Radiation imaging apparatus, CT imaging apparatus, and methods thereof

Abstract

The invention provides radiation imaging equipment, CT imaging equipment, a radiation imaging method and a CT imaging method. A radiation imaging device includes a radiation source, a detector, and at least one grating disposed between an inspection channel defined by the radiation source and the detector between the radiation source and the detector. And the grating only shields one part of the radiation beam, so that one part of the radiation beam passes through the grating and then is received by the detector.

Description

Technical Field

[0001] The present invention relates to the field of detection technologies. Specifically, it relates to a radiation imaging device, a CT imaging device, and their methods. Background Art

[0002] Existing X-ray CT imaging devices are usually based on traditional X-ray absorption imaging. Their core components are an X-ray source and a detector, and they can obtain an absorption image reflecting the attenuation characteristics of X-rays passing through substances. This absorption image has significant identification ability for substances with high density and strong X-ray absorption ability, and has significant imaging effects on substances such as metals and bones. Therefore, it has good utility in identifying contraband in the security inspection field and diagnosing bone diseases in the medical field. However, for substances composed of light elements (such as carbon, hydrogen, oxygen, nitrogen, etc.), the signals in the absorption image are weak, so there are great limitations. For example, it is difficult to observe contraband such as drugs blocked by metals in the security inspection field, and it is difficult to observe diseased tissues in the lungs in the medical field. Generally speaking, in order to improve the effects of security inspection and medical diagnosis, new technologies and new products that help improve the image identification ability of weakly absorbing substances should be explored. Summary of the Invention

[0003] According to one aspect of the present invention, there is provided a radiation imaging device, including:

[0004] A radiation source configured to emit a radiation beam;

[0005] A detector configured to receive the radiation beam from the radiation source, and the radiation source and the detector define an inspection channel; and

[0006] At least one grating arranged in the inspection channel between the radiation source and the detector;

[0007] Wherein, the at least one grating is configured such that a part of the radiation beam passes through the at least one grating before being received by a first part of the detector, while another part of the radiation beam is received by a second part of the detector and does not pass through the at least one grating.

[0008] In one embodiment, the first part of the detector includes a high-energy detector, and the second part of the detector includes a low-energy detector.

[0009] In one embodiment, the radiation imaging device is configured to at least construct 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.

[0010] In one embodiment, the at least one grating includes a periodic structure configured to diffract a radiation beam passing through the periodic structure to form an interference pattern.

[0011] 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.

[0012] In one embodiment, the at least one grating includes:

[0013] A first grating, the first grating being disposed adjacent to and parallel to the detector, spaced apart by a first distance from each other, and a radiation beam irradiates an object to be inspected after passing through the first grating; and / or

[0014] A second grating, the second grating being disposed adjacent to and parallel to the detector, spaced apart by a second distance from each other, the second distance being different from the first distance, and a radiation beam irradiates an object to be inspected after passing through the second grating; or the second grating is disposed adjacent to and parallel to the detector, spaced apart by a third distance from each other, and a radiation beam passes through the second grating after passing through the object to be inspected; and / or

[0015] A third grating, the third grating being disposed adjacent to and parallel to the detector, spaced apart by a fourth distance from each other, the fourth distance being different from the third distance, and a radiation beam passes through the third grating after passing through the object to be inspected.

[0016] In one embodiment, the radiation imaging device includes 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.

[0017] In one embodiment, the periodic structure of the grating is a channel type or a slit type.

[0018] 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 related to at least a partial region of an object to be inspected on an inspection channel based on signals detected by a detector.

[0019] In one embodiment, the at least one grating is a planar grating or a circular arc surface grating.

[0020] One aspect of the present invention provides a CT imaging device, including:

[0021] A rotating ring configured to be rotatable; and

[0022] The aforementioned radiation imaging device disposed on the rotating ring and rotating with the rotating ring.

[0023] One aspect of the present invention provides a radiation imaging method, including:

[0024] Imaging an object to be inspected using the above-mentioned radiation imaging device,

[0025] wherein the object to be inspected is moved on the inspection channel and sequentially passes through the first part and the second part of the detector, and at least one of an absorption image, a phase image, and a small-angle scattering image related to at least a partial region of the object to be inspected is generated based on the signals detected by the first part and the second part of the detector.

[0026] One aspect of the present invention provides a CT imaging method, including:

[0027] Imaging an object to be inspected using the above-mentioned CT imaging device,

[0028] wherein the object to be inspected is moved on the inspection channel and sequentially passes through the first part and the second part of the detector, 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 region of the object to be inspected is generated based on the signals detected by the first part and the second part of the detector.

[0029] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present invention, nor is it used to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. Description of the Drawings

[0030] The drawings are used to better understand the solution and do not constitute a limitation to the present invention, wherein:

[0031] Figure 1 Shows an example of the arrangement of the grating in the radiation imaging device.

[0032] Figure 2 Shows a radiation imaging device according to an embodiment of the present invention.

[0033] Figure 3 Shows a radiation imaging device according to another embodiment of the present invention.

[0034] Figure 4 Shows a radiation imaging device according to another embodiment of the present invention, wherein the detector includes two separate parts.

[0035] Figure 5 Shows two-dimensional images of absorption T(a), phase Φ(b), and small-angle scattering D(c), and XY plane slice images of three-dimensional images of 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 by rotating one week (corresponding to formula (3) in the disclosure).

[0036] Figure 6The microscopic images of tissue sections after staining of human breast specimens 1 - 6 (a1 - a6), and the corresponding sliced images of the linear attenuation coefficient μ after three - dimensional reconstruction in the XZ plane (b1 - b6), and the sliced images of the refractive index decrement δ after three - dimensional reconstruction in the XZ plane (c1 - c6) are shown. Detailed implementation manners

[0037] To more clearly elaborate the purpose, technical solution and advantages of the present invention, the embodiments of the present invention 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 invention, and should not be construed as a limitation to the present invention. In the specification and drawings, the same or similar reference numerals refer to the same or similar components or elements. For clarity, the drawings are not necessarily drawn to scale, and some well - known components and structures may be omitted in the drawings.

[0038] Unless otherwise defined, the technical terms or scientific terms used in the present invention should have the ordinary meanings understood by those of ordinary skill in the field to which the present invention pertains. The "first", "second" and similar terms used in the present invention do not denote any order, quantity or importance, but are only used to distinguish different components. The word "a" or "an" does not exclude a plurality. Words such as "including" or "comprising" mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connection" or "coupling" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Upper", "lower", "left", "right", "top" or "bottom", etc. are only used to represent relative position relationships. When the absolute position of the object being described changes, the relative position 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 can be "directly" on or under the other element, or there may be intermediate elements.

[0039] Figure 1 (a), (b), (c), (d) show various grating imaging arrangements, where G1, G2, G3 represent three gratings, which are respectively arranged Figure 1 as shown in (a), (b), (c), (d) between the source and the object to be inspected or between the object to be inspected and the detector.

[0040] In grating imaging technology, the wave - particle duality of X - rays can be utilized simultaneously, and three multi - characteristic information of absorption, phase and small - angle scattering can be obtained simultaneously. Among them, the absorption and phase information respectively correspond to the imaginary part β and the real part δ of the complex refractive index n:

[0041] n = 1 - δ + iβ (1)

[0042] where the linear attenuation coefficient μ has a linear relationship with the imaginary part β (λ is the wavelength of the X-ray):

[0043]

[0044] Absorbing three characteristic information of transmission T, phase Φ, and small-angle scattering D can be regarded as the integrals of the linear attenuation coefficient μ, refractive index decrement δ, and linear diffusion coefficient ζ respectively (where L is the propagation path of the X-ray, c Φ and c D are both constant values related to the imaging system):

[0045]

[0046] Considering that X-rays usually have an energy spectrum distribution, assuming the normalized energy spectrum distribution is S(E), then formula (3) can be written as:

[0047]

[0048] In Figure 1 (a), the function of grating G1 can be to form a self-imaging fringe image on the subsequent optical path. When X-rays interact with matter, this self-imaging fringe may undergo local distortion. This kind of distortion is at the micron or even sub-micron scale, and ordinary detectors cannot achieve such high resolution. Therefore, grating G2 amplifies this signal, and by observing the strength change of the detector signal, three multi-characteristic images of absorption, phase, and small-angle scattering can be extracted. When the X-ray source focus is small enough (such as synchrotron radiation or micro-focus X-ray machine), only gratings G1 and G2 are needed, as shown in Figure 1 (a), (c).

[0049] When the X-ray source focus size is large (such as a conventional X-ray machine), the resulting blurring effect will deteriorate the imaging effect. Therefore, a grating G0 is added behind the X-ray source. Due to grating G0, the radiation beam emitted by the X-ray source is converted into a series of partially coherent micron-scale linear radiation beams, as shown in Figure 1 (b), (d).

[0050] The object to be inspected W can be placed between grating G0 and grating G1( Figure 1 (b)), or it can also be placed between grating G1 and grating G2( Figure 1 (c), (d)).

[0051] When the object to be inspected W is placed between grating G0 and G1, as shown in Figure 1As shown in (b), the phase and small-angle scattering signals that can be obtained in this configuration are stronger, and the imaging contrast and sensitivity are higher. However, there are also disadvantages, that is, the area of grating G1 is large and the cost is high, and the X-rays passing through the object W need to be blocked by gratings G1 and G2 before being received by the detector, resulting in a low X-ray utilization rate.

[0052] When the object W is placed between gratings G1 and G2, as Figure 1 shown in (c) and (d), in this configuration, grating G1 is close to the light source, with a small area and low cost. The X-rays passing through the object W are only blocked by grating G2, and the X-ray utilization rate is higher. However, there are also disadvantages. The obtained phase and small-angle scattering signals are weakened, but this is not easy to cause detector signal saturation for some strongly scattering substances.

[0053] The absorption image (T above) reflects the attenuation characteristics of the substance to X-rays, corresponding to the imaginary part β of the complex refractive index of the substance in X-rays (complex refractive index n = 1 - δ + iβ); the phase image reflects the refraction effect of the substance to X-rays, corresponding to the real part δ of the complex refractive index of the substance in X-rays. Its beneficial effect is that for weakly absorbing substances, the contrast of the phase image is higher than that of the absorption image, and δ can be 2 to 3 orders of magnitude higher than β. Therefore, the weakly absorbing substances can be more clearly displayed through the phase image; the small-angle scattering image reflects the structural information of the mesoscopic size of the substance, and is very sensitive to the differences at the micron or submicron scale such as porosity and multi-fibers, and can break through the limitation of the resolution ability of absorption imaging. The phase and small-angle scattering images are good supplements to the absorption image, can effectively improve the overall imaging effect and resolution ability of the object W, and improve the adaptability and accuracy of the inspection process for different substances. Figure 5 Shows the absorption T (a), phase Φ (b) and small-angle scattering D (c) two-dimensional images, and the 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) reconstructed by the FBP algorithm after collecting 360 projections in one rotation (corresponding to formula (3) in the disclosure). The absorption image reflecting the attenuation characteristics of the substance (corresponding to the linear attenuation coefficient μ); the phase image with higher contrast for weakly absorbing substances (corresponding to the refractive index decrement δ in the complex refractive index), reflecting the texture information of the internal and external structures of the object W; and the small-angle scattering image reflecting the structural information of the mesoscopic scale of the substance (corresponding to the linear diffusion coefficient ζ), reflecting the microscopic structures such as porosity and multi-fibers at the micron / submicron scale.

[0054] Figure 6The microscopic images of tissue sections after staining of human breast specimens 1-6 (a1-a6), and the corresponding sectional images of the linear attenuation coefficient μ after three-dimensional reconstruction in the XZ plane (b1-b6), and the sectional images of the refractive index decrement δ after three-dimensional reconstruction in the XZ plane (c1-c6) are shown.

[0055] In specimens 1, 2, 4, and 5, the arrows indicate tumor lesions (deeply colored), in specimen 3, the arrow indicates pectoral muscle tissue, and in specimen 6, the arrow indicates the necrotic area (deeply colored).

[0056] Adipose tissue can be well distinguished in all sample images. However, in the reconstructed images of phase information, the distinction between the tumor region and the surrounding fibroglandular tissue is better, and the necrotic area can also be distinguished. Grating imaging advantageously complements the identification deficiencies of non-grating absorption two-dimensional imaging, enabling a more comprehensive analysis of the sample by combining the two.

[0057] As Figure 2 shown, 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, the radiation source S and the detector DT defining an inspection channel; and at least one grating disposed in the inspection channel between the radiation source S and the detector DT. The at least one grating is configured such that a part of the radiation beam passes through the at least one grating before being received by a first part DT-1 of the detector, while another part of the radiation beam is received by a second part DT-2 of the detector and does not pass through the at least one grating. In other words, as Figure 2 shown, a grating is provided upstream of the first part DT-1 of the detector, and the radiation beam from the radiation source S first passes through the grating and then is detected by the detector, while no grating is provided upstream of the second part DT-2 of the detector, and the radiation beam received by it does not pass through the grating. The radiation beam finally detected by the detector may pass through the object to be inspected W; the at least one grating may be one grating, two gratings, or as Figure 2 shown, three gratings, however, it should be understood that it is not necessary to provide three gratings upstream of a part of the detector as Figure 2 shown. Figure 2 Only one embodiment of the present disclosure is shown.

[0058] In an embodiment of the present disclosure, as Figure 2As shown, a part of the radiation beam emitted by the radiation source S (for example, the left part) passes through the gratings G0 and / or G1 and / or G2, while the other part (for example, the right part) does not pass through the gratings, and finally both are detected by the detector. According to this embodiment, advantageously, the radiation beam emitted by the same radiation source S can detect the same part of the object under inspection W with and without passing through the grating, which can ensure that the radiation beams irradiating the object under inspection W are basically the same, and there will be no differences or variations in the radiation beams caused by different radiation sources, resulting in systematic errors or even misjudgments in the inspection. In this embodiment, since the same radiation source S is used to irradiate the object under inspection W at the same time, and one part uses the grating while the other part does not, at least a part (for example, the part of interest) of the object under inspection W can obtain an absorption image, a two-dimensional phase image, and a two-dimensional small-angle scattering image when the object under inspection W passes through once. Thus, by comparing these acquired images, the properties and structures of, for example, biological tissues can be accurately judged.

[0059] In one embodiment, the detector may include two parts, for example, as Figure 2 shown, the first part DT-1 of the detector (such as the left part in Figure 2 ) includes a high-energy detector, and the second part DT-2 of the detector (such as the right part in Figure 2 ) 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 formed two-dimensional absorption image will more clearly reflect the properties of at least part of the object under inspection W. According to this embodiment, the inventor considered that the grating absorbs a certain amount of low-energy radiation energy, so part of the low-energy radiation beam does not reach the high-energy detector after passing through the grating, so that the high-energy detector can be less affected by the radiation beam of low-energy radiation energy, and the constructed two-dimensional high-energy absorption image more clearly reflects the internal structure of the object under inspection W, which is particularly significant for biological samples. At the same time, since the second part DT-2 of the detector is set as a low-energy detector, a two-dimensional low-energy absorption image constructed by the low-energy detector of the object under inspection W can be provided. The high-energy absorption image and the low-energy absorption image are combined to construct a comprehensive image with increased information, providing more comprehensive two-dimensional absorption image information.

[0060] The optical path part with a grating (including the first part DT-1 of the detector), when the X-ray beam penetrates the grating, the energy spectrum of the rays will be hardened due to the absorption effect of the grating, and the average energy of the rays will be increased. Absorption, phase, and small-angle scattering images can be obtained synchronously. At this time, the absorption image corresponds to the high-energy image in dual-energy imaging; the optical path part without a grating (including the first part DT-2 of the detector), the X-ray beam is directly absorbed by the second part DT-2 of the detector after penetrating the object. Compared with the first part DT-1 of the detector, the average energy of its 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.

[0061] On the one hand, the imaging system can achieve X-ray dual-energy imaging, that is, the high-energy absorption image of the first part DT-1 of the detector is combined with the low-energy absorption image of the second part DT-2 of the detector, and layered imaging of multiple materials can be obtained through material decomposition, which is beneficial to the material identification of the object to be inspected; on the other hand, the imaging system can achieve multi-characteristic imaging (DT-1). In addition to the traditional absorption image, it can also obtain a phase image with a higher contrast ratio than the absorption image, and a small-angle scattering image reflecting the microscopic structural characteristics of the object to be inspected. Based on the above imaging results, for example, X-ray comprehensive imaging can be achieved through appropriate software and image processing techniques.

[0062] In one embodiment, the first part DT-1 and the second part DT-2 of the detector are integrated, such as Figure 2 shown. In another embodiment, the first part DT-1 and the second part DT-2 of the detector are separate, such as Figure 3 shown.

[0063] In an 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 simultaneously; in this embodiment, the first part DT-1 and the second part DT-2 of the detector are integrated or can be separate.

[0064] 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 including multiple slits, that is to say, the periodic structure can be, for example, a slit; the periodic structure can be other structures rather than slits, for example, it can be a material capable of generating a fringe pattern, etc.; the periodic structure can be any periodic structure as long as it can generate an interference image or a moiré pattern after the radiation beam passes through. The grating can be a channel-type grating.

[0065] Taking the periodic structure as a slit as an example, the period direction of the periodic structure can be the arrangement direction of multiple slits, and the extension direction of a single sub-structure (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 with the inspection channel (the extension direction of the inspection channel, such as Figure 2 the direction indicated by the moving arrow of the object to be inspected W in, that is, the z direction), for example, when it is 10 -4 degrees, the interference fringes or Moiré fringes generated by the periodic structure formed by the arrangement of multiple slits will change greatly. Therefore, in the present disclosure, as long as the extension direction of a single slit and the inspection channel are set to form a very small angle, the requirements of the present invention can be met. In one embodiment, in Figure 2 , the radiation beam irradiation direction is the Y direction, the extension direction of the inspection channel is the Z direction, the moving direction of the object to be inspected W is the Z direction, and the extension direction of a single slit can be, for example, the transverse direction of 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 period direction of the periodic structure) is parallel to the extension direction of the inspection channel, and in Figure 2 it is horizontally arranged from left to right (Z direction). 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.

[0066] In one embodiment, the radiation imaging device includes a grating G0, which is adjacent to and parallel to the detector and spaced a first distance apart. The radiation beam irradiates the object to be inspected W after passing through the grating G0. In other words, the grating G0 is located upstream of the object to be inspected W.

[0067] In one embodiment, the radiation imaging device further includes a grating G1, which is different from the grating G0. That is to say, in this embodiment, two gratings G0 and G1 are provided. The grating G1 is adjacent to and parallel to the detector and spaced a second distance apart, and the second distance is not equal to the first distance. The radiation beam irradiates the object to be inspected W after passing through the grating G1. That is to say, the grating G1 is also located upstream of the object to be inspected W. In this embodiment, two gratings G0 and G1 are provided upstream of the object to be inspected W.

[0068] 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 to be inspected W. That is to say, the radiation beam first passes through the object to be inspected W and then passes through the grating G2. In this embodiment, the object to be inspected W passes between the grating G1 and the grating G2. In another embodiment, the object to be inspected W passes between the grating G0 and the grating G1, and both the grating G1 and the grating G2 are downstream of the object to be inspected 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.

[0069] In one embodiment of the invention, the grating may have a grating surface. In one embodiment, the grating may have an arc surface. Figure 4 An embodiment is shown where the gratings G0, G1, G2 are arc surfaces. Figure 4 For simplicity, only the part of the present invention including the grating is shown. In this embodiment, the detector may be as Figure 4 shown as an arc surface.

[0070] 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 be able to rotate. The imaging device further includes the aforementioned radiation imaging device disposed on the rotating ring and rotating with the rotating ring. By rotating the rotating ring, the radiation source can irradiate the object to be examined W from different angles, thereby different tomographic images can be obtained, and finally a three-dimensional image of the object to be examined W and a three-dimensional grating image can be constructed through computer processing. The CT imaging device may further include other components, such as a processor or an arithmetic unit, which will not be elaborated here.

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

[0072] imaging the object to be examined W using the aforementioned radiation imaging device,

[0073] wherein the object to be examined W is moved on the inspection channel and sequentially passes through the first part DT-1 and the second part DT-2 of the detector, and at least one of an absorption image, a phase image, and a small-angle scattering image related to at least a partial region of the object to be examined W is generated based on the signals detected by the first part DT-1 and the second part DT-2 of the detector.

[0074] According to one aspect of the present disclosure, a CT imaging method is provided, including:

[0075] imaging the object to be examined W using the aforementioned CT imaging device,

[0076] wherein the object to be examined W is moved on the inspection channel and sequentially passes through the first part DT-1 and the second part DT-2 of the detector, 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 region of the object to be examined W is generated based on the signals detected by the first part DT-1 and the second part DT-2 of the detector.

[0077] It should be understood that various forms of the processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in the present invention can be executed in parallel, sequentially, or in a different order, as long as the desired results of the technical solutions disclosed in the present invention can be achieved, and no limitations are imposed herein.

[0078] In the technical solution of the present disclosure, the collection, storage, use, processing, transmission, provision, and disclosure of the user's personal information and other processing all comply with the provisions of relevant laws and regulations and do not violate public order and good customs.

[0079] The above specific implementation manners do not constitute a limitation on the protection scope of the present invention. Those skilled in the art should understand that various modifications, combinations, sub - combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A radiation imaging device, comprising: A radiation source configured to emit a radiation beam; A detector configured to receive the radiation beam from the radiation source, the radiation source and the detector defining an inspection channel; And 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 part of the radiation beam passes through the at least one grating before being received by a first part of the detector, while another part of the radiation beam is received by a second part of the detector and does not pass through the at least one grating.

2. The radiation imaging device according to claim 1, wherein the first part of the detector comprises a high-energy detector and the second part of the detector comprises a low-energy detector.

3. The radiation imaging device according to claim 2, configured to construct at least 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 the 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 integral, 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, the first grating being disposed adjacent to and parallel to the detector, spaced apart by a first distance from each other, and the radiation beam irradiates the object to be inspected after passing through the first grating; And / or A second grating, the second grating being disposed adjacent to and parallel to the detector, spaced apart by a second distance from each other, the second distance being different from the first distance, and the radiation beam irradiates the object to be inspected after passing through the second grating; or the second grating is disposed adjacent to and parallel to the detector, spaced apart by a third distance from each other, and the radiation beam passes through the second grating after passing through the object to be inspected; and / or A third grating, the third grating being disposed adjacent to and parallel to the detector, spaced apart by a fourth distance from each other, the fourth distance being different from 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 channel-type or 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 region of the object to be inspected 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 planar grating or an arc-surface grating.

11. A CT imaging device, comprising: A rotating ring configured to be rotatable; and The radiation imaging device according to any one of claims 1-10, disposed on the rotating ring and rotating therewith.

12. A radiation imaging method, comprising: Imaging an object to be examined using the radiation imaging device according to any one of claims 1-10, wherein the object to be examined is moved on the inspection channel and sequentially passes through the first part and the second part of the detector, and at least one of an absorption image, a phase image, and a small-angle scattering image related to at least a partial region of the object to be examined is generated based on signals detected by the first part and the second part of the detector.

13. A CT imaging method, comprising: Imaging an object to be examined using the CT imaging device according to claim 11, wherein the object to be examined is moved on the inspection channel and sequentially passes through the first part and the second part of the detector, 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 region of the object to be examined is generated based on signals detected by the first part and the second part of the detector.

Images