Radiation imaging device, CT imaging device, and method thereof

Abstract

A radiation imaging device, a CT imaging device, a radiation imaging method, and a CT imaging method. The radiation imaging device comprises: a radiation source (S), a detector (DT), and at least one grating (G0, G1, G2), the at least one grating (G0, G1, G2) being arranged on an inspection channel defined between the radiation source (S) and the detector (DT). The grating (G0, G1, G2) shields only a portion of the radiation beam such that a portion of the radiation beam is received by the detector (DT) after passing through the grating (G0, G1, G2).

Description

Radiation imaging device, CT imaging device and method thereof

[0001] This application claims priority to Chinese patent application No. 202311774400.3 filed on December 21, 2023, the contents of which are incorporated herein by reference. Technical Field

[0002] The present disclosure relates to the field of detection technology, and in particular to a radiation imaging device, a CT imaging device, and a method thereof. Background Art

[0003] Related X-ray CT imaging equipment is usually implemented based on traditional X-ray absorption imaging. Its core components are X-ray sources and detectors, which can obtain absorption images that reflect the attenuation characteristics of X-rays passing through matter. This absorption image has significant recognition capabilities for materials with high density and strong X-ray absorption capabilities, and has significant imaging effects on materials such as metals and bones. Therefore, it has good effectiveness in identifying contraband in the security field and diagnosing bone diseases in the medical field. However, for materials composed of light elements (carbon, hydrogen, oxygen, nitrogen, etc.), the signal in the absorption image is weak, and therefore has great limitations. For example, it is difficult to observe contraband such as drugs obscured by metal in the security field, and it is difficult to observe pathological lung tissue in the medical field. Overall, in order to improve the effectiveness of security inspections and medical diagnoses, new technologies and products that help improve the image recognition capabilities of weakly absorbing materials should be explored. Summary of the Invention

[0004] According to one aspect of the present disclosure, there is provided a radiation imaging device, comprising:

[0005] a radiation source configured to emit a radiation beam;

[0006] a detector configured to receive a radiation beam from the radiation source, the radiation source and the detector defining an examination channel; and

[0007] at least one grating disposed on the inspection channel between the radiation source and the detector;

[0008] wherein the at least one grating is configured such that a portion of the radiation beam passes through the at least one grating before being received by the first portion of the detector, while another portion of the radiation beam is received by the second portion of the detector without passing through the at least one grating.

[0009] In one embodiment, the first portion of the detector comprises a high energy detector and the second portion of the detector comprises a low energy detector.

[0010] In one embodiment, the radiation imaging device is configured to construct at least a low-energy absorption image based on the radiation beam signals collected by the low-energy detector, construct a high-energy absorption image based on the radiation beam signals collected by the high-energy detector, and combine the high-energy absorption image with the low-energy absorption image to construct a comprehensive image with increased information.

[0011] In one embodiment, the at least one grating comprises a periodic structure configured to diffract a radiation beam passing through the periodic structure to form an interference pattern.

[0012] In one embodiment, the first part and the second part of the detector are integral, or the first part and the second part of the detector are separate.

[0013] In one embodiment, the at least one grating comprises:

[0014] a first grating, the first grating being arranged adjacent to and parallel to the detector and spaced a first distance apart from the detector, and the radiation beam irradiates the object after passing through the first grating; and / or

[0015] a second grating, wherein the second grating is arranged adjacent to and parallel to the detector, and is spaced apart from each other by a second distance, the second distance being different from the first distance, and the radiation beam irradiates the object after passing through the second grating; or the second grating is arranged adjacent to and parallel to the detector, and is spaced apart from each other by a third distance, and the radiation beam passes through the object before passing through the second grating; and / or

[0016] A third grating is arranged adjacent to and parallel to the detector and spaced apart by a fourth distance, wherein the fourth distance is not equal to the third distance. The radiation beam passes through the object to be inspected and then passes through the third grating.

[0017] In one embodiment, a radiation imaging device comprises a first grating, a second grating, and a third grating, wherein the first grating, the second grating, and the third grating are parallel to each other.

[0018] In one embodiment, the periodic structure of the grating is channel-type or slit-type.

[0019] In one embodiment, the radiation imaging device is configured to generate at least one of an absorption image, a phase image, and a small-angle scattering image associated with at least a partial area of ​​the object on the inspection channel based on the signal detected by the detector.

[0020] In one embodiment, the at least one grating is a plane grating or an arcuate grating.

[0021] One aspect of the present disclosure provides a CT imaging device, comprising:

[0022] a rotating ring configured to rotate; and

[0023] The aforementioned radiation imaging device is arranged on the rotating ring and rotates along with the rotating ring.

[0024] One aspect of the present disclosure provides a radiation imaging method, comprising:

[0025] Use the above-mentioned radiation imaging equipment to image the object under test,

[0026] The object to be inspected is moved along the inspection channel and passes through the first part and the second part of the detector in sequence, and at least one of an absorption image, a phase image and a small-angle scattering image associated with at least a partial area of ​​the object to be inspected is generated based on the signals detected by the first part and the second part of the detector.

[0027] One aspect of the present disclosure provides a CT imaging method, comprising:

[0028] The above-mentioned CT imaging device is used to image the object under examination.

[0029] The object to be inspected is moved along the inspection channel and passes through the first part and the second part of the detector in sequence, and at least one of a three-dimensional absorption image, a phase image and a small-angle scattering image associated with at least a partial area of ​​the object to be inspected is generated based on the signals detected by the first part and the second part of the detector.

[0030] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present disclosure, nor are they intended to limit the scope of the present disclosure. Other features of the present disclosure will become readily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings are used to better understand the present solution and do not constitute a limitation of the present disclosure, wherein:

[0032] FIG1 shows an example of the arrangement of a grating in a radiation imaging device.

[0033] FIG2 shows a radiation imaging device according to an embodiment of the present disclosure.

[0034] FIG3 shows a radiation imaging device according to another embodiment of the present disclosure.

[0035] FIG4 shows a radiation imaging device according to another embodiment of the present disclosure, wherein the detector includes two separate parts.

[0036] Figure 5 shows the two-dimensional images of absorption T(a), phase Φ(b) and small-angle scattering D(c), and the corresponding XY plane slice images of the three-dimensional images of the linear attenuation coefficient μ(d), refractive index decrement δ(e), and linear diffusion coefficient ζ(f) obtained by collecting 360 projections in one rotation and reconstructing them using the FBP algorithm (corresponding to formula (3) in the briefing book).

[0037] FIG6 shows microscopic images (a1-a6) of stained tissue sections of human breast specimens 1-6, as well as corresponding slice images (b1-b6) of the linear attenuation coefficient μ in the XZ plane after 3D reconstruction and slice images (c1-c6) of the refractive index decrement δ in the XZ plane after 3D reconstruction. DETAILED DESCRIPTION

[0038] To more clearly illustrate the objectives, technical solutions, and advantages of the present disclosure, embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the following description of the embodiments is intended to explain and illustrate the overall concept of the present disclosure and should not be construed as limiting the present disclosure. In the specification and drawings, the same or similar reference numerals refer to the same or similar parts or components. For the sake of clarity, the drawings are not necessarily drawn to scale, and some well-known parts and structures may be omitted in the drawings.

[0039] Unless otherwise defined, technical or scientific terms used in this disclosure should have the ordinary meaning understood by a person of ordinary skill in the art to which this disclosure belongs. The terms "first," "second," and similar terms used in this disclosure do not denote any order, quantity, or importance, but are simply used to distinguish different components. The terms "a" or "an" do not exclude a plurality. Terms such as "include" or "comprise" mean that the element or object preceding the term includes the elements or objects listed after the term and their equivalents, but do not exclude other elements or objects. Terms such as "connected" or "connected" are not limited to physical or mechanical connections but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," "right," "top," or "bottom" are used only to indicate relative positional relationships; if the absolute position of the described objects changes, the relative positional relationship may also change accordingly. When an element such as a layer, film, region, or substrate is referred to as being "on" or "under" another element, the element may be "directly" "on" or "under" the other element, or intervening elements may be present.

[0040] Figures 1(a), (b), (c), and (d) show various grating imaging arrangements, where G1, G2, and G3 represent three gratings, which are arranged between the source and the object under test or between the object under test and the detector as shown in Figures 1(a), (b), (c), and (d), respectively.

[0041] In grating imaging technology, the wave and particle properties of X-rays can be simultaneously utilized to obtain three multi-characteristic information: absorption, phase, and small-angle scattering. The absorption and phase information correspond to the imaginary part β and real part δ of the complex refractive index n, respectively: n = 1-δ + iβ (1)

[0042] The linear attenuation coefficient μ is linearly related to the imaginary part β (λ is the wavelength of the X-ray):

[0043] The three characteristic information of absorption T, phase Φ and small-angle scattering D can be regarded as the integral of linear attenuation coefficient μ, refractive index decrement δ, and linear diffusion coefficient ζ respectively (where L is the propagation path of X-rays, c Φ and c D are all constant values ​​related to the imaging system):

[0044] Considering that X-rays usually have an energy spectrum distribution, assuming that the normalized energy spectrum distribution is S(E), formula (3) can be written as:

[0045] In Figure 1(a), grating G1 forms a self-imaging fringe pattern on its trailing optical path. When X-rays interact with matter, these self-imaging fringes may undergo local distortion. This distortion occurs on the micron or even submicron scale, a level beyond the resolution of conventional detectors. Therefore, grating G2 amplifies this signal and, by observing variations in the detector signal, extracts three multi-characteristic images: absorption, phase, and small-angle scattering. When the X-ray source's focal point is sufficiently small (e.g., synchrotron radiation or microfocus optical systems), only gratings G1 and G2 are required, as shown in Figures 1(a) and 1(c).

[0046] When the focal spot size of the X-ray source is large (such as a conventional X-ray machine), the blurring effect it brings will lead to poor imaging quality. Therefore, a grating G0 is added after the X-ray source. Due to the grating G0, the radiation beam emitted by the X-ray source is converted into a series of partially coherent micron-level linear radiation beams, as shown in Figure 1(b) and (d).

[0047] The object W can be placed between the grating G0 and the grating G1 ( FIG. 1( b ) ), or between the grating G1 and the grating G2 ( FIG. 1( c ) and ( d ) ).

[0048] When the object W is placed between gratings G0 and G1, as shown in Figure 1(b), the phase and small-angle scattering signals obtained in this configuration are stronger, and the imaging contrast and sensitivity are higher. However, there are also disadvantages, namely, the large area and high cost of grating G1, and the X-rays after passing through the object W need to be blocked by gratings G1 and G2 before they can be received by the detector, resulting in low X-ray utilization.

[0049] When the object W is placed between gratings G1 and G2, as shown in Figures 1(c) and (d), in this configuration, grating G1 is close to the light source, has a small area and low cost, and the X-rays passing through the object W are only blocked by grating G2, which increases the X-ray utilization rate. However, it also has disadvantages. The obtained phase and small-angle scattering signals are weakened. However, for some strongly scattering materials, this is not likely to cause detector signal saturation.

[0050] The absorption image (T above) reflects the material's attenuation characteristics for X-rays and corresponds to the imaginary part of the material's complex refractive index, β (complex refractive index n = 1-δ + iβ). The phase image reflects the material's refractive effect on X-rays and corresponds to the real part of the material's complex refractive index, δ. This has the beneficial effect of providing higher contrast for weakly absorbing materials than the absorption image, with δ being 2 to 3 orders of magnitude higher than β. Therefore, weakly absorbing materials can be more clearly visualized using the phase image. The small-angle scattering image reflects the material's mesoscopic structural information and is highly sensitive to micron or submicron differences in porosity and fibrous structures, potentially overcoming the limitations of absorption imaging resolution. Phase and small-angle scattering images complement the absorption image, effectively improving the overall imaging quality and resolution of the object under test, W, and enhancing the adaptability and accuracy of the inspection process for different materials. Figure 5 shows two-dimensional images of absorption T (a), phase Φ (b), and small-angle scattering D (c), along with corresponding XY plane slice images of the linear attenuation coefficient μ (d), refractive index decrement δ (e), and linear diffusion coefficient ζ (f), reconstructed using the FBP algorithm after collecting 360 projections during one rotation (corresponding to formula (3) in the handout). The absorption image (corresponding to the linear attenuation coefficient μ) reflects the attenuation characteristics of the material; the phase image (corresponding to the refractive index decrement δ in the complex refractive index) with higher contrast for weakly absorbing materials reflects the texture information of the internal and external structures of the object under test W; and the small-angle scattering image (corresponding to the linear diffusion coefficient ζ) reflects the mesoscopic structural information of the material, reflecting microstructures such as porosity and multi-fibers at the micron / submicron scale.

[0051] FIG6 shows microscopic images (a1-a6) of stained tissue sections of human breast specimens 1-6, as well as corresponding slice images (b1-b6) of the linear attenuation coefficient μ in the XZ plane after 3D reconstruction and slice images (c1-c6) of the refractive index decrement δ in the XZ plane after 3D reconstruction.

[0052] The arrows in specimens 1, 2, 4, and 5 indicate tumor lesions (dark color in the center), the arrow in specimen 3 indicates pectoral muscle tissue, and the arrow in specimen 6 indicates necrotic areas (dark color in the center).

[0053] Fat tissue was well distinguished in all sample images, but phase-reconstructed images showed better differentiation between the tumor region and surrounding fibroglandular tissue, and were also able to distinguish necrotic areas. Grating imaging advantageously complements the identification deficiencies of absorption 2D imaging without grating, enabling a more comprehensive analysis of the sample through a combination of the two.

[0054] As shown in FIG2 , according to an embodiment of the present disclosure, a radiation imaging device includes: a radiation source S configured to emit a radiation beam; a detector DT configured to receive the radiation beam from the radiation source S, wherein the radiation source S and the detector DT define an inspection channel; and at least one grating disposed on the inspection channel between the radiation source S and the detector DT. The at least one grating is configured such that a portion of the radiation beam passes through the at least one grating before being received by the first portion DT-1 of the detector, while another portion of the radiation beam is received by the second portion DT-2 of the detector without passing through the at least one grating. In other words, as shown in FIG2 , a grating is provided upstream of the first portion DT-1 of the detector, and the radiation beam from the radiation source S first passes through the grating and is then detected by the detector, while no grating is provided upstream of the second portion DT-2 of the detector, and the radiation beam received by the second portion DT-2 does not pass through the grating. Here, the radiation beam finally detected by the detector may be one that passes through the object W; the at least one grating may be one grating, two gratings, or three gratings as shown in FIG2 . However, it should be understood that it is not necessary to provide three gratings upstream of a part of the detector as shown in FIG2 . FIG2 shows only one embodiment of the present disclosure.

[0055] In one embodiment of the present disclosure, as shown in FIG2 , a portion (e.g., the left portion) of the radiation beam emitted by a radiation source S passes through gratings G0 and / or G1 and / or G2, while another portion (e.g., the right portion) does not pass through the gratings, and ultimately both are detected by the detector. Advantageously, according to this embodiment, the radiation beam emitted by the same radiation source S detects the same portion of the object W when passing through the gratings and when not passing through the gratings, thereby ensuring that the radiation beam irradiating the object W is substantially the same, and preventing differences or variations in the radiation beams due to different radiation sources from causing systematic errors or even misjudgments in the inspection. In this embodiment, because the same radiation source S is used to irradiate the object W simultaneously, and a portion uses the gratings while another portion does not, an absorption image, a two-dimensional phase image, and a two-dimensional small-angle scattering image of at least a portion (e.g., the portion of interest) of the object W can be obtained during a single pass of the object W. Thus, by comparing these acquired images, it is possible to accurately determine, for example, the properties and structure of, in particular, biological tissue.

[0056] In one embodiment, the detector can include two parts. For example, as shown in FIG2 , the first part DT-1 (the left part of FIG2 ) includes a high-energy detector, and the second part DT-2 (the right part of FIG2 ) includes a low-energy detector. In this embodiment, since the radiation beam passing through the grating is detected by the high-energy detector, and the radiation beam not passing through the grating is detected by the low-energy detector, the resulting two-dimensional absorption image more clearly reflects at least some of the properties of the object W. According to this embodiment, the inventors consider that the grating absorbs some low-energy radiation energy to a certain extent. Therefore, a portion of the low-energy radiation beam does not reach the high-energy detector after passing through the grating. This reduces the impact of the low-energy radiation on the high-energy detector. The resulting high-energy absorption two-dimensional image more clearly reflects the internal structure of the object W, which is particularly significant for biological samples. Furthermore, since the second part DT-2 of the detector is a low-energy detector, a low-energy absorption two-dimensional image of the object W, generated by the low-energy detector, can be provided. The high-energy absorption image and the low-energy absorption image are combined to create a comprehensive image with increased information, providing more comprehensive absorption two-dimensional image information.

[0057] In the optical path portion with a grating (including the first part of the detector DT-1), when the X-ray beam penetrates the grating, the absorption effect of the grating will harden the energy spectrum of the rays, and the average energy of the rays will be increased, so that absorption, phase and small-angle scattering images can be obtained simultaneously. At this time, the absorption image corresponds to the high-energy image in dual-energy imaging. In the optical path portion without a grating (including the first part of the detector DT-2), the X-ray beam penetrates the object and is directly absorbed by the second part of the detector DT-2. Compared with the first part of the detector DT-1, the average energy of the rays is lower, and an absorption image can be obtained. At this time, the absorption image corresponds to the low-energy image in dual-energy imaging.

[0058] On the one hand, the imaging system can achieve dual-energy X-ray imaging, that is, combining the high-energy absorption image of the first part of the detector DT-1 with the low-energy absorption image of the second part of the detector DT-2, and obtaining layered imaging of multiple materials through material decomposition, which is conducive to the material identification of the object being inspected. On the other hand, the imaging system can achieve multi-characteristic imaging (DT-1). In addition to traditional absorption images, it can also obtain phase images with higher contrast than absorption images, as well as small-angle scattering images that reflect the microstructural characteristics of the object being inspected. Based on the above imaging results, X-ray comprehensive imaging can be achieved, for example, through appropriate software and image processing technology.

[0059] In one embodiment, the first portion DT-1 and the second portion DT-2 of the detector are integrated, as shown in FIG2 . In another embodiment, the first portion DT-1 and the second portion DT-2 of the detector are separated, as shown in FIG3 .

[0060] In one embodiment of the present disclosure, the first part DT-1 and the second part DT-2 of the detector DT are the same detector, that is, a high-energy detector and / or a low-energy detector are used at the same time; in this embodiment, the first part DT-1 and the second part DT-2 of the detector are integrated, or can be split.

[0061] According to an embodiment of the present disclosure, at least one grating includes a periodic structure configured to diffract a radiation beam passing through the periodic structure to form an interference pattern. The grating can be a grating comprising a plurality of slits, that is, the periodic structure can be, for example, slits; the periodic structure can be other structures other than slits, such as a material capable of producing a fringe pattern; and the periodic structure can be any periodic structure capable of producing an interference pattern or moiré pattern after a radiation beam passes through the structure. The grating can be a channel grating.

[0062] Taking the periodic structure as a slit as an example, the periodic direction of the periodic structure can be the arrangement direction of the multiple slits, and the extension direction of a single substructure (such as a slit) of the periodic structure is perpendicular to the arrangement direction of the multiple slits. According to the present disclosure, when the extension direction of a single slit forms a very small angle (for example, relative to the case of being parallel to the inspection channel) with the extension direction of the inspection channel (the extension direction of the inspection channel, such as the direction shown by the arrow of the object W moving in FIG. 2, that is, the z direction), for example 10 -4 When the angle of the periodic structure is changed, the interference fringes or moiré fringes produced by the periodic structure composed of the arrangement of multiple slits will change significantly. Therefore, in the present disclosure, as long as the extension direction of a single slit is set to a very small angle with the inspection channel, the requirements of the present disclosure can be met. In one embodiment, in FIG2 , the irradiation direction of the radiation beam is the Y direction, the extension direction of the inspection channel is the Z direction, and the moving direction of the object W under inspection is the Z direction. The extension direction of a single slit can be, for example, transverse to the extension direction of the inspection channel (i.e., perpendicular to the inspection channel). At this time, the arrangement direction of the slits (i.e., the periodic direction of the periodic structure) is parallel to the extension direction of the inspection channel, and is horizontally arranged from left to right (Z direction) in FIG2 . In other embodiments, the extension direction of a single slit can be, for example, a non-zero angle with the extension direction of the inspection channel.

[0063] In one embodiment, the radiation imaging device includes a grating G0 , which is arranged adjacent to and parallel to the detector and spaced a first distance apart from the detector. The radiation beam passes through the grating G0 and then irradiates the object W. In other words, the grating G0 is located upstream of the object W.

[0064] In one embodiment, the radiation imaging device further includes a grating G1, which is different from the grating G0. That is, in this embodiment, two gratings G0 and G1 are provided. The gratings G1 are arranged adjacent to and parallel to the detector, separated from each other by a second distance, which is not equal to the first distance. The radiation beam passes through the grating G1 and then irradiates the object W. That is, the grating G1 is also located upstream of the object W. In this embodiment, the two gratings G0 and G1 are provided upstream of the object W.

[0065] In one embodiment, the radiation imaging device includes a grating G0, a grating G1, and a grating G2. In this embodiment, the grating G2 is located downstream of the object W, that is, the radiation beam first passes through the object W and then passes through the grating G2. In this embodiment, the object W passes between the grating G1 and the grating G2. In another embodiment, the object W passes between the grating G0 and the grating G1, and both the grating G1 and the grating G2 are downstream of the object W. The fourth distance between the grating G2 and the detector is different from the second or third distance between the grating G1 and the detector.

[0066] In one embodiment of the invention, the grating may have a grating surface. In one embodiment, the grating may have an arcuate surface. Figure 4 illustrates an embodiment in which gratings G0, G1, and G2 are arcuate surfaces. For simplicity, Figure 4 only shows the portion of the present disclosure that includes the gratings. In this embodiment, the detector may have an arcuate surface, as shown in Figure 4.

[0067] According to one aspect of the present disclosure, a CT imaging device is provided. In this embodiment, the CT imaging device includes a rotating ring configured to rotate. The imaging device also includes the aforementioned radiation imaging device, which is arranged on the rotating ring and rotates with the rotating ring. Through the rotation of the rotating ring, the radiation source can irradiate the object W from different angles, thereby obtaining images of different slices, and ultimately constructing a three-dimensional image and a grating three-dimensional image of the object W through computer processing. The CT imaging device may also include other components, such as a processor or an operator, which are not described in detail here.

[0068] According to one aspect of the present disclosure, there is provided a radiation imaging method, comprising:

[0069] The above-mentioned radiation imaging device is used to image the object W.

[0070] The object W is moved along the inspection channel and passes through the first part DT-1 and the second part DT-2 of the detector in sequence, and at least one of an absorption image, a phase image and a small-angle scattering image related to at least a partial area of ​​the object W is generated based on the signals detected by the first part DT-1 and the second part DT-2 of the detector.

[0071] According to one aspect of the present disclosure, a CT imaging method is provided, comprising:

[0072] The above-mentioned CT imaging device is used to image the object W.

[0073] The object W is moved along the inspection channel and passes through the first part DT-1 and the second part DT-2 of the detector in sequence, and based on the signals detected by the first part DT-1 and the second part DT-2 of the detector, at least one of a three-dimensional absorption image, a phase image and a small-angle scattering image related to at least a partial area of ​​the object W is generated.

[0074] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this disclosure can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solutions disclosed in this disclosure can be achieved. This is not limited herein.

[0075] In the technical solutions disclosed herein, the collection, storage, use, processing, transmission, provision and disclosure of user personal information involved comply with the provisions of relevant laws and regulations and do not violate public order and good morals.

[0076] The above specific embodiments do not constitute a limitation on the scope of protection of this disclosure. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this disclosure shall be included within the scope of protection of this disclosure.

Claims

1. A radiation imaging device, comprising: a radiation source configured to emit a radiation beam; a detector configured to receive a radiation beam from the radiation source, the radiation source and the detector defining an inspection channel; as well as at least one grating disposed on the inspection channel between the radiation source and the detector; wherein the at least one grating is configured such that a portion of the radiation beam passes through the at least one grating before being received by the first portion of the detector, while another portion of the radiation beam is received by the second portion of the detector without passing through the at least one grating. 2 . The radiation imaging device according to claim 1 , wherein the first portion of the detector comprises a high-energy detector and the second portion of the detector comprises a low-energy detector.

3. The radiation imaging device according to claim 2 is configured to at least construct a low-energy absorption image based on the radiation beam signal collected by the low-energy detector, construct a high-energy absorption image based on the radiation beam signal collected by the high-energy detector, and combine the high-energy absorption image with the low-energy absorption image to construct a comprehensive image with increased information.

4. The radiation imaging device according to claim 3, wherein the at least one grating comprises a periodic structure configured to diffract a radiation beam passing through the periodic structure to form an interference pattern. 5 . The radiation imaging device according to claim 1 , wherein the first part and the second part of the detector are integrated, or the first part and the second part of the detector are separate.

6. The radiation imaging device according to claim 1, wherein the at least one grating comprises: a first grating, wherein the first grating is arranged adjacent to and parallel to the detector and is spaced a first distance apart from the detector, and the radiation beam irradiates the object to be inspected after passing through the first grating; and / or a second grating, the second grating is arranged adjacent to and parallel to the detector, the second distance is not equal to the first distance, and the radiation beam irradiates the object after passing through the second grating; or the second grating is arranged adjacent to and parallel to the detector, the third distance is separated from each other, and the radiation beam passes through the object and then passes through the second grating; and / or A third grating is arranged adjacent to and parallel to the detector and is spaced apart by a fourth distance, wherein the fourth distance is not equal to the third distance, and the radiation beam passes through the third grating after passing through the object to be inspected.

7. The radiation imaging device according to claim 7, comprising a first grating, a second grating and a third grating, wherein the first grating, the second grating and the third grating are parallel to each other.

8. The radiation imaging device according to claim 1, wherein the periodic structure of the grating is a channel type or a slit type.

9. The radiation imaging device according to claim 1, configured to generate at least one of an absorption image, a phase image and a small-angle scattering image related to at least a partial area of ​​the object under inspection on the inspection channel based on the signal detected by the detector.

10. The radiation imaging device according to claim 1, wherein the at least one grating is a plane grating or an arc grating.

11. A CT imaging device, comprising: a rotating ring configured to rotate; and The radiation imaging device according to any one of claims 1 to 10 is arranged on the rotating ring and rotates with the rotating ring.

12. A radiation imaging method, comprising: Using the radiation imaging device according to any one of claims 1 to 10 to image the object under inspection, The object to be inspected is moved along the inspection channel and passes through the first part and the second part of the detector in sequence, and at least one of an absorption image, a phase image and a small-angle scattering image related to at least a partial area of ​​the object to be inspected is generated based on the signals detected by the first part and the second part of the detector.

13. A CT imaging method, comprising: Using the CT imaging device according to claim 11 to image the object under examination, The object to be inspected is moved along the inspection channel and passes through the first part and the second part of the detector in sequence, and at least one of a three-dimensional absorption image, a phase image and a small-angle scattering image related to at least a partial area of ​​the object to be inspected is generated based on the signals detected by the first part and the second part of the detector.

Images