Multi-purpose imaging system and imaging method

Abstract

This invention provides a multi-energy imaging system and imaging method. The multi-energy imaging system includes a multi-energy X-ray source and a single detector. The multi-energy X-ray source generates X-rays for projection imaging and rotates circumferentially along the detector. It includes a first X-ray source and a second X-ray source that rotate synchronously. The first and second X-ray sources are arranged along the rotation plane of the multi-energy X-ray source and alternately emit X-rays of first energy and second energy. The second X-ray source is located at T... 2n‑1 The position at time T0 coincides with the position of the first X-ray source at time T0, where n is a natural number; a single detector alternately receives X-rays of a first energy emitted by the first X-ray source and X-rays of a second energy emitted by the second X-ray source and images them respectively. Compared with the prior art, the multi-energy imaging system of the present invention has a lower cost and can achieve data acquisition of different energies at the same angle.

Description

Technical Field

[0001] This invention relates to a multi-energy imaging system and imaging method, belonging to the field of medical device technology. Background Technology

[0002] Dual-energy CT imaging technology is increasingly being used in medical CT equipment. Compared with traditional single-energy CT imaging technology, dual-energy virtual single-energy imaging technology has significant advantages in scenarios such as removing metal artifacts, quantitative analysis of substances, and reducing the amount of contrast agent used.

[0003] In the field of dual-energy or multi-energy CT, the mainstream CT imaging technologies currently include rapid kilovolt switching, dual-source dual-detection, and dual-layer detector technologies. However, each of these technologies has its advantages and disadvantages. For example, rapid kilovolt switching can achieve dual-energy scanning, but it cannot simultaneously acquire data from two different energies at the same angle, and the distinction between the two energy spectra is relatively poor, resulting in mediocre virtual single-energy imaging. Dual-energy dual-detection technology can improve the distinction between the two energy spectra, but the acquisition time interval between the two energies is relatively long, which can easily introduce motion artifacts caused by excessively long time intervals into virtual single-energy images, and the cost of two sets of X-ray source systems is high. The advantage of dual-detector technology is that it can obtain data from two different energies at the same angle, but the distinction between the two energy spectra is relatively poor.

[0004] In view of this, it is indeed necessary to provide a multi-energy imaging system and imaging method to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide a low-cost, multi-energy imaging system and method that can acquire high-energy and low-energy X-ray images at the same angle.

[0006] To achieve the above objectives, the present invention provides a multi-energy imaging system, comprising a multi-energy X-ray source and a single detector. The multi-energy X-ray source generates X-rays for projection imaging and rotates circumferentially along the detector. The system includes a first X-ray source and a second X-ray source, which are arranged along the rotation plane of the multi-energy X-ray source and alternately emit X-rays of first energy and second energy. The second X-ray source is located at T... 2n-1 The position of the detector at time T0 coincides with the position of the first radiation source at time T0, where n is a natural number; the single detector alternately receives radiation of the first energy emitted by the first radiation source and radiation of the second energy emitted by the second radiation source and images them respectively.

[0007] As a further improvement of the present invention, the positional relationship between the first radiation source and the second radiation source satisfies the equation 2*D*sin(s*(2n-1)*t / 2)=d, where d is the focal distance between the first radiation source and the second radiation source, D is the rotation radius of the multi-energy radiation source, s is the rotation angular velocity of the multi-energy radiation source, n is a natural number, and t is the exposure time interval.

[0008] As a further improvement of the present invention, the first energy is greater than the second energy, and a filter device is provided between the first radiation source and the detector. The filter device is located close to the first radiation source and remains relatively stationary with respect to the first radiation source.

[0009] As a further improvement of the present invention, the multi-energy imaging system further includes an image acquisition and processing unit, which performs virtual mono-energy imaging on the rays emitted by the first ray source and the second ray source at the same position received by the detector.

[0010] As a further improvement of the present invention, the image acquisition and processing unit performs virtual monoenergetic imaging on the second radiation source before performing virtual monoenergetic imaging on the second radiation source. 2n-1 The projection data at time T0 is rearranged to correspond with the projection data of the first ray source at time T0, and the effective data range of the virtual monoenergetic imaging is the sum of the projection data of the first ray source at time T0 and the projection data of the second ray source at time T0. 2n-1 The overlapping portion of the projected data at any given time.

[0011] The present invention also provides an imaging method applied to the aforementioned multi-energy imaging system, comprising the following steps:

[0012] S1: The first and second radiation sources are arranged along the rotation plane of the multi-energy radiation source and alternately emit radiation of first and second energy. The second radiation source is located at T... 2n-1 The position at time T0 coincides with the position of the first ray source at time T0, where n is a natural number;

[0013] S2: A single detector alternately receives rays of first energy emitted by the first radiation source and rays of second energy emitted by the second radiation source and images them respectively;

[0014] S3: The image acquisition and processing unit performs virtual monoenergetic imaging on the rays emitted by the first ray source and the second ray source at the same position received by the detector.

[0015] As a further improvement of the present invention, the positional relationship between the first radiation source and the second radiation source satisfies the equation 2*D*sin(s*(2n-1)*t / 2)=d, where d is the focal distance between the first radiation source and the second radiation source, D is the rotation radius of the multi-energy radiation source, s is the rotation angular velocity of the multi-energy radiation source, n is a natural number, and t is the exposure time interval.

[0016] As a further improvement of the present invention, before performing virtual monoenergetic imaging on the rays emitted by the first ray source and the second ray source at the same position, the image acquisition and processing unit first rearranges the projection data of the first ray source / second ray source so that it corresponds to the projection data of the second ray source / first ray source.

[0017] As a further improvement of the present invention, the projection data of the first ray source at time T0 is P0(u0,v0,0), and the projection data of the second ray source at time T0 is P0(u0,v0,0). 2n-1 The projection data at time T is P1(u1,v1,T0+2n-1), and the data acquisition and processing unit projects the second ray source onto T. 2n-1 The method for rearranging the time-projected data P1 to the corresponding time-T0 P1' is as follows:

[0018] P′1(u0,v0,T0)=P1(u1,v1,T0+2n-1)

[0019]

[0020]

[0021] Where d is the focal distance between the first and second radiation sources, L is the distance from the center point of the line connecting the first and second radiation sources to the detector, and θ is the distance from the detector at time T0 to T... 2n-1 The angle of rotation at any given moment.

[0022] As a further improvement of the present invention, the effective data range of the virtual monoenergetic imaging is the projection data of the first ray source at time T0 and the projection data of the second ray source at time T0. 2n-1 The overlapping portion of the projected data at any given time.

[0023] The beneficial effects of this invention are: compared with the prior art, the multi-energy imaging system and imaging method of this invention reduce the cost of the imaging system by using a single detector to receive rays of different energies emitted by a multi-energy ray source. Furthermore, by arranging the first ray source and the second ray source along the rotation plane of the multi-energy ray source and alternately emitting rays of the first and second energies, the second ray source at T... 2n-1The position at time T0 coincides with the position of the first radiation source at time T0, where n is a natural number, so as to achieve data acquisition of the first and second energies from radiation sources at the same angle. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of a multi-energy imaging system in the prior art.

[0025] Figure 2 This is a schematic diagram of the structure of a multi-energy imaging system according to a preferred embodiment of the present invention.

[0026] Figure 3 This is a schematic diagram of the multi-energy imaging system of the present invention.

[0027] Figure 4 This is a schematic diagram of the motion angle of the detector of the present invention.

[0028] Figure 5 This is the spectral diagram of the multi-energy imaging system of the present invention without a filtering device.

[0029] Figure 6 This is a spectral diagram of the multi-energy imaging system with a filtering device according to the present invention.

[0030] Figure 7 This is a schematic diagram of the irradiation range of the first radiation source at time T0.

[0031] Figure 8 The second radiation source is in T 2n-1 A schematic diagram of the illumination range at any given time.

[0032] Figure 9 This is a schematic diagram of the effective illumination range of the multi-energy imaging system of the present invention.

[0033] Figure 10 This is a flowchart of the imaging method of the present invention. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] It should be noted that, in order to avoid obscuring the present invention with unnecessary details, only the structures and / or processing steps closely related to the present invention are shown in the accompanying drawings, while other details that are not closely related to the present invention are omitted.

[0036] Additionally, it should be noted that the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0037] Please see Figure 1 As shown, these are the three main technical routes for existing multi-energy imaging systems, among which... Figure 1 (a) shows the rapid kilovolt switching method of GE, in which the X-ray source alternately acquires X-ray images of different energies by switching between high and low voltages (usually 80kV and 140kV) during CT scanning. However, GE uses the high and low voltage switching method to complete dual-energy scanning, which cannot achieve simultaneous acquisition of data from two different energies at the same angle, and the distinction between the two energy spectra is relatively poor, resulting in a generally poor virtual single-energy imaging effect. Figure 1 (b) The Siemens approach uses two imaging systems, set to 80 kV and 140 kV respectively, with an additional X-ray filter introduced in front of the 140 kV source to further distinguish the two X-ray spectra of different energies. However, Siemens' dual-energy dual-detection approach requires two sets of X-ray source systems, which is costly, and the long acquisition time interval between the two energies can easily introduce motion artifacts caused by excessively long time intervals into the virtual single-energy image. Figure 1 (c) is Philips' dual-energy detector method, which can obtain high-energy and low-energy X-ray images at the same angle, which is beneficial for subsequent image processing operations, but the distinction between the two energy spectra is relatively poor.

[0038] To address the problems in the prior art, this invention provides a multi-energy imaging system 100 and an imaging method. Please refer to... Figure 2-3 As shown, the multi-energy imaging system 100 includes a multi-energy X-ray source 10 and a single detector 20. The multi-energy X-ray source 10 generates X-rays for projection imaging and rotates circumferentially along the detector 20. The single detector 20 alternately receives the X-rays emitted by the multi-energy X-ray source 10 and images them separately. By configuring the multi-energy X-ray source 10 and the single detector 20, the single detector 20 can alternately receive the X-rays emitted by the multi-energy X-ray source 10 and image them separately, thereby reducing the cost of the multi-energy imaging system 100.

[0039] It should be understood that the multi-energy X-ray source 10 of the present invention includes two X-rays of different energies for imaging, but may also include three or more X-rays of different energy spectra or energies; the present invention is not limited thereto. For clarity, the multi-energy X-ray source 10 in the following specification is described using the example of emitting two X-rays of different energies, but this should not be construed as limiting.

[0040] Please continue reading. Figure 2-3 As shown, the multi-energy radiation source 10 includes a first radiation source 11 and a second radiation source 12. The first radiation source 11 and the second radiation source 12 are arranged along the rotation plane of the multi-energy radiation source 10 and alternately emit radiation with a first energy of 111 and a second energy of 121. The second radiation source 12 is located at T... 2n-1 The position at time T0 coincides with the position of the first X-ray source 11, where n is a natural number. A single detector 20 alternately receives and images X-rays of first energy 111 emitted by the first X-ray source 11 and second energy 121 emitted by the second X-ray source 12. With this configuration, X-rays of first energy 111 and second energy 121 can be obtained at the same angle.

[0041] The first radiation source 11 and the second radiation source 12 can be X-ray tubes or any device for acquiring X-rays, such as an X-ray machine. This embodiment uses an X-ray tube as an example. The first radiation source 11 is a first X-ray tube, and the second radiation source 12 is a second X-ray tube. The first and second X-ray tubes can be the same type of X-ray tube, each with a corresponding operating voltage. Under this operating voltage, electrons move and collide with the target material, thereby emitting X-rays of corresponding energy. The operating voltage of the first and second X-ray tubes and their difference can be selected according to the energy or energy spectrum difference of the multi-energy X-rays to be obtained. Specifically, for example, in this embodiment, the first X-ray emitted by the first X-ray tube with a first energy of 111 can be X-rays with an energy of 120-160 kVp, and the second X-ray emitted by the second X-ray tube with a second energy of 121 can be X-rays with an energy of 60-100 kVp. That is, in this embodiment, the first energy 111 is greater than the second energy 121. In other words, the first radiation source 11 is a high-energy radiation source, and the second radiation source 12 is a low-energy radiation source.

[0042] Furthermore, the multi-energy imaging system 100 also includes a control device (not shown) for controlling the first X-ray source 11 to emit high-energy X-rays and the second X-ray source 12 to emit low-energy X-rays. In this embodiment, the control device includes a high-voltage generator. The first X-ray source 11 and the second X-ray source 12 are configured corresponding to the high-voltage generator. The first operating voltage V1 and the second operating voltage V2 output by the high-voltage generator are alternately applied to the first X-ray source 11 and the second X-ray source 12, respectively. Thus, the first X-ray source 11 and the second X-ray source 12 emit X-rays of different energies under different operating voltage biases, namely, X-rays of first energy 111 and X-rays of second energy 121. This configuration can reduce the cost and size of the multi-energy imaging device. In other embodiments, the control device may also control the first X-ray source 11 to emit X-rays of first energy 111 and the second X-ray source 12 to emit X-rays of second energy 121 in other ways. This invention is not limited to these embodiments.

[0043] The detector 20 can be a flat panel detector 20 or other types of detector 20, and the present invention is not limited thereto. The detector 20 can alternately receive X-rays of first energy 111 projected from the first X-ray source 11 and X-rays of second energy 121 projected from the second X-ray source 12, and image them respectively.

[0044] Please see Figure 3 and Figure 4 As shown, a multi-energy X-ray source 10 and a detector 20 rotate around the object 40 to be imaged. A first X-ray source 11 and a second X-ray source 12 are arranged alternately along the plane of rotation, and alternately emit X-rays of first energy 111 and second energy 121 during rotation. The detector 20 alternately receives the first energy 111 X-ray emitted by the first X-ray source 11 and the second energy 121 X-ray emitted by the second X-ray source 12 during rotation and images them respectively. Since the first X-ray source 11 and the second X-ray source 12 are arranged around the plane of rotation, at T = 0 (time T0), the first X-ray source 11 emits the first energy 111 X-ray at the first position, and at T = 2n-1 (time T... 2n-1 (Time, n is a natural number)

[0045] The second ray source 12 also reaches the first position and emits a ray with a second energy of 121, that is, at T 2n-1 At time T0, the position of the second radiation source 12 coincides with the position of the first radiation source 11. Since detector 20 also rotates synchronously, assume that detector 20 rotates from time T0 to T... 2n-1 Since the rotation angle is θ, the detector 20 receives a ray with a first energy of 111 emitted by the first ray source 11 at the first position. Figure 3As shown in the first range 21, the detector 20 receives the second energy 121 of the second radiation source 12 emitted from the first position. Figure 3 The second range 22 is shown.

[0046] To ensure that a single detector 20 can alternately receive rays of first energy 111 and second energy 121 emitted from the first radiation source 11 and the second radiation source 12 at the same location, the positional relationship between the first radiation source 11 and the second radiation source 12 must satisfy the equation 2*D*sin(s*(2n-1)*t / 2)=d. Here, d is the focal distance between the first radiation source 11 and the second radiation source 12, D is the rotation radius of the multi-energy radiation source 10 (the distance from the rotation center O to the focal point of the radiation source), s is the rotational angular velocity of the multi-energy radiation source 10, n is a natural number, and t is the exposure time interval. This allows the multi-energy imaging system 100 to obtain rays of first energy 111 and second energy 121 at the same location, facilitating subsequent image processing to combine and reconstruct the three-dimensional structure of the object 40 to be imaged.

[0047] To improve the separation capability between the first energy 111 rays and the second energy 121 rays, this invention also includes a filter device 30 between the first ray source 11 and the detector 20. The filter device 30 is positioned close to the first ray source 11 and remains relatively stationary. In other words, the filter device 30 is fixedly positioned in front of the high-energy first ray source 11 to improve the separation capability between high-energy and low-energy rays. (See also...) Figure 5-6 As shown, the distinction between the first energy 111 and the second energy 121 rays without the filter device 30 is low, while the distinction between the first energy 111 and the second energy 121 rays is high after the filter device 30 is added in front of the first ray source 11.

[0048] In this embodiment, the filtering device 30 is a filter sheet, which is fixedly disposed in front of the first radiation source 11 and located between the first radiation source 11 and the object to be imaged 40. The filter sheet rotates with the rotation of the first radiation source 11 and remains relatively stationary with respect to the first radiation source 11. In other embodiments, the filtering device 30 may also be other filtering structures, and the present invention is not limited thereto.

[0049] Furthermore, the multi-energy imaging system 100 also includes an image acquisition and processing unit, which performs virtual monoenergetic imaging on the rays emitted from the first ray source 11 and the second ray source 12 at the same position received by the detector 20. That is, the image acquisition and processing unit performs virtual monoenergetic imaging on the imaging data of the first range 21 and the imaging data of the second range 22 received by the detector 20.

[0050] Before performing virtual monoenergetic imaging on the rays emitted from the first ray source 11 and the second ray source 12 at the same position, the image acquisition and processing unit first rearranges the projection data of the first ray source 11 / second ray source 12 so that they correspond to the projection data of the second ray source 12 / first ray source 11. Then, the image acquisition and processing unit performs virtual monoenergetic imaging on the one-to-one corresponding projection data of the first energy 111 (high energy) and the second energy 121 (low energy). In this way, a better virtual monoenergetic imaging effect can be obtained.

[0051] Please see Figure 7-8 As shown, the projection data of the first X-ray source 11 at time T = 0 is P0(u0,v0,0), and the projection data of the second X-ray source 12 at time T = 2n-1 is P1(u1,v1,T0+2n-1). The image acquisition and processing unit rearranges the projection data P1(u1,v1,T0+2n-1) of the second X-ray source 12 at time T = 2n-1 to P1'(u0,v0,0) to achieve the correspondence between the projection data of the first energy 111 and the second energy 121. Let θ be the angle by which the detector 20 rotates from time T = 0 to time T = 2n-1, then θ = s(2n-1)t. Let L be the distance from the rotation center of the multi-energy imaging system 100 to the detector 20. The method for rearranging the projection data P1 of the second X-ray source 12 at time T = T0+2n-1 to the corresponding time T0 P1' is as follows:

[0052] P′1(u0,v0,T0)=P1(u1,v1,T0+2n-1)

[0053]

[0054]

[0055] Where d is the focal distance between the first radiation source 11 and the second radiation source 12, L is the distance from the center point of the line connecting the first radiation source 11 and the second radiation source 12 to the detector 20, and θ is the distance from time T0 to time T... 2n-1 The angle of rotation at any given moment.

[0056] It should be noted that in a preferred embodiment of the present invention, the projection data P1 of the second radiation source 12 at time T = T0 + 2n - 1 is rearranged to the corresponding time P1' at time T0 to perform virtual monoenergetic imaging. In other embodiments, rearranging the projection data of the first radiation source 11 to the data at the time corresponding to the second radiation source 12 to perform virtual monoenergetic imaging also falls within the protection scope of the present invention.

[0057] Please see Figure 9As shown, since the detector 20 receives the first energy 111 emitted by the first radiation source 11 at the first position, which is the first range 21, and the detector 20 receives the second energy 121 emitted by the second radiation source 12 at the first position, which is the second range 22, the effective data range for virtual monoenergetic imaging by the image acquisition and processing unit is the projection data of the first radiation source 11 at time T0 and the projection data of the second radiation source 12 at time T0. 2n-1 The overlapping portion of the projected data at time t, i.e. Figure 9 The area enclosed by the solid line in the middle.

[0058] Please see Figure 10 As shown, the present invention also provides an imaging method applied to the aforementioned multi-energy imaging system 100, comprising the following steps:

[0059] S1: The first radiation source 11 and the second radiation source 12 are arranged along the rotation plane of the multi-energy radiation source 10, and alternately emit radiation of first energy 111 and second energy 121. The second radiation source 12 is located at T... 2n-1 The position at time T0 coincides with the position of the first ray source 11 at time T0, where n is a natural number;

[0060] S2: A single detector 20 alternately receives and images rays of first energy 111 emitted by the first radiation source 11 and rays of second energy 121 emitted by the second radiation source 12.

[0061] S3: The image acquisition and processing unit performs virtual monoenergetic imaging on the rays emitted from the first ray source 11 and the second ray source 12 at the same position received by the detector 20.

[0062] This imaging method can reduce the cost of the multi-energy imaging system 100, while enabling the acquisition of high-energy and low-energy X-ray data at the same angle, facilitating subsequent virtual single-energy imaging processing.

[0063] Furthermore, in order for a single detector 20 to alternately receive the first energy 111 and the second energy 121 rays emitted by the first radiation source 11 and the second radiation source 12 at the same location, the positional relationship between the first radiation source 11 and the second radiation source 12 needs to satisfy the equation 2*D*sin(s*(2n-1)*t / 2)=d. Here, d is the focal distance between the first radiation source 11 and the second radiation source 12, D is the rotation radius of the multi-energy radiation source 10 (the distance from the rotation center O to the focal point of the radiation source), s is the rotational angular velocity of the multi-energy radiation source 10, n is a natural number, and t is the exposure time interval.

[0064] Furthermore, the image acquisition and processing unit performs virtual monoenergetic imaging on the rays emitted by the first ray source 11 and the second ray source 12 at the same position. Before virtual monoenergetic imaging, the projection data of the first ray source 11 / second ray source 12 is rearranged to correspond with the projection data of the second ray source 12 / first ray source 11. The specific rearrangement method is similar to the method described above and will not be repeated here. The effective data range of virtual monoenergetic imaging is the projection data of the first ray source 11 at time T0 (P0) and the projection data of the second ray source 12 at time T0 (P0). 2n-1 The overlapping portion of the projection data P1 at time point.

[0065] It should be understood that, when the multi-energy imaging system 100 is in use, the object 40 to be imaged is wholly or partially placed within the range of X-rays projected from the first X-ray source 11 and the second X-ray source 12 and is subjected to X-ray radiation of corresponding energy. The object 40 to be imaged can be a person or a human organ or body part, or it can be other subjects under examination, and its application may vary depending on the application field of the multi-energy imaging system 100 according to the present invention.

[0066] In summary, the multi-energy imaging system 100 and imaging method of the present invention reduce the cost of the imaging system by using a single detector 20 to receive rays of different energies emitted by the multi-energy ray source 10. Furthermore, by arranging the first ray source 11 and the second ray source 12 along the rotation plane of the multi-energy ray source 10, and alternately emitting rays of first energy 111 and second energy 121, the second ray source 12 at T... 2n-1 The position at time T0 coincides with the position of the first X-ray source 11 at time T0, where n is a natural number, to achieve data acquisition of the first energy 111 and the second energy 121 from the same angle of the X-ray source. By fixing a filter device 30 on the side of the first X-ray source 11 emitting relatively high energy toward the detector 20, the multi-energy imaging system 100 has a better ability to separate the high-energy and low-energy X-ray spectra.

[0067] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A multi-energy imaging system, characterized in that: It includes a multi-energy X-ray source and a single detector. The multi-energy X-ray source generates X-rays for projection imaging and rotates circumferentially along the detector. It includes a first X-ray source and a second X-ray source, which are arranged along the rotation plane of the multi-energy X-ray source and alternately emit X-rays of first energy and second energy. The second X-ray source is located at T... 2n-1 The position at time T0 coincides with the position of the first ray source at time T0, where n is a natural number; Each detector alternately receives and images rays of a first energy emitted by the first radiation source and rays of a second energy emitted by the second radiation source.

2. The multi-energy imaging system according to claim 1, characterized in that: The positional relationship between the first radiation source and the second radiation source satisfies the equation 2*D*sin(s*(2n-1)*t / 2)=d, Where d is the focal distance between the first and second X-ray sources, D is the rotation radius of the multi-energy X-ray source, s is the rotation angular velocity of the multi-energy X-ray source, n is a natural number, and t is the exposure time interval.

3. The multi-energy imaging system according to claim 1, characterized in that: The first energy is greater than the second energy, and a filter device is provided between the first radiation source and the detector. The filter device is located close to the first radiation source and remains relatively stationary with respect to the first radiation source.

4. The multi-energy imaging system according to claim 1, characterized in that: The multi-energy imaging system further includes an image acquisition and processing unit, which performs virtual single-energy imaging on the rays emitted by the first ray source and the second ray source at the same location received by the detector.

5. The multi-energy imaging system according to claim 4, characterized in that: Before performing virtual monoenergetic imaging on the radiation emitted by the second radiation source, the image acquisition and processing unit performs virtual monoenergetic imaging on the second radiation source at T... 2n-1 The projection data at time T0 is rearranged to correspond with the projection data of the first ray source at time T0, and the effective data range of the virtual monoenergetic imaging is the sum of the projection data of the first ray source at time T0 and the projection data of the second ray source at time T0. 2n-1 The overlapping portion of the projected data at any given time.

6. An imaging method, characterized in that, The application of the multi-energy imaging system according to any one of claims 1-5 includes the following steps: S1: The first and second radiation sources are arranged along the rotation plane of the multi-energy radiation source and alternately emit radiation of first and second energy. The second radiation source is located at T... 2n-1 The position at time T0 coincides with the position of the first ray source at time T0, where n is a natural number; S2: A single detector alternately receives rays of first energy emitted by the first radiation source and rays of second energy emitted by the second radiation source and images them respectively; S3: The image acquisition and processing unit performs virtual monoenergetic imaging on the rays emitted by the first ray source and the second ray source at the same position received by the detector.

7. The imaging method according to claim 6, characterized in that: The positional relationship between the first radiation source and the second radiation source satisfies the equation 2*D*sin(s*(2n-1)*t / 2)=d, Where d is the focal distance between the first and second X-ray sources, D is the rotation radius of the multi-energy X-ray source, s is the rotation angular velocity of the multi-energy X-ray source, n is a natural number, and t is the exposure time interval.

8. The imaging method according to claim 6, characterized in that: Before performing virtual monoenergetic imaging on the rays emitted by the first and second ray sources at the same position, the image acquisition and processing unit first rearranges the projection data of the first / second ray source so that it corresponds to the projection data of the second / first ray source.

9. The imaging method according to claim 8, characterized in that: The projection data of the first ray source at time T0 is: The second radiation source is in T 2n-1 The projection data at time is The image acquisition and processing unit will place the second ray source at T 2n-1 Time projection data Rearranged to the corresponding time T0 The method is as follows: Where d is the focal distance between the first and second radiation sources, L is the distance from the center point of the line connecting the first and second radiation sources to the detector, and θ is the distance from the detector at time T0 to T... 2n-1 The angle of rotation at any given moment.

10. The imaging method according to claim 9, characterized in that: The effective data range of the virtual monoenergetic imaging is the projection data of the first X-ray source at time T0 and the projection data of the second X-ray source at time T0. 2n-1 The overlapping portion of the projected data at any given time.

Images