WO2023284606A1

WO2023284606A1 - Radiation imaging system and method

Info

Publication number: WO2023284606A1
Application number: PCT/CN2022/104091
Authority: WO
Inventors: 陈志强; 李元景; 孙尚民; 李荐民; 梁松; 刘必成; 党永乐; 宗春光; 邹湘; 于昊; 赵博震
Original assignee: 同方威视技术股份有限公司; 清华大学
Priority date: 2021-07-12
Filing date: 2022-07-06
Publication date: 2023-01-19
Also published as: CN113281357A

Abstract

The present invention relates to the technical field of radiation detection, and provides a radiation imaging system and method. The radiation imaging system of the present invention comprises: a photodiode detector, configured to receive rays from a ray source and generate a first detection signal; a first imaging device, connected to the photodiode detector and configured to generate first imaging data according to the first detection signal; a counting detector, located on the side of the photodiode detector away from a ray receiving surface and configured to receive rays penetrating through the photodiode detector and generate a second detection signal; a counting imaging device, connected to the counting detector and configured to generate counting imaging data according to the second detection signal; and an image fusion apparatus, configured to obtain a first fusion image according to the first imaging data and the counting imaging data, so as to improve the radiation detection quality.

Description

Radiation Imaging Systems and Methods

Cross References to Related Applications

This application is based on the application with CN application number 202110781545.0 and the application date is July 12, 2021, and claims its priority. The disclosure content of this CN application is hereby incorporated into this application as a whole.

technical field

The present disclosure relates to the technical field of radiation detection, in particular to a radiation imaging system and method.

Background technique

Compared with PMT (Photomultiplier Tube, photomultiplier tube), SiPM (Silicon Photomultiplier, silicon photomultiplier tube) has excellent performance in many aspects such as small size, low working voltage and high measurement accuracy in realizing the photon-to-charge conversion of the scintillation detector. .

SiPM detectors have good detection efficiency for extremely weak light, and can be used in high-throughput and high-energy X-ray imaging systems. They have good image effects and are suitable for counting imaging.

Contents of the invention

It is an object of the present disclosure to improve radiographic imaging quality.

According to an aspect of some embodiments of the present disclosure, a radiation imaging system is provided, including: a photodiode detector configured to receive radiation from a radiation source and generate a first detection signal; a first imaging device and a photodiode The detector is connected and configured to generate first imaging data according to the first detection signal; the counting detector is located on the side of the photodiode detector away from the ray receiving surface, and is configured to receive the ray passing through the photodiode detector to generate The second detection signal; the counting imaging device, connected to the counting detector, configured to generate counting imaging data according to the second detection signal; and the image fusion device, configured to obtain the first fusion according to the first imaging data and the counting imaging data image.

In some embodiments, the counting imaging device includes: a counting amplifier configured to output a counting detection signal according to the second detection signal and a predetermined counting amplification factor; a comparator connected to the counting amplifier and configured to compare the counting detection signal with a predetermined counting threshold comparison, outputting a counting signal to the counter when the counting detection signal is greater than a predetermined counting threshold; the counter, configured to count the counting signal output by the comparator, and acquire counting data; and the counting imaging device, configured to generate counting data according to the counting data Count imaging data.

In some embodiments, the comparator is configured to compare the counting detection signal with a plurality of predetermined counting thresholds, and output a counting signal corresponding to each predetermined counting threshold respectively; the counter is configured to count the counting signals corresponding to each predetermined counting threshold , acquiring counting data corresponding to each predetermined counting threshold; the counting imaging device is configured to respectively generate counting imaging data corresponding to each predetermined counting threshold according to the counting data.

In some embodiments, the radiation imaging system further includes: a material identification device configured to identify the material type of the measured object through which the rays pass through according to the count imaging data corresponding to each predetermined count threshold, and output material type information.

In some embodiments, the radiation imaging system further includes an integral imaging device configured to generate integral imaging data according to the second detection signal; the image fusion device is further configured to obtain a second fusion image according to the count imaging data and the integral imaging data.

In some embodiments, the image fusion device is further configured to acquire a third fused image according to the integral imaging data, the first imaging data and the count imaging data.

In some embodiments, the image fusion device is further configured to acquire a fourth fused image according to the integral imaging data and the first imaging data.

In some embodiments, the integral imaging device includes: an integrator configured to perform an integral operation according to the second detection signal, and output integral data; an analog-to-digital converter configured to generate an integral digital signal according to the integral data; and an integral imaging device , configured to generate integrated imaging data from the integrated digital signal.

In some embodiments, the radiation imaging system further includes: a primary amplifier, located between the counting detector and the counting imaging device, and between the counting detector and the integral imaging device, configured to amplify the second detection signal according to a predetermined integral amplification factor, An integrated detection signal is generated and output to a counting imaging device and an integral imaging device.

In some embodiments, the counting detector includes a SiPM detector or a CZT (Cadmium Zinc Telluride, Cadmium Zinc Telluride) detector.

According to an aspect of some embodiments of the present disclosure, a radiation imaging method is provided, including: receiving radiation from a radiation source through a photodiode detector, generating a first detection signal, and generating first imaging data according to the first detection signal; The counting detector receives the rays passing through the photodiode detector, generates a second detection signal, and generates counting imaging data according to the second detection signal; and acquires a first fusion image according to the first imaging data and the counting imaging data.

In some embodiments, generating the count imaging data according to the second detection signal includes: obtaining the count detection signal according to the second detection signal and a predetermined count amplification factor; comparing the count detection signal with a predetermined count threshold, and when the count detection signal is greater than the predetermined count In the case of a threshold value, the counting signal is output; the counting signal is counted to obtain the counting data; and the counting imaging data is generated according to the counting data.

In some embodiments, comparing the counting detection signal with a predetermined counting threshold, and outputting the counting signal when the counting detection signal is greater than the predetermined counting threshold includes: comparing the counting detection signal with a plurality of predetermined counting thresholds, respectively outputting Counting the counting signal of the threshold; counting the counting signal, and obtaining the counting data includes: separately counting the counting signal corresponding to each predetermined counting threshold, and obtaining the counting data corresponding to each predetermined counting threshold; generating counting imaging data according to the counting data includes: according to the counting data Count imaging data corresponding to each predetermined count threshold is generated separately.

In some embodiments, the radiation imaging method further includes: according to the counting imaging data corresponding to each predetermined counting threshold, identifying the substance type of the measured object through which the ray passes, and outputting the substance type information.

In some embodiments, the radiation imaging method further includes: generating integral imaging data according to the second detection signal; and acquiring a second fusion image according to the count imaging data and the integral imaging data.

In some embodiments, the radiation imaging method further includes: acquiring a third fused image according to the integral imaging data, the first imaging data and the count imaging data.

In some embodiments, the radiation imaging method further includes: acquiring a fourth fused image according to the integral imaging data and the first imaging data.

In some embodiments, generating the integrated imaging data according to the second detection signal includes: performing an integration operation according to the second detection signal to output the integrated data; generating the integrated digital signal according to the integrated data; and generating the integrated imaging data according to the integrated digital signal.

In some embodiments, the radiation imaging method further includes: after the counting detector generates the second detection signal, amplifying the second detection signal according to a predetermined integral amplification factor through a first-stage amplifier to generate an integral detection signal; generating an integral detection signal according to the second detection signal The counting imaging data includes: amplifying the integrated detection signal according to a predetermined counting amplification factor, and obtaining the counting detection signal, so as to generate the counting imaging data according to the counting detection signal; and generating the integral imaging data according to the second detection signal includes: generating the integral imaging data according to the integrated detection signal .

Description of drawings

The drawings described here are used to provide a further understanding of the present disclosure, and constitute a part of the present disclosure. The schematic embodiments of the present disclosure and their descriptions are used to explain the present disclosure, and do not constitute improper limitations to the present disclosure. In the attached picture:

FIG. 1 is a schematic diagram of some embodiments of a radiation imaging system of the present disclosure.

FIG. 2 is a schematic diagram of some embodiments of a counting imaging device in a radiation imaging system of the present disclosure.

3 is a schematic diagram of some embodiments of an integral imaging device in a radiation imaging system of the present disclosure.

FIG. 4 is a schematic diagram of other embodiments of the radiation imaging system of the present disclosure.

5 is a flowchart of some embodiments of radiation imaging methods of the present disclosure.

FIG. 6 is a flowchart of other embodiments of the radiation imaging method of the present disclosure.

Fig. 7 is a flowchart of some embodiments of counting detector-based detection signal imaging in the radiation imaging method of the present disclosure.

detailed description

The technical solution of the present disclosure will be described in further detail below with reference to the drawings and embodiments.

Since a highly sensitive detector often has a low saturation threshold, when it is directly exposed to rays with a flux higher than the saturation threshold of the detector, the imaging effect will be reduced.

A schematic diagram of some embodiments of a radiation imaging system of the present disclosure is shown in FIG. 1 .

A PD (Photo-Diode, photodiode) detector 110 is located on a radiation receiving surface of the radiation imaging system, and can generate a first detection signal according to the received radiation. The first imaging device 111 is connected to the PD detector, and can generate first imaging data according to the first detection signal. In some embodiments, the first imaging device 111 can send the generated first imaging data to a display for display, or store it in a predetermined storage path for subsequent recall.

The counting detector 120 is located on the side of the PD detector away from the ray receiving surface, receives the ray passing through the photodiode detector during use, and generates a second detection signal. A counting detector refers to a detector whose detection data supports the function of counting imaging. In some embodiments, the detection data of the counting detector can also be imaged by means other than counting imaging, such as integral imaging. In some embodiments, the counting detector can be a SiPM detector or a CZT detector. In some embodiments, the scintillator coupled to the SiPM detector can be a lead tungstate PbWO4 scintillator, which is beneficial to improve detection density and detection efficiency. The counting imaging device 121 is connected to the counting detector 120 and can generate counting imaging data according to the second detection signal. In some embodiments, the counted imaging data refers to the counting processing of the second detection signal with a predetermined counting threshold, and the counting signal is used for imaging data. In some embodiments, the counting imaging device 121 can send the generated counting imaging data to a display for display, or store it in a predetermined storage path for subsequent recall.

The image fusion device 130 is connected to the first imaging device 111 and the counting imaging device 121, and can fuse the first imaging data and the counting imaging data to obtain a first fusion image. In some embodiments, an image fusion technology may be used to fuse the first imaging data and counting imaging data based on a set first weight ratio to generate a first fusion image. In some embodiments, the image fusion device 130 can send the generated first fusion image to a display for display, or store it in a predetermined storage path for subsequent recall.

Such a radiation imaging system can simultaneously generate detection data based on PD detectors and detection data based on counting detectors, and integrate the two to improve detection quality; at the same time, under the same initial flux, after PD detection The shading of the detector reduces the flux of X-rays reaching the counting detector, thereby reducing the probability of counting detector saturation and further improving the detection quality, especially in extremely high-flux X-ray detection, the effect is more obvious.

In some embodiments, as shown in FIG. 2 , the radiation imaging system further includes an integral imaging device 122 capable of generating integral imaging data according to the second detection signal generated by the counting detector 120 . In some embodiments, the integrated imaging data refers to the data obtained by performing integral processing on the second detection signal and using the integrated signal to perform imaging. In some embodiments, the integral imaging device 122 can send the generated integral imaging data to a display for display, or store it in a predetermined storage path for subsequent recall.

The image fusion device 130 can also be connected to the integral imaging device 122 . In some embodiments, the image fusion device 130 can fuse count imaging data and integral imaging data to obtain a second fusion image. In some embodiments, an image fusion technology may be used to fuse integral imaging data and count imaging data based on a set second weight ratio to generate a second fusion image.

Such a radiation imaging system can synchronously generate counting imaging data and integral imaging data according to the detection results of the counting detector, and fuse the two, while taking advantage of the advantages of counting imaging and integral imaging to improve imaging quality. In some embodiments, according to the characteristics of counting and integral imaging adaptability under different flux conditions, the second weight ratio can be dynamically adjusted. For example, as the flux increases, the weight of integral imaging data decreases. Weights.

In some embodiments, considering that the integral imaging mode is based on the sum of the photon responses of the counting detectors, while the counting imaging mode is based on the number of photons in response to the counting detectors, the two are not in the same dimension, therefore, it can be estimated The average response coefficient when the number of photons is converted into photon energy response. In some embodiments, performing imaging and imaging data analysis on the detection data of a uniform material with a predetermined thickness, comparing the integral response brightness value with the counting rate of the counting mode to obtain an average response coefficient, and multiplying the counting imaging image by this coefficient, The imaging data of the two modes are transformed into the same dimension, and then the images of the two modes are fused according to the second weight ratio to obtain a second fused image.

Such a radiation imaging system can first convert the integrated and counted imaging data into the same dimension and then further fuse them to improve the rationality of image fusion and further improve the accuracy of imaging.

In some embodiments, the image fusion device 130 can also fuse the integral imaging data, the first imaging data and the count imaging data to obtain a third fusion image, so as to take advantage of the advantages of the three and improve the imaging quality. In some embodiments, image fusion technology may be used to fuse the first imaging data, integral imaging data and counting imaging data based on a set third weight ratio to generate a third fused image.

In some embodiments, the image fusion device 130 can also fuse the integral imaging data with the first imaging data to obtain a fourth fusion image. In some embodiments, an image fusion technology may be used to fuse the first imaging data and integral imaging data based on a set fourth weight ratio to generate a fourth fusion image. Such a radiation imaging system can further improve the flexibility of image fusion, is conducive to providing more fusion solutions, and improves the possibility of obtaining higher-quality imaging data.

In some embodiments, the above weight ratios can be dynamically adjusted according to the signal-to-noise ratio, so as to optimize the imaging effect. In some embodiments, each weight ratio can be dynamically adjusted for different X-ray fluxes.

In some embodiments, the counting imaging device is as shown in FIG. 2 .

The counting amplifier 201 is capable of receiving the second detection signal from the counting detector. In some embodiments, the counting amplifier 201 can directly receive the second detection signal, and then amplify it with a preset amplification factor; in other embodiments, the second detection signal can be input into the counting amplifier 201 after a stage of amplification . The counting amplifier 201 amplifies the received signal according to a predetermined counting amplification factor, and outputs a counting detection signal. In some embodiments, the predetermined count amplification factor can be set and adjusted according to the obtained penetration index value.

The comparator 202 is connected to the counting amplifier 201, and can compare the counting detection signal with a predetermined counting threshold, and output the counting signal to the counter when the counting detection signal is greater than the predetermined counting threshold.

The counter 203 can count the counting signal output by the comparator to obtain counting data.

The count imaging device 204 is capable of generating count imaging data from the count data.

Such a radiation imaging system can first amplify the detection data based on the data accuracy required in the counting imaging process to avoid excessive errors caused by weak signal strength and improve signal quality.

In some embodiments, the counting imaging device can generate multiple counting imaging data by setting different predetermined counting thresholds for the same second detection signal. In some embodiments, the number of preset counting thresholds may be 2, so as to realize dual-energy counting imaging.

In some embodiments, the comparator 202 compares the counting detection signal with a plurality of different predetermined counting thresholds, and outputs a counting signal corresponding to each predetermined counting threshold respectively. In some embodiments, a plurality of comparators 202 may be provided, and each comparator performs a comparison with a predetermined count threshold and outputs a comparison result. In some embodiments, the comparator 202 may be a single-input multiple-output comparator, which outputs a comparison result with multiple different predetermined counting thresholds according to the input signal.

The counter 203 can separately count counting signals corresponding to each predetermined counting threshold based on the data output by the comparator 202, and obtain counting data corresponding to each predetermined counting threshold. In some embodiments, there may be multiple counters 203, and each counter performs counting processing of one count signal to generate count data. In some embodiments, the counter 203 can be single, with the function of multi-input and multi-output, and the entrances correspond to the exits one by one. Each entrance receives one counting signal, and the counter counts each counting signal separately.

The counting imaging device 204 can respectively generate counting imaging data corresponding to each predetermined counting threshold according to the counting data. In some embodiments, there may be multiple counting imaging devices, and each counting imaging device can generate counting imaging data according to one channel of counting data. In some other embodiments, the counting and imaging device 204 has the function of multiple inputs and multiple outputs, and the entrances correspond to the exits one by one. Each entrance receives one channel of counting data, and the counting and imaging device 204 images each channel of counting data separately.

Such a radiation imaging system can simultaneously generate multiple sets of counting imaging data for the same second detection signal, and obtain radiation imaging for different energy segments by setting different counting thresholds, which improves the utilization rate of radiation detection signals and is beneficial to Selecting from multiple images increases the likelihood of obtaining higher quality imaging data.

In some embodiments, as shown in FIG. 2 , the radiation imaging system further includes a substance identification device 205 . The substance identifying device 205 can identify the substance type of the measured object through which the rays pass through according to the counting imaging data corresponding to each predetermined counting threshold, and output the substance type information. Since the same substance has different effects on rays of different fluxes, and different substances have different effects on rays of the same flux, for example, in low-energy regions, the photoelectric effect is dominant, and has a strong atomic number with the material of the object to be inspected. Correlation; Compton scattering is dominant in the middle and low energy regions, and is weakly correlated with the atomic number; the ratio of the attenuation coefficients under the two energies changes monotonously with the atomic number. Therefore, by detecting different energy segments in the detection of the same object The signal is imaged, enabling substance identification. In some embodiments, the corresponding relationship may be pre-stored, such as establishing a database or a relational table. Based on the pre-stored data, the substance identification device 205 analyzes the counting imaging data obtained for the same second detection data and corresponding to different predetermined counting thresholds to determine the substance of the measured object, for example, determine the atomic number.

Such a radiation imaging system can determine the material type of the measured object through one detection, further improves the utilization rate of the detection signal, and improves the detection accuracy.

In some embodiments, the integral imaging device may be as shown in FIG. 3 .

The integrator 301 is connected with the preceding device, such as directly connected with the counting detector to obtain the second detection signal; or connected with the amplifier directly connected with the counting detector to obtain the amplified signal. The integrator 301 performs an integration operation on the received signal, and outputs integration data.

The ADC (Analog to Digital Converter, analog-to-digital converter) 302 performs analog-to-digital conversion on the integral data to generate an integral digital signal.

The integral imaging device 303 generates integral imaging data according to the integral digital signal.

Such an integral imaging device can perform integral imaging based on the detection result of the counting detector, thereby improving the utilization rate of the second detection signal.

A schematic diagram of another embodiment of the radiation imaging system of the present disclosure is shown in FIG. 4 .

PD detector 410, first imaging device 411, counting detector 420, image fusion device 430, integral imaging device including integrator 4231, ADC 4232 and integral imaging device 4233, and counting amplifier 4221, comparator 4222, counter 4223 The counting imaging equipment of the counting imaging device 4224 can be similar to the above embodiments. The radiation imaging system also includes a first-stage amplifier 421 .

The primary amplifier 421 is located between the counting detector and the counting imaging device, and between the counting detector and the integral imaging device. After receiving the second detection signal from the counting detector 420, the primary amplifier 421 amplifies the second detection signal according to a predetermined integral amplification factor, generates an integral detection signal, and outputs it to the counting imaging device and the integral imaging device respectively. The integral imaging device uses the received integral detection signal to perform imaging, while the counting imaging device uses the counting amplifier 4221 to perform secondary amplification on the integral detection signal before performing counting imaging processing.

Such a radiation imaging system can take into account the different characteristics of signal intensity requirements in integration and counting processing, and adopts a two-stage amplification method for different imaging methods to ensure the quality of counting and integral imaging; in addition, the two-stage amplification method is also It avoids the problem of introducing too much noise when a single amplifier is used for high amplitude amplification, and further ensures the image quality.

A flowchart of some embodiments of the radiation imaging method of the present disclosure is shown in FIG. 5 . In some embodiments, the radiation imaging method of the present disclosure may be based on any radiation imaging system mentioned above.

In step 501, a photodiode detector receives radiation from a radiation source, generates a first detection signal, and generates first imaging data according to the first detection signal.

In step 502, the counting detector receives the rays passing through the photodiode detector, generates a second detection signal, and generates counting imaging data according to the second detection signal.

In some embodiments, the first detection signal is generated prior to the second detection signal due to differences in detector deployment locations. The first imaging data and the counting imaging data can be generated synchronously or asynchronously.

In step 503, a first fused image is obtained according to the first imaging data and the counted imaging data. In some embodiments, an image fusion technology may be used to fuse the first imaging data and counting imaging data based on a set first weight ratio to generate a first fusion image.

Through this method, the detection data based on the PD detector and the detection data based on the counting detector can be generated synchronously, and the two are fused to improve the detection quality; at the same time, under the same initial flux, the PD detector The shading reduces the probability of counting detector saturation, further improves the detection quality, and can also expand the application range, especially in extremely high-throughput X-ray detection, the effect of improving the detection quality is more obvious.

A flowchart of other embodiments of the radiation imaging method of the present disclosure is shown in FIG. 6 .

In step 601, a PD detector receives radiation from a radiation source, generates a first detection signal, and generates first imaging data according to the first detection signal.

In step 602, the counting detector receives rays passing through the PD detector, generates a second detection signal, and generates counting imaging data and integral imaging data according to the second detecting signal.

In some embodiments, the first detection signal is generated prior to the second detection signal due to differences in detector deployment locations. The first imaging data, the count imaging data and the integral imaging data may be generated synchronously or asynchronously.

In some embodiments, one or more of steps 603-606 may be optionally performed.

In step 603, a first fused image is acquired according to the first imaging data and the counted imaging data. In some embodiments, an image fusion technology may be used to fuse the first imaging data and counting imaging data based on a set first weight ratio to generate a first fusion image.

In step 604, the count imaging data and integral imaging data are fused to obtain a second fused image. In some embodiments, an image fusion technology may be used to fuse integral imaging data and count imaging data based on a set second weight ratio to generate a second fusion image.

In some embodiments, the counting imaging data can be converted into the same dimension as the integral imaging data before fusion, so as to improve the rationality of fusion.

In step 605, the integral imaging data, the first imaging data and the counting imaging data are fused to obtain a third fused image, so as to improve the imaging quality by utilizing the advantages of the three. In some embodiments, image fusion technology may be used to fuse the first imaging data, integral imaging data and counting imaging data based on a set third weight ratio to generate a third fused image.

In step 606, the integral imaging data and the first imaging data are fused to obtain a fourth fused image. In some embodiments, an image fusion technology may be used to fuse the first imaging data and integral imaging data based on a set fourth weight ratio to generate a fourth fusion image.

Through this method, a variety of imaging data can be obtained in one detection, and a variety of fusion images can be obtained through different fusion methods, which improves the utilization rate of detection data, improves the flexibility of image fusion, and more fusion Protocols help increase the likelihood of obtaining higher-quality imaging data.

In the radiation imaging method of the present disclosure, the flow chart of some embodiments of the process of generating count imaging data and integral imaging data according to the second detection signal is shown in FIG. 7 .

In step 701, after the counting detector generates the second detection signal, the second detection signal is amplified according to a predetermined integral amplification factor through a first-stage amplifier to generate an integral detection signal, and then step 712 and step 722 are executed.

In step 712, the counting amplifier amplifies the received integral detection signal according to a predetermined counting amplification factor, and outputs the counting detection signal.

In step 713, the counting detection signal is compared with a predetermined counting threshold, and if the counting detection signal is greater than the predetermined counting threshold, the counting signal is output to the computer. In some embodiments, the number of predetermined count thresholds may be 1, or greater than 1, such as two different predetermined count thresholds.

In step 714, the counting signal is counted to obtain counting data.

In step 715, count imaging data is generated from the count data.

In some embodiments, when the number of predetermined counting thresholds is greater than 1, counting imaging data equal to the number of predetermined counting thresholds may be generated, and then substance identification is performed to improve detection accuracy.

In step 722, an integration operation is performed on the integrated detection signal to output integrated data.

In step 723, an analog-to-digital conversion is performed on the integrated data to generate an integrated digital signal.

In step 724, integrated imaging data is generated from the integrated digital signal.

Through such a method, the second detection signal can be provided to different imaging methods in a two-stage amplification method, which ensures the quality of counting and integral imaging; in addition, the two-stage amplification method also avoids the high-intensity amplification of a single amplifier. The problem of excessive noise is introduced to further ensure the imaging quality.

The present disclosure is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the present disclosure. It should be understood that each procedure and/or block in the flowchart and/or block diagram and a combination of procedures and/or blocks in the flowchart and/or block diagram can be realized by computer program instructions. These computer program instructions may be provided to a general purpose computer, special purpose computer, embedded processor, or processor of other programmable data processing equipment to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing equipment produce a An apparatus for realizing the functions specified in one or more procedures of the flowchart and/or one or more blocks of the block diagram.

These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to operate in a specific manner, such that the instructions stored in the computer-readable memory produce an article of manufacture comprising instruction means, the instructions The device realizes the function specified in one or more procedures of the flowchart and/or one or more blocks of the block diagram.

These computer program instructions can also be loaded onto a computer or other programmable data processing device, causing a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process, thereby The instructions provide steps for implementing the functions specified in the flow chart or blocks of the flowchart and/or the block or blocks of the block diagrams.

So far, the present disclosure has been described in detail. Certain details known in the art have not been described in order to avoid obscuring the concept of the present disclosure. Based on the above description, those skilled in the art can fully understand how to implement the technical solutions disclosed herein.

The methods and apparatus of the present disclosure may be implemented in many ways. For example, the methods and devices of the present disclosure may be implemented by software, hardware, firmware or any combination of software, hardware, and firmware. The above sequence of steps for the method is for illustration only, and the steps of the method of the present disclosure are not limited to the sequence specifically described above unless specifically stated otherwise. Furthermore, in some embodiments, the present disclosure can also be implemented as programs recorded in recording media including machine-readable instructions for realizing the method according to the present disclosure. Thus, the present disclosure also covers a recording medium storing a program for executing the method according to the present disclosure.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present disclosure and not to limit them; although the present disclosure has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that: the present disclosure can still be Modifications are made to the disclosed specific implementation methods or equivalent replacements are made to some technical features; without departing from the spirit of the technical solutions of the present disclosure, all of them shall be covered by the scope of the technical solutions claimed in the present disclosure.

Claims

A radiation imaging system comprising:

a photodiode detector configured to receive radiation from the radiation source and generate a first detection signal;

a first imaging device, connected to the photodiode detector, configured to generate first imaging data according to the first detection signal;

a counting detector, located on a side of the photodiode detector away from the ray receiving surface, configured to receive the ray passing through the photodiode detector, and generate a second detection signal;

a counting imaging device, connected to the counting detector, configured to generate counting imaging data according to the second detection signal; and

The image fusion device is configured to acquire a first fusion image according to the first imaging data and the count imaging data.
The radiation imaging system of claim 1, wherein the counting imaging device comprises:

a counting amplifier configured to output a counting detection signal according to the second detection signal and a predetermined counting amplification factor;

a comparator, connected to the counting amplifier, configured to compare the counting detection signal with a predetermined counting threshold, and output a counting signal to a counter when the counting detection signal is greater than the predetermined counting threshold;

The counter is configured to count the count signal output by the comparator to obtain count data; and

A counting imaging device configured to generate the counting imaging data according to the counting data.
The radiation imaging system of claim 2, wherein:

The comparator is configured to compare the count detection signal with a plurality of predetermined count thresholds, and output a count signal corresponding to each of the predetermined count thresholds;

The counter is configured to separately count the counting signals corresponding to each of the predetermined counting thresholds, and obtain counting data corresponding to each of the predetermined counting thresholds; and

The counting imaging device is configured to respectively generate the counting imaging data corresponding to each of the predetermined counting thresholds according to the counting data.
The radiation imaging system of claim 3, further comprising:

The substance identification device is configured to, according to the count imaging data corresponding to each of the predetermined count thresholds, identify the substance type of the measured object through which the rays pass, and output substance type information.
The radiation imaging system according to claim 1, further comprising an integral imaging device configured to generate integral imaging data according to the second detection signal;

The image fusion device is further configured to acquire a second fusion image according to the count imaging data and the integral imaging data.
The radiation imaging system according to claim 5, wherein the image fusion device is further configured to acquire a third fusion image according to the integral imaging data, the first imaging data and the count imaging data.
The radiation imaging system according to claim 5 or 6, wherein the image fusion device is further configured to acquire a fourth fusion image according to the integral imaging data and the first imaging data.
The radiation imaging system of claim 5, wherein the integral imaging device comprises:

an integrator configured to perform an integration operation according to the second detection signal, and output integration data;

an analog-to-digital converter configured to generate an integrated digital signal based on the integrated data; and

An integral imaging device configured to generate the integral imaging data according to the integral digital signal.
The radiation imaging system according to claim 5, further comprising: a primary amplifier, located between the counting detector and the counting imaging device, and between the counting detector and the integral imaging device, configured to The second detection signal is amplified by a predetermined integral amplification factor to generate an integral detection signal, which is output to the counting imaging device and the integral imaging device.
The system of claim 1, wherein the counting detector comprises a silicon photomultiplier (SiPM) detector or a cadmium zinc telluride (CZT) detector.
A method of radiographic imaging comprising:

receiving radiation from the radiation source through a photodiode detector, generating a first detection signal, and generating first imaging data according to the first detection signal;

receiving rays passing through the photodiode detector by a counting detector, generating a second detection signal, and generating counting imaging data according to the second detection signal; and

Acquiring a first fused image according to the first imaging data and the counting imaging data.
The radiation imaging method according to claim 11, wherein said generating count imaging data according to said second detection signal comprises:

Acquiring a count detection signal according to the second detection signal and a predetermined count amplification factor;

comparing the count detection signal with a predetermined count threshold, and outputting a count signal if the count detection signal is greater than the predetermined count threshold;

counting the counting signals to obtain counting data; and

The count imaging data is generated from the count data.
The radiation imaging method according to claim 12, wherein,

The comparing the counting detection signal with a predetermined counting threshold, and outputting the counting signal when the counting detection signal is greater than the predetermined counting threshold comprises: comparing the counting detection signal with a plurality of the predetermined counting thresholds, respectively outputting counting signals corresponding to each of the predetermined counting thresholds;

The counting the counting signal and obtaining the counting data includes: separately counting the counting signal corresponding to each of the predetermined counting thresholds, and obtaining the counting data corresponding to each of the predetermined counting thresholds; and

The generating the counting imaging data according to the counting data includes: respectively generating the counting imaging data corresponding to each of the predetermined counting thresholds according to the counting data.
The radiation imaging method of claim 13, further comprising:

According to the counting imaging data corresponding to each of the predetermined counting thresholds, the substance type of the measured object through which the rays pass is identified, and the substance type information is output.
The radiation imaging method of claim 11, further comprising:

generating integrated imaging data based on the second detection signal; and

Acquiring a second fusion image according to the count imaging data and the integral imaging data.
The radiation imaging method according to claim 15, further comprising: acquiring a third fused image according to the integral imaging data, the first imaging data and the count imaging data.
The radiation imaging method according to claim 15 or 16, further comprising: acquiring a fourth fused image according to the integral imaging data and the first imaging data.
The radiation imaging method according to claim 15, wherein said generating integral imaging data according to said second detection signal comprises:

performing an integration operation according to the second detection signal, and outputting integration data;

generating an integrated digital signal based on said integrated data; and

The integrated imaging data is generated from the integrated digital signal.
The radiation imaging method of claim 15, further comprising:

After the counting detector generates the second detection signal, the second detection signal is amplified according to a predetermined integral amplification factor through a first-stage amplifier to generate an integral detection signal;

The generating counting imaging data according to the second detection signal includes: amplifying the integrated detection signal according to a predetermined counting amplification factor, and obtaining the counting detection signal, so as to generate counting imaging data according to the counting detection signal;

The generating integral imaging data according to the second detection signal includes: generating integral imaging data according to the integrated detection signal.