on. Falling edge 821 may indicate that waveform 810 to be processed crosses and falls below threshold V1. The time corresponding to each rising edge or falling edge is the time when the waveform 810 to be processed transitions (eg, crosses the threshold from top to bottom or bottom to top). The TDC can perform time measurement on the hopping signal to obtain time information at each moment.

FIG. 9 is a schematic diagram illustrating an exemplary relationship among thresholds, waveforms to be processed, and transition signals according to other embodiments of the present application, and correspondingly, reference may be made to the description in the method 200 for digitizing scintillation pulses. As shown in FIG. 9 , the waveform 910 to be processed can be sampled at the rising edge first, that is, the waveform 910 to be processed can be compared with the threshold V1 first. When it is determined that the waveform 910 to be processed has crossed and is higher than the threshold value V1, the threshold value can be directly switched to V2, and then compared with the threshold value V2. And so on, until the comparison of the final threshold V4 is completed. The comparator may output the result of the comparison between the waveform to be processed 910 and the threshold, such as the transition signal 920 shown in FIG. 9 . Transition 920 has multiple rising and falling edges. A rising edge 921 may indicate that the waveform 910 to be processed crosses and is above threshold V1. Rising edge 922 may indicate that waveform 910 to be processed crosses and is above threshold V2. Rising edge 923 may indicate that waveform 910 to be processed crosses and is above threshold V3. Rising edge 924 may indicate that waveform 910 to be processed crosses and is above threshold V4. Since the scintillation pulse 910 is a symmetrical signal, only the rising edge portion of the flicker pulse 910 can be sampled, and the complete waveform information can be obtained by combining with the prior information. If the waveform of the falling edge of the scintillation pulse 910 is a fast falling edge, and the complete waveform information can be predicted in combination with the prior information, those skilled in the art can freely combine and apply according to the description of the above method, which is not repeated here.

In the digitizing method of flicker pulse disclosed in this application, the method of threshold switching can greatly reduce the number of input pins of the data processing chip and the number of time-to-digital conversion modules, which can not only ensure or even improve the signal sampling accuracy, but also greatly reduce the number of The dependence of high-performance data processing chips and time-to-digital conversion modules can be realized by ordinary chips, which is beneficial to improve the later data processing rate and greatly reduce the cost.

FIG. 10 is an exemplary block diagram of an apparatus for digitizing scintillation pulses according to some embodiments of the present application. The data acquisition system in the digital device can realize high-performance scintillation pulse waveform sampling. As shown in FIG. 10 , the data acquisition system 1000 may include an acquisition module 1010 , a threshold switching module 1020 , a comparison module 1030 and a sampling module 1040 .

The obtaining module 1010 can obtain the information of the scintillation pulse to be processed. The scintillation pulse to be processed may be acquired by a detector, such as a PET detector, a CT detector, a neutron detector, and an oil detector, and the acquisition module communicates with the detector to acquire the scintillation pulse to be processed.

The threshold switching module 1020 can acquire multiple thresholds, switch to one of the thresholds in sequence, and send them to the comparison module 1030 . For the setting of multiple thresholds, reference may be made to steps 210 , 310 , 410 , and 510 in the foregoing method embodiments, and details are not described herein again. The threshold switching module 1020 may implement any threshold switching in the foregoing method embodiments.

The comparison module 1030 can compare the pending flicker pulse with the current threshold switched by the threshold switching module 1020, and when the pending flicker pulse crosses and is higher than the current threshold, a jump signal is output, and the threshold switching module 1020 switches accordingly. the next threshold, and the comparison is continued by the comparison module 1030. For the description of the waveform comparison and the transition signal, reference may be made to the description in any of the above method embodiments, and details are not repeated here. The comparison module 1030 may be implemented by a circuit including a Low-Voltage Differential Signaling (LVDS) comparator. Correspondingly, the to-be-processed flicker pulse can be input to the p terminal of the LVDS pin, and the current threshold of the threshold switching module can be input to the n terminal of the LVDS pin, thereby completing the comparison between the flicker pulse and the current threshold.

The sampling module 1040 may sequentially acquire the hopping signal and sample the time of the hopping signal, so as to output corresponding threshold-time pair data. For the sampling module 1040, reference may be made to the description about sampling in the foregoing method embodiments. In some embodiments, the sampling module 1040 may have circuitry including a Time-to-Digital Converter (TDC). In some embodiments, the sampling module 1040 may use an LVDS comparator to implement the comparison between the to-be-processed flicker pulse and the current threshold and obtain a transition signal, and then use TDC to implement time sampling of the transition signal.

In some embodiments, the threshold switching module 1020 can switch the thresholds according to a certain order, the comparison module 1030 performs the comparison operation according to the order, and the sampling module 1040 also obtains the rising edge or falling edge of the transition signal corresponding to the current threshold according to this order. Time point to complete sampling.

FIG. 11 is an exemplary block diagram of an apparatus for digitizing scintillation pulses according to some embodiments of the present application. The data acquisition system in the digital device can realize high-performance scintillation pulse waveform sampling. As shown in FIG. 11 , the data acquisition system 1100 may include an acquisition module 1110 , a threshold switching module 1120 , a comparison module 1130 , a sampling module 1040 and a control module 1150 .

The obtaining module 1110 can obtain the information of the scintillation pulse to be processed.

The threshold switching module 1120 may acquire multiple thresholds, switch to one of the thresholds in sequence, and send them to the comparison module 1130 . For the setting of multiple thresholds, reference may be made to steps 210 , 310 , 410 , and 510 in the foregoing method embodiments, and details are not described herein again. The threshold switching module 1120 may implement switching of any threshold in the foregoing method embodiments.

The comparison module 1130 can compare the pending flicker pulse with the current threshold switched by the threshold switching module 1120, and when the pending flicker pulse crosses and is higher than the current threshold, a jump signal is output, and the threshold switching module 1120 then switches to the next threshold, and the comparison continues by the comparison module 1130. For the description of the waveform comparison and the transition signal, reference may be made to the description in any of the above method embodiments, and details are not repeated here. It should be noted that, in this embodiment, the comparison module 1130 may output a status signal after completing the comparison, and the status signal is used to indicate whether the comparison of the current threshold is completed.

The control module 1150 can receive the status signal generated by the comparison module 1130 and control the threshold switching module 1120 to switch the next threshold. The sequence mentioned in the foregoing embodiment can also be preset by the control module 1150, and the control module 1150 judges the current threshold according to the status signal. The comparison is completed, and the threshold switching module 1120 is immediately instructed to switch to the next threshold according to a preset sequence.

The sampling module 1140 may sequentially acquire the above-mentioned transition signal and/or status signal and sample the time of the transition signal, thereby outputting corresponding threshold-time pair data. For the sampling module 1140, reference may be made to the description about sampling in the foregoing method embodiments. In some embodiments, after the comparison module 1130 completes the comparison operation, it will simultaneously send the transition signal and the status signal to the sampling module, and the sampling module 1140 determines to obtain the rising edge or falling edge of the transition signal corresponding to the current threshold according to the indication of the status signal. time point, the sampling is completed. In some embodiments, the hopping signal may include a status signal synchronously, that is, the time point at which the rising edge or the falling edge of the hopping signal should be collected can be identified according to the hopping signal, which will not be repeated here.

In some embodiments, the time-sampled sampling results may be transmitted to other components for further processing. For example, in the embodiment shown in FIG. 11 , the data acquisition system 1100 may be further connected with the data transmission module 2100 and the image reconstruction module 3100 , wherein the data transmission module 2100 is used to convert the threshold-time finally formed by the data acquisition system 1100 For data packaging, the sampling results can be sent to the image reconstruction module 3100 through wired or wireless communication, and the image reconstruction module 3100 calculates and restores the received data according to a preset algorithm, and completes subsequent image reconstruction. , which can be easily accomplished by those skilled in the art according to the teachings of the present application, and will not be repeated here.

It should be noted that the above description of each step in the accompanying drawings is only for illustration and description, and does not limit the scope of application of the present application. For those skilled in the art, various corrections and changes can be made to each step in the related drawings under the guidance of the present application. However, such corrections and changes are still within the scope of this application.

For other descriptions of the above modules, reference may be made to other parts of this application, for example, FIG. 2 to FIG. 9 .

The digitizing device for flicker pulses disclosed in this application can greatly reduce the number of input pins of the data processing chip and the number of time-to-digital conversion modules by using threshold switching. For example, it can be realized by a single FPGA chip, which can not only guarantee or even improve the Sampling accuracy, and can greatly reduce the dependence on high-performance data processing chips and time-to-digital conversion modules, which can be realized by ordinary chips, which is conducive to improving the later data processing rate and greatly reducing costs.

It should be understood that the system and its modules shown in FIGS. 10-11 can be implemented in various ways. For example, in some embodiments, the system and its modules may be implemented in hardware, software, or a combination of software and hardware. Wherein, the hardware part can be realized by using dedicated logic; the software part can be stored in a memory and executed by a suitable instruction execution system, such as a microprocessor or specially designed hardware. Those skilled in the art will appreciate that the methods and systems described above may be implemented using computer-executable instructions and/or embodied in processor control code, for example on a carrier medium such as a disk, CD or DVD-ROM, such as a read-only memory (firmware) ) or a data carrier such as an optical or electronic signal carrier. The system and its modules of the present application can not only be implemented by hardware circuits such as very large scale integrated circuits or gate arrays, semiconductors such as logic chips, transistors, etc., or programmable hardware devices such as field programmable gate arrays, programmable logic devices, etc. , can also be implemented by, for example, software executed by various types of processors, and can also be implemented by a combination of the above-mentioned hardware circuits and software (eg, firmware).

It should be noted that the above description of the modules is only for the convenience of description, and does not limit the present application to the scope of the illustrated embodiments. It can be understood that for those skilled in the art, after understanding the principle of the system, various modules may be combined arbitrarily, or a subsystem may be formed to connect with other modules without departing from the principle. For example, the data acquisition module and the threshold switching module can be the same comparison module. For another example, the sampling module may include a comparison module at the same time. For another example, each module may share one storage module, and each module may also have its own storage module. Such deformations are all within the protection scope of the present application.

FIG. 12 is an exemplary functional block diagram of an apparatus for digitizing flicker pulses according to some embodiments of the present application. The digitizing device can be implemented based on a Field Programmable Gate Array (Field Programmable Gate Array, FPGA) chip, and is used to realize the digitizing method of the scintillation pulse shown in FIG. 2 to FIG. 5 . As shown in FIG. 12 , Sp can be an input waveform to be processed, and TV can be a threshold switching module for outputting different thresholds. C can be an LVDS comparator to enable threshold comparison to pending flash pulses. In this application, the comparison module can be implemented by C. C can output a comparison result and/or a feedback output. The comparison result may be a transition signal, and the feedback output may be an indication that the flicker pulse to be processed crosses the threshold from top to bottom or crosses the threshold from bottom to top. For example, a 1 indicates that the pending flicker pulse crosses the threshold voltage from top to bottom, and a 0 does not. The result of this comparison can be input to a TDC (time-to-digital converter) for time measurement. In this application, some functions of the sampling module can be implemented by TDC. The feedback output can be input to TCM (Threshold Control Module) to realize the adjustment control of the threshold. For example, the TDC measures the time when the pending flicker pulse crosses the threshold from top to bottom, and the feedback output is 1, then the TCM can control the TV to transmit another threshold to C, and perform the next pending flicker pulse and the new threshold. comparison between. In this application, the threshold adjustment module can be implemented by TCM and TV. DCM is a data transmission module. When the TDC completes the time measurement, the measurement result can be transmitted to the DCM. The DCM can transmit the measurement results to the subsequent processing unit for image reconstruction.

FIG. 13 is an exemplary functional block diagram of a flicker pulse digitizing apparatus according to other embodiments of the present application. The digitizing apparatus can be used to implement the flicker pulse digitizing method shown in FIG. 2 , wherein Sp can be an input pending pulse. To process flicker pulses, TV can be a threshold switching module to output different thresholds. C can be an LVDS comparator to implement threshold comparison with the waveform to be processed. In this application, the comparison module can be implemented by C. C can output a comparison result. The comparison result may be a transition signal. The result of this comparison can be input to a TDC (time-to-digital converter) for time measurement. In this application, the function of the sampling module can be implemented by TDC. DCM is a data transmission module. When the TDC completes the time measurement, the measurement result can be transmitted to the DCM. The DCM can transmit the measurement results to the subsequent processing unit for image reconstruction.

The digitizing device for flicker pulses disclosed in this application can greatly reduce the number of input pins of the data processing chip and the number of time-to-digital conversion modules by using threshold switching. For example, it can be realized by a single FPGA chip, which can not only guarantee or even improve the Sampling accuracy, and can greatly reduce the dependence on high-performance data processing chips and time-to-digital conversion modules, which can be realized by ordinary chips, which is conducive to improving the later data processing rate and greatly reducing costs.

FIG. 14 is an exemplary functional block diagram of an apparatus for digitizing flicker pulses according to other embodiments of the present application. In the embodiment of FIG. 14 , the digitizing device may be based on a Field Programmable Gate Array (FPGA) chip, and may be implemented in a parallel manner of a multi-channel solution. Specifically, as shown in FIG. 14 , Sp can be the input waveform to be processed, and can input two parallel comparators C1 and C2 at the same time; TV1 and TV2 can be two parallel threshold switching modules to output different thresholds , such as outputting two sets of the same threshold, or TV1 outputs the threshold of the rising edge, and TV2 outputs the threshold of the falling edge; C1 and C2 can be LVDS comparators to realize the comparison between the current threshold of the corresponding channel and the flicker pulse to be processed; TCM1 and TCM2 are two sets of parallel threshold control modules, which are used to indicate the switching thresholds of TV1 and TV2 in sequence according to the status signals output by C1 and C2 respectively; the same TDC is connected to the two comparators C1 and C2 respectively, used to respectively Collect the transition signals output by these two comparators. In this embodiment, some functions of the comparison module, the transition signal state signal, and the sampling module may be the same as those described in any of the above-mentioned embodiments. DCM is a data transmission module. When the TDC completes the time measurement, the measurement result can be transmitted to the DCM. The DCM can transmit the measurement results to the subsequent processing unit for image reconstruction.

Through this embodiment, more data points on the rising edge and/or falling edge can be collected, and the more data points the more accurate the restored waveform, which means the time resolution and energy resolution are better, and the solution also saves Compared with the traditional sampling method, the number of channels and pins is more intensive, the accuracy is higher, and the data processing efficiency is higher.

In some embodiments, the present application also provides a digitizing device, which may include the digitizing device mentioned in the above embodiments, and the digitizing device may be used to acquire corresponding scintillation pulse data and perform image reconstruction on it. In a specific example, the device for digitizing scintillation pulses provided by the present application can be applied to positron emission computed tomography (PET). In the PET system, gamma photon data can be collected by using the solution according to the embodiments of the present application. After image reconstruction. In other specific examples of the present application, the method and apparatus for digitizing scintillation pulses, detectors, electronic devices and storage media provided by the present application can be applied to various digital devices, such as CT equipment, MRI equipment, radiation detection equipment, petroleum Detection equipment, weak light detection equipment, SPET equipment, security inspection equipment, gamma camera, X-ray equipment, DR equipment and other equipment using the principle of high-energy ray conversion and other photoelectric conversion application equipment or a combination of the above equipment .

Although not shown, in some embodiments there is also provided a computer-readable storage medium storing a computer program configured to perform the method of any of the embodiments of the present application when executed. The computer program includes each program module/unit constituting the apparatus according to the embodiment of the present application, and the computer program constituted by each program module/unit can realize the function corresponding to each step in the method described in the above embodiment when executed. The computer program can also run on the electronic device as described in the embodiments of the present application.

The basic concepts have been described herein. Obviously, for those skilled in the art, the above detailed disclosure is only an example, and does not constitute a limitation of the present application. Although not explicitly described herein, various modifications, improvements, and corrections to this application may occur to those skilled in the art. Such modifications, improvements, and corrections are suggested in this application, so such modifications, improvements, and corrections still fall within the spirit and scope of the exemplary embodiments of this application.

Meanwhile, the present application uses specific words to describe the embodiments of the present application. Such as "one embodiment," "an embodiment," and/or "some embodiments" means a certain feature, structure, or characteristic associated with at least one embodiment of the present application. Thus, it should be emphasized and noted that two or more references to "an embodiment" or "one embodiment" or "an alternative embodiment" in various places throughout this application are not necessarily referring to the same embodiment . Furthermore, certain features, structures or characteristics of the one or more embodiments of the present application may be combined as appropriate.

Furthermore, those skilled in the art will appreciate that aspects of this application may be illustrated and described in several patentable categories or situations, including any new and useful process, machine, product, or combination of matter, or combinations of them. of any new and useful improvements. Accordingly, various aspects of the present application may be performed entirely by hardware, entirely by software (including firmware, resident software, microcode, etc.), or by a combination of hardware and software. The above hardware or software may be referred to as a "data block", "module", "engine", "unit", "component" or "system". Furthermore, aspects of the present application may be embodied as a computer product comprising computer readable program code embodied in one or more computer readable media.

A computer storage medium may contain a propagated data signal with the computer program code embodied therein, for example, on baseband or as part of a carrier wave. The propagating signal may take a variety of manifestations, including electromagnetic, optical, etc., or a suitable combination. Computer storage media can be any computer-readable media other than computer-readable storage media that can communicate, propagate, or transmit a program for use by coupling to an instruction execution system, apparatus, or device. Program code on a computer storage medium may be transmitted over any suitable medium, including radio, cable, fiber optic cable, RF, or the like, or a combination of any of the foregoing.

The computer program coding required for the operation of the various parts of this application may be written in any one or more programming languages, including object-oriented programming languages such as Java, Scala, Smalltalk, Eiffel, JADE, Emerald, C++, C#, VB.NET, Python etc., conventional procedural programming languages such as C language, Visual Basic, Fortran 2003, Perl, COBOL 2002, PHP, ABAP, dynamic programming languages such as Python, Ruby and Groovy, or other programming languages, etc. The program code may run entirely on the user's computer, or as a stand-alone software package on the user's computer, or partly on the user's computer and partly on a remote computer, or entirely on the remote computer or server. In the latter case, the remote computer can be connected to the user's computer through any network, such as a local area network (LAN) or wide area network (WAN), or to an external computer (eg, through the Internet), or in a cloud computing environment, or as a service Use eg software as a service (SaaS).

Furthermore, unless explicitly stated in the claims, the order of processing elements and sequences described in the present application, the use of numbers and letters, or the use of other names are not intended to limit the order of the procedures and methods of the present application. While the foregoing disclosure discusses by way of various examples some embodiments of the invention that are presently believed to be useful, it is to be understood that such details are for purposes of illustration only and that the appended claims are not limited to the disclosed embodiments, but rather The requirements are intended to cover all modifications and equivalent combinations falling within the spirit and scope of the embodiments of the present application. For example, although the system components described above may be implemented by hardware devices, they may also be implemented by software-only solutions, such as installing the described systems on existing servers or mobile devices.

Similarly, it should be noted that, in order to simplify the expressions disclosed in the present application and thus help the understanding of one or more embodiments of the invention, in the foregoing description of the embodiments of the present application, various features are sometimes combined into one embodiment, in the drawings or descriptions thereof. However, this method of disclosure does not imply that the subject matter of the application requires more features than those mentioned in the claims. Indeed, there are fewer features of an embodiment than all of the features of a single embodiment disclosed above.

Some examples use numbers to describe quantities of ingredients and attributes, it should be understood that such numbers used to describe the examples, in some examples, use the modifiers "about", "approximately" or "substantially" to retouch. Unless stated otherwise, "about", "approximately" or "substantially" means that a variation of ±20% is allowed for the stated number. Accordingly, in some embodiments, the numerical parameters set forth in the specification and claims are approximations that can vary depending upon the desired characteristics of individual embodiments. In some embodiments, the numerical parameters should take into account the specified significant digits and use a general digit reservation method. Notwithstanding that the numerical fields and parameters used in some embodiments of the present application to confirm the breadth of their ranges are approximations, in particular embodiments such numerical values are set as precisely as practicable.

Each patent, patent application, patent application publication, and other material, such as article, book, specification, publication, document, etc., cited in this application is hereby incorporated by reference in its entirety. Application history documents that are inconsistent with or conflict with the content of this application are excluded, as are documents (currently or hereafter appended to this application) that limit the broadest scope of the claims of this application. It should be noted that, if there is any inconsistency or conflict between the descriptions, definitions and/or terms used in the attached materials of this application and the content of this application, the descriptions, definitions and/or terms used in this application shall prevail .

Finally, it should be understood that the embodiments described in the present application are only used to illustrate the principles of the embodiments of the present application. Other variations are also possible within the scope of this application. Accordingly, by way of example and not limitation, alternative configurations of embodiments of the present application may be considered consistent with the teachings of the present application. Accordingly, the embodiments of the present application are not limited to those explicitly introduced and described in the present application.

Claims (95)

1. A method for digitizing scintillation pulses, the method comprising:

presetting a plurality of threshold values;

comparing the flicker pulse to be processed with a first threshold value in the plurality of threshold values, and outputting a jump signal and switching a next threshold value when the amplitude of the flicker pulse to be processed crosses the first threshold value until all the threshold values are compared; and

and sampling the jump signals in sequence to acquire corresponding threshold-time pairs when the scintillation pulse to be processed crosses each threshold.

2. The method of claim 1, wherein the threshold is set by a threshold setting device.

3. The method of claim 1, wherein the threshold comprises a voltage threshold, a current threshold, an energy threshold, and an intensity threshold.

4. The method of claim 1, wherein the threshold value is set to a magnitude not exceeding a maximum amplitude of the scintillation pulse to be processed.

5. The method of claim 1, wherein the number of the threshold values is set to 2-8.

6. The method of any one of claims 1 to 5, wherein comparing the scintillation pulse to be processed with the threshold value comprises:

and comparing the amplitude of the scintillation pulse to be processed with the current threshold value through a comparison module.

7. The method of claim 6, wherein said plurality of thresholds are set by a same threshold setting device, and said comparison is performed by a same comparing module.

8. The method of claim 1, wherein the transition signal comprises a rising edge indicating that the scintillation pulse to be processed crosses the threshold or a falling edge indicating that the scintillation pulse to be processed crosses the threshold.

9. The method of claim 1, wherein the transition signal comprises a mean transition of rising edges indicating a plurality of crossings of the threshold value by the glitch pulse to be processed within a same time window or a mean transition of falling edges indicating a plurality of crossings of the threshold value within a same time window.

10. The method according to claim 1, characterized in that the comparison between said first threshold and the other said thresholds is done on the rising and falling edges, respectively, of the scintillation pulse to be processed.

11. The method of claim 1, wherein the threshold values are switched in descending order.

12. The method of claim 1, wherein sequentially sampling the transition signal comprises:

and respectively acquiring the time corresponding to the rising edge or the falling edge of the jump signal based on a preset sequence.

13. The method of claim 12, wherein the predetermined sequence comprises a first sequence determined from small to large according to a portion of the threshold value and a second sequence determined from large to small according to a portion of the threshold value.

14. The method of claim 1, wherein said sampling is performed by a circuit comprising a time-to-digital converter that sequentially performs time sampling of all of said transition signals.

15. The method of claim 1, wherein the transition signal comprises a status signal for indicating the threshold switching, and the next threshold is switched according to the status signal.

16. The method of claim 1, wherein the threshold-time pair comprises a transition time obtained by time sampling the transition signal and a corresponding threshold.

17. A method for digitizing scintillation pulses, the method comprising:

presetting a plurality of threshold values;

comparing the flicker pulse to be processed with the maximum threshold value in the threshold values, and outputting a jump signal and switching to the next threshold value when the amplitude of the flicker pulse to be processed exceeds the maximum threshold value until the comparison of the threshold values is completed;

and sampling the jump signal in sequence to obtain corresponding threshold-time pairs when the scintillation pulse to be processed crosses each threshold.

18. The method of claim 17, wherein the threshold is set by a threshold setting device.

19. The method of claim 17, wherein the threshold comprises a voltage threshold, a current threshold, an energy threshold, and a sound intensity threshold.

20. The method of claim 17, wherein the threshold value is set to a magnitude not exceeding a maximum amplitude of the scintillation pulse to be processed.

21. The method of digitizing scintillation pulses of claim 17, wherein the number of thresholds is set to 2-8.

22. The method of digitizing scintillation pulses according to any of claims 17 to 21, characterized in that comparing the scintillation pulses to be processed with the threshold value comprises:

and comparing the amplitude of the scintillation pulse to be processed with the current threshold value through a comparison module.

23. The method of claim 22, wherein said plurality of thresholds are set by a same threshold setting device, and said comparison is performed by a same comparing module.

24. The method of claim 17, wherein the transition signal comprises a rising edge indicating that the scintillation pulse to be processed crosses the threshold or a falling edge indicating that the scintillation pulse to be processed crosses the threshold.

25. The method of claim 17, wherein the transition signal comprises a mean transition of rising edges indicating a plurality of crossings of the threshold value by the glitch pulse to be processed within a same time window or a mean transition of falling edges indicating a plurality of crossings of the threshold value within a same time window.

26. The method of claim 17, wherein the comparing of the plurality of thresholds is performed on a rising edge or a falling edge of the scintillation pulse to be processed.

27. The method of claim 17, wherein the threshold is switched in order of magnitude.

28. The method of claim 17, wherein sampling the transition signal sequentially comprises:

and respectively acquiring the time corresponding to the rising edge or the falling edge of the jump signal based on a preset sequence.

29. The method of claim 17, wherein the sampling is performed by a circuit comprising a time-to-digital converter that sequentially performs time sampling of the transition signal.

30. The method of claim 17, wherein the transition signal comprises a status signal for indicating the threshold switching, and wherein the next threshold is switched according to the status signal.

31. The method of claim 17, wherein the threshold-time pair comprises a transition time obtained by time sampling the transition signal and a corresponding threshold value.

32. A method for digitizing scintillation pulses, the method comprising:

presetting a plurality of threshold values;

comparing the flicker pulse to be processed with a first threshold value in the threshold values, and outputting a jump signal and switching to a maximum threshold value when the amplitude of the flicker pulse to be processed crosses the first threshold value;

when the amplitude of the scintillation pulse to be processed exceeds the maximum threshold, outputting a jump signal and switching a next threshold in sequence until the comparison of the thresholds is completed;

and sampling the jump signal in sequence to obtain corresponding threshold-time pairs when the scintillation pulse to be processed crosses each threshold.

33. The method of claim 32, wherein the threshold is set by a threshold setting device.

34. The method of claim 32, wherein the threshold comprises a voltage threshold, a current threshold, an energy threshold, and a sound intensity threshold.

35. The method of claim 32, wherein the threshold value is set to a magnitude not exceeding a maximum amplitude of the scintillation pulse to be processed.

36. The method of digitizing scintillation pulses of claim 32, wherein the number of thresholds is set to 2-8.

37. The method of any one of claims 32 to 36, wherein comparing the scintillation pulse to be processed with the threshold value comprises:

and comparing the amplitude of the scintillation pulse to be processed with the current threshold value through a comparison module.

38. The method of claim 37, wherein said plurality of thresholds are set by a same threshold setting device, and said comparison is performed by a same comparing module.

39. The method of claim 32, wherein the transition signal comprises a rising edge indicating that the scintillation pulse to be processed crosses the threshold or a falling edge indicating that the scintillation pulse to be processed crosses the threshold.

40. The method of claim 32, wherein the transition signal comprises a mean transition of rising edges indicating a plurality of crossings of the threshold value by the glitch pulse to be processed within a same time window or a mean transition of falling edges indicating a plurality of crossings of the threshold value within a same time window.

41. The method of claim 32, wherein the comparison of the first threshold is performed at a rising edge of the scintillation pulse to be processed, and the comparison of the remaining thresholds is performed at a falling edge of the scintillation pulse to be processed.

42. The method of digitizing scintillation pulses according to claim 41, further comprising:

and after the comparison of the first threshold is finished, comparing the flicker pulse to be processed with a second threshold in the thresholds, wherein the amplitude of the second threshold is larger than the first threshold, and when the amplitude of the flicker pulse to be processed exceeds the second threshold, determining the flicker pulse to be effectively triggered and switching to the maximum threshold.

43. The method of claim 32, wherein the thresholds are switched from large to small except the first threshold.

44. The method of claim 32, wherein sequentially sampling the transition signals comprises:

and respectively acquiring the time corresponding to the rising edge or the falling edge of the jump signal based on a preset sequence.

45. The method of claim 32, wherein said sampling is performed by a circuit comprising a time-to-digital converter that sequentially performs time sampling of said transition signal.

46. The method of claim 32, wherein the transition signal comprises a status signal for indicating the threshold switching, and the next threshold is switched according to the status signal.

47. The method of claim 32, wherein the threshold-time pair comprises a transition time obtained by time sampling the transition signal and a corresponding threshold.

48. A method for digitizing scintillation pulses, the method comprising:

presetting a plurality of threshold values;

comparing the flicker pulse to be processed with a first threshold value in the threshold values, and outputting a jump signal and sequentially switching to the next threshold value when the amplitude of the flicker pulse to be processed crosses the first threshold value;

when the amplitude of the scintillation pulse to be processed exceeds the maximum threshold value, outputting a jump signal, and finishing comparison;

and sampling the jump signal in sequence, and acquiring corresponding threshold-time pairs when the scintillation pulse to be processed crosses each threshold by combining prior information.

49. The method of claim 48, wherein said threshold is set by a threshold setting device.

50. The method of claim 48, wherein the threshold comprises a voltage threshold, a current threshold, an energy threshold, and a sound intensity threshold.

51. The method of claim 48, wherein the threshold is set to a magnitude not exceeding a maximum amplitude of the scintillation pulse to be processed.

52. The method of claim 48, wherein the number of said threshold values is set to 2-8.

53. The method of digitizing scintillation pulses according to any one of claims 48 to 52, wherein comparing the scintillation pulses to be processed with the threshold value comprises:

and comparing the amplitude of the scintillation pulse to be processed with the current threshold value through a comparison module.

54. The method of claim 53, wherein said plurality of thresholds are set by a same threshold setting device, and said comparison is performed by a same comparing module.

55. The method of claim 48, wherein the transition signal comprises a rising edge indicating that the scintillation pulse to be processed crosses the threshold or a falling edge indicating that the scintillation pulse to be processed crosses the threshold.

56. The method of claim 48, wherein the transition signal comprises a mean transition of rising edges indicating a plurality of crossings of the threshold value by the scintillation pulse to be processed within a same time window or a mean transition of falling edges indicating a plurality of crossings of the threshold value within a same time window.

57. The method of claim 48, wherein the comparing of the plurality of thresholds is performed on a rising edge or a falling edge of the scintillation pulse to be processed.

58. The method of digitizing scintillation pulses according to claim 48, further comprising:

and after the comparison of the first threshold is finished, comparing the flicker pulse to be processed with a second threshold in the thresholds, wherein the amplitude of the second threshold is larger than the first threshold, when the amplitude of the flicker pulse to be processed exceeds the second threshold, determining that the flicker pulse to be processed is effectively triggered, and switching to the next threshold.

59. The method of digitizing scintillation pulses according to claim 48, characterized in that the plurality of thresholds are switched in order from small to large.

60. The method of claim 48, wherein sequentially sampling the transition signals comprises:

and respectively acquiring the time corresponding to the rising edge or the falling edge of the jump signal based on a preset sequence.

61. The method of claim 48, wherein said sampling is performed by a circuit comprising a time-to-digital converter that sequentially performs time sampling of said transition signal.

62. The method of claim 48, wherein said transition signal comprises a status signal for indicating switching of said threshold, and wherein a next threshold is switched according to said status signal.

63. The method of claim 48, wherein the a priori information is a shape of the scintillation pulse to be processed, and the a priori information is obtained through a preliminary experiment.

64. The method of claim 48, wherein said threshold-time pair comprises a transition time obtained by time sampling said transition signal and a corresponding threshold value.

65. An apparatus for digitizing scintillation pulses, the apparatus comprising:

the acquisition module is used for acquiring scintillation pulses to be processed;

the threshold switching module is used for switching a plurality of preset thresholds;

the comparison module is used for comparing the flicker pulse to be processed with the switched current threshold value and outputting a jump signal when the flicker pulse to be processed crosses the current threshold value;

and the sampling module is used for sequentially carrying out time sampling on the jump signals and acquiring corresponding scintillation pulse threshold value-time pairs.

66. The apparatus for digitizing scintillation pulses according to claim 65, wherein the threshold switching module comprises a digital-to-analog converter for presetting a plurality of the thresholds.

67. The apparatus for digitizing scintillation pulses according to claim 65, wherein the threshold switching module is configured to:

and when the amplitude of the scintillation pulse to be processed crosses the first threshold, outputting a jump signal and switching to the next threshold until the comparison of all the thresholds is completed.

68. The apparatus for digitizing scintillation pulses according to claim 65, wherein the threshold switching module is configured to:

and switching the next threshold according to a state signal for indicating the threshold switching until all the thresholds are compared.

69. The apparatus for digitizing scintillation pulses according to claim 65, wherein said comparison module comprises comparators for comparing said scintillation pulses to be processed with said current threshold values, respectively.

70. The apparatus for digitizing scintillation pulses according to claim 65, wherein the comparison module is configured to:

and comparing the flicker pulse to be processed with a first threshold value in the plurality of threshold values, outputting a jump signal and switching a next threshold value when the amplitude of the flicker pulse to be processed crosses the first threshold value until all the threshold values are compared.

71. The apparatus for digitizing scintillation pulses according to claim 65, wherein the comparison module is configured to:

and comparing the flicker pulse to be processed with the maximum threshold value in the threshold values, outputting a jump signal and switching the next threshold value when the amplitude of the flicker pulse to be processed exceeds the maximum threshold value until the comparison of the threshold values is completed.

72. The apparatus for digitizing scintillation pulses according to claim 65, wherein the comparison module is configured to:

comparing the flicker pulse to be processed with a first threshold value in the threshold values, and outputting a jump signal and switching to a maximum threshold value when the amplitude of the flicker pulse to be processed crosses the first threshold value; and when the amplitude of the scintillation pulse to be processed exceeds the maximum threshold, outputting a jump signal and switching a next threshold in sequence until the comparison of all the thresholds is completed.

73. The apparatus for digitizing scintillation pulses of claim 65, wherein the comparison module is configured to:

comparing the flicker pulse to be processed with a first threshold value in the threshold values, and outputting a jump signal and sequentially switching to the next threshold value when the amplitude of the flicker pulse to be processed crosses the first threshold value; and when the amplitude of the scintillation pulse to be processed exceeds the maximum threshold value, outputting a jump signal, and finishing comparison.

74. The apparatus for digitizing scintillation pulses according to claim 65, wherein said sampling module comprises a time-to-digital converter that sequentially performs time sampling of said transition signal.

75. The apparatus for digitizing scintillation pulses according to claim 65, further comprising a control module configured to receive the status signal generated by the comparison module and control the threshold switching module to switch to a next threshold.

76. The apparatus for digitizing scintillation pulses according to claim 65, wherein the scintillation pulse threshold-time pair comprises a transition time obtained by time sampling the transition signal and a threshold value corresponding to the transition time.

77. The apparatus for digitizing scintillation pulses according to claim 65, further comprising a data transmission module for transmitting said threshold-time pair data.

78. The apparatus for digitizing scintillation pulses according to claim 65 or 77, further comprising an image reconstruction module for processing the threshold-time pairs according to a preset algorithm.

79. An apparatus for digitizing scintillation pulses, the apparatus comprising:

the acquisition modules are used for acquiring scintillation pulses to be processed;

the threshold switching module is used for switching a plurality of preset thresholds;

the comparison modules are connected with the acquisition module and a threshold value in a switching mode, and used for comparing the flicker pulse to be processed with the switched current threshold value and outputting a jump signal when the flicker pulse to be processed crosses the current threshold value;

and the sampling module is used for sequentially carrying out time sampling on the jump signals from the plurality of comparison modules to obtain corresponding flicker pulse threshold-time pairs.

80. The apparatus for digitizing scintillation pulses according to claim 79, wherein the threshold switching module comprises a digital-to-analog converter for presetting a plurality of the thresholds.

81. The apparatus for digitizing scintillation pulses according to claim 79, wherein the threshold switching module is configured to:

and when the amplitude of the flicker pulse to be processed crosses the first threshold value, outputting a jump signal and switching to the next threshold value until the comparison of all the threshold values is completed.

82. The apparatus for digitizing scintillation pulses according to claim 79, wherein the threshold switching module is configured to:

and switching the next threshold according to a state signal for indicating the threshold switching until all the thresholds are compared.

83. The apparatus for digitizing scintillation pulses of claim 79, wherein the comparing module comprises comparators for comparing the scintillation pulses to be processed with the current threshold respectively.

84. The apparatus for digitizing scintillation pulses according to claim 79, wherein the comparison module is configured to:

and comparing the flicker pulse to be processed with a first threshold value in the plurality of threshold values, outputting a jump signal and switching a next threshold value when the amplitude of the flicker pulse to be processed crosses the first threshold value until all the threshold values are compared.

85. The apparatus for digitizing scintillation pulses according to claim 79, wherein the comparison module is configured to:

and comparing the flicker pulse to be processed with the maximum threshold value in the threshold values, outputting a jump signal and switching the next threshold value when the amplitude of the flicker pulse to be processed exceeds the maximum threshold value until the comparison of the threshold values is completed.

86. The apparatus for digitizing scintillation pulses according to claim 79, wherein the comparison module is configured to:

comparing the flicker pulse to be processed with a first threshold value in the threshold values, and outputting a jump signal and switching to a maximum threshold value when the amplitude of the flicker pulse to be processed crosses the first threshold value; and when the amplitude of the scintillation pulse to be processed exceeds the maximum threshold, outputting a jump signal and switching a next threshold in sequence until the comparison of all the thresholds is completed.

87. The apparatus for digitizing scintillation pulses according to claim 79, wherein the comparison module is configured to:

comparing the flicker pulse to be processed with a first threshold value in the threshold values, and outputting a jump signal and sequentially switching to the next threshold value when the amplitude of the flicker pulse to be processed crosses the first threshold value; and when the amplitude of the scintillation pulse to be processed exceeds the maximum threshold value, outputting a jump signal, and finishing comparison.

88. The apparatus for digitizing scintillation pulses according to claim 79, wherein said sampling module comprises a time-to-digital converter that sequentially performs time sampling of said transition signal.

89. The apparatus for digitizing scintillation pulses according to claim 79, further comprising a plurality of control blocks for receiving the status signal generated by the corresponding comparing block and controlling the corresponding threshold switching block to switch to a next threshold.

90. The apparatus for digitizing scintillation pulses according to claim 79, wherein the scintillation pulse threshold-time pair comprises a transition time obtained by time sampling the transition signal and a threshold value corresponding to the transition time.

91. The apparatus for digitizing scintillation pulses according to claim 79, further comprising a data transmission module for transmitting said threshold-time pair data.

92. The apparatus for digitizing scintillation pulses according to claim 79 or 91, further comprising an image reconstruction module for processing the threshold-time pairs according to a preset algorithm.

93. A digitizing apparatus, comprising: apparatus for digitizing scintillation pulses as claimed in any one of claims 65 to 78.

94. A digitizing apparatus, comprising: memory, processor and computer program stored on the memory and executable on the processor, which when executed by the processor implements the steps of the method of any one of claims 1 to 64.

95. A computer-readable storage medium, characterized in that a computer program is stored on the storage medium, which computer program, when being executed by a processor, carries out the steps of a method according to any one of claims 1 to 64.

Images