Energy-adjustable gamma ray sector source generation device and method

Abstract

The invention discloses an energy-adjustable gamma ray sector source generation device and method, and solves the problem that complete and clear images of different areas of a complex object are difficult to quickly acquire only by means of low-energy X rays or high-energy gamma rays. Through the arrangement of the first-stage collimation shielding body, the first-stage scatterer and the second-stage collimation shielding body, continuous adjustment of gamma ray source energy can be achieved under the condition that a radioactive source is not replaced, meanwhile, the fan-shaped radiation notch is formed in the end face of the plastic shielding body, so that an energy-adjustable gamma ray fan-shaped source is generated, and the energy-adjustable gamma ray fan-shaped source is formed through combination of the first-stage collimation shielding body, the first-stage scatterer and the second-stage collimation shielding body. Complete and clear images of different areas of a complex object can be rapidly obtained.

Description

Technical Field

[0001] The present invention relates to a gamma-ray generating device and method, and particularly to an adjustable energy gamma-ray fan beam source generating device and method. Background Art

[0002] Based on the study of the interaction between ray beams and substances and industrial detection technology, the internal structure of an object to be imaged can be inversely solved from its projection under non-contact and non-destructive conditions to obtain the required image. The object to be imaged usually has a small density and a small change range, and there is no need to perform high-definition imaging on high-density substances. The ray source generally uses a collimated low-energy X-ray plane source. However, the objects of industrial detection have a wide range, and the material densities of parts are generally large, so a collimated higher-energy gamma-ray plane source is generally used.

[0003] With the development of science and technology, imaging of complex objects composed of multiple parts has become a new requirement for industrial detection. The density change range of substances contained in complex objects is large, and it is impossible to form a complete and clear image only relying on low-energy X-rays or high-energy gamma-rays. Therefore, ray sources with multiple energies must be used for separate imaging to obtain clear images of different regions. Currently, gamma-rays with multiple energies mainly come from radionuclides, which require long nuclide lifetimes and relatively single energy points. However, there are few such radionuclides, and only 4 are commonly used in industrial detection: 137 Cs, 60 Co, 241 Am, and 133 Ba, and the available gamma-ray energy points are very limited. Therefore, there is an urgent need to develop an adjustable energy gamma-ray plane source. Summary of the Invention

[0004] In order to solve the technical problem that it is difficult to quickly obtain complete and clear images of different regions of complex objects only relying on low-energy X-rays or high-energy gamma-rays, the present invention provides an adjustable energy gamma-ray fan beam source generating device and method.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] An adjustable energy gamma-ray fan beam source generating device, characterized in that:

[0007] It includes a gamma-ray source, a first-stage collimation and shielding body, a first-stage scatterer, a second-stage collimation and shielding body, a second-stage scatterer, a shaping and shielding body, and a driving mechanism;

[0008] The gamma-ray source is located outside the entrance of the first-stage collimation and shielding body and is used for emitting gamma-rays;

[0009] The first-stage scatterer is located between the exit of the first-stage collimation and shielding body and the entrance of the second-stage collimation and shielding body;

[0010] The shaping shielding body is arranged outside the exit end of the secondary collimating shielding body. The end face of its incident end is in close contact with the end face of the exit end of the secondary collimating shielding body. A fan-shaped radiation notch for the emission of gamma rays is provided on the end face of its incident end; the incident opening of the radiation notch is communicated with the exit opening of the secondary collimating shielding body;

[0011] The secondary scatterer is located inside the incident opening of the radiation notch and corresponds to the exit opening of the secondary collimating shielding body;

[0012] The driving ends of the driving mechanism are respectively connected to the gamma-ray source and the primary collimating shielding body, and are used to drive the gamma-ray source and the primary collimating shielding body to rotate simultaneously around the center point of the primary scatterer, so as to change the energy of the gamma rays emitted from the radiation notch.

[0013] Furthermore, the primary collimating shielding body is cylindrical, its material is lead, and a cylindrical primary collimating channel penetrating through both ends thereof is provided inside;

[0014] The axis of the primary collimating channel coincides with the axis of the primary collimating shielding body, and its exit opening corresponds to the primary scatterer;

[0015] The gamma-ray source is located outside the incident opening of the primary collimating channel.

[0016] Furthermore, the secondary collimating shielding body is cylindrical, its material is lead, and a cylindrical secondary collimating channel penetrating through both ends thereof is provided inside;

[0017] The outer diameter of the secondary collimating shielding body is larger than the outer diameter of the primary collimating shielding body;

[0018] The axis of the secondary collimating channel coincides with the axis of the secondary collimating shielding body;

[0019] The primary scatterer is located outside the incident opening of the secondary collimating channel.

[0020] Furthermore, the shaping shielding body is cylindrical, and its material is lead;

[0021] The radiation notch includes a cylindrical notch and a fan-shaped cylindrical notch provided on the end face of the incident end of the shaping shielding body;

[0022] The cylindrical notch is located at the central angle of the fan-shaped cylindrical notch;

[0023] The central axis of the cylindrical notch, the central axis of the fan-shaped cylindrical notch, and the axis of the shaping shielding body coincide;

[0024] The diameter of the cylindrical notch is equal to the diameter of the secondary collimating channel and is communicated with the exit opening of the secondary collimating channel;

[0025] The secondary scatterer is located within the cylindrical notch.

[0026] Furthermore, the primary scatterer is a sphere made of aluminum, with a diameter equal to that of the primary collimation channel, and its center of the sphere coincides with the intersection point of the extension lines of the axes of the primary collimation channel and the secondary collimation channel.

[0027] Furthermore, the gamma-ray source is a sphere with a diameter ranging from 0.5 cm to 1 cm, and its center of the sphere is located on the extension line of the axis of the primary collimation channel.

[0028] Furthermore, the gamma-ray source is a cylinder with an outer diameter ranging from 0.5 cm to 1 cm, and its axis is located on the extension line of the axis of the primary collimation channel.

[0029] Furthermore, the secondary scatterer is a sphere made of aluminum, with a diameter equal to that of the secondary collimation channel, and its center of the sphere is located on the central axis of the cylindrical notch;

[0030] The axial heights of the cylindrical notch and the fan-shaped cylindrical notch are equal to the diameter of the secondary scatterer.

[0031] Furthermore, the nuclide type of the gamma-ray source is 137 Cs;

[0032] The diameter ranges of both the primary collimation channel and the secondary collimation channel are from 0.5 cm to 1 cm;

[0033] The outer diameter of the shaping shielding body is equal to the outer diameter of the secondary collimation shielding body.

[0034] A method for generating an adjustable-energy gamma-ray fan beam source, using the above-mentioned adjustable-energy gamma-ray fan beam source generating device, is characterized in that it includes the following steps:

[0035] Step 1: Make the gamma-ray source emit gamma rays towards the primary collimation shielding body;

[0036] Step 2: Collimate the gamma rays using the primary collimation shielding body to form a primary collimated gamma-ray beam;

[0037] Step 3: Make the primary collimated gamma-ray beam undergo Compton scattering with the primary scatterer and then enter the secondary collimation shielding body;

[0038] Step 4: Collimate the primary collimated gamma-ray beam after Compton scattering using the secondary collimation shielding body to form a secondary collimated gamma-ray beam;

[0039] Step 5: Make the secondary collimated gamma-ray beam undergo Compton scattering with the secondary scatterer and then exit from the fan-shaped radiation notch on the incident end face of the shaping shielding body to form a gamma-ray fan beam source;

[0040] Step 6: Drive the gamma-ray source and the first-level collimating shield to rotate simultaneously around the center point of the first-level scatterer, and repeat Steps 3 to 5 to form gamma-ray fan sources with different energies, thus completing the generation of an adjustable-energy gamma-ray fan source.

[0041] Advantages of the present invention:

[0042] 1. The adjustable-energy gamma-ray fan source generation device and method provided by the present invention can realize continuous adjustment of the energy of the gamma-ray source without replacing the radiation source through the settings of the first-level collimating shield, the first-level scatterer, and the second-level collimating shield. At the same time, a fan-shaped radiation notch is provided on the end face of the shaping shield, thereby generating an adjustable-energy gamma-ray fan source. The combination of the two can quickly obtain complete and clear images of different regions of complex objects.

[0043] 2. The adjustable-energy gamma-ray fan source generation device and method provided by the present invention can realize continuous calibration of the detection efficiency of the gamma-ray detector.

[0044] 3. The adjustable-energy gamma-ray fan source generation device and method provided by the present invention can help measure more basic nuclear parameters of the interaction between gamma rays and matter.

[0045] 4. Since the adjustable-energy gamma-ray fan source generation device and method provided by the present invention can generate monoenergetic gamma rays in multiple energy bands, it can be widely applied to the research on the interaction between gamma rays and matter and industrial detection. Description of the Drawings

[0046] Figure 1 is a cross-sectional view of an embodiment of an adjustable-energy gamma-ray fan source generation device of the present invention (the drive mechanism is not shown);

[0047] Figure 2 is a schematic structural principle diagram of the shaping shield generating fan-shaped gamma rays in the embodiment of the present invention.

[0048] Reference Numerals in the Drawings:

[0049] 1 - gamma-ray source, 2 - first-level collimating shield, 3 - first-level scatterer, 4 - second-level collimating shield, 5 - second-level scatterer, 6 - shaping shield, 7 - second-level collimated gamma-ray beam, 10 - first-level collimated gamma-ray beam, 21 - fan-columnar notch. Detailed Embodiments

[0050] The technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0051] An adjustable energy gamma-ray fan-shaped source generating device provided by an embodiment of the present invention, as Figure 1 shown, includes a gamma-ray source 1, a primary collimation shield 2, a primary scatterer 3, a secondary collimation shield 4, a secondary scatterer 5, a shaping shield 6, and also includes a driving mechanism;

[0052] The material of the primary collimation shield 2 is lead, and the whole is cylindrical, with an axial height of 10 cm, an outer diameter of 10 cm, and a cylindrical primary collimation channel passing through both ends thereof; the diameter range of the primary collimation channel is 0.5 cm to 1 cm, and in this embodiment, the diameter of the primary collimation channel is equal to 1 cm, and the axis of the primary collimation channel coincides with the axis of the primary collimation shield 2;

[0053] The nuclide type of the gamma-ray source 1 is 137 Cs, located outside the entrance of the primary collimation channel; the gamma-ray source 1 is a sphere or a cylinder; when the gamma-ray source 1 is a sphere, its diameter range is 0.5 cm to 1 cm, and in this embodiment, its diameter is 1 cm; the center of the sphere of the gamma-ray source 1 is located on the extension line of the axis of the primary collimation channel; when the gamma-ray source 1 is a cylinder, its outer diameter range is 0.5 cm to 1 cm, and its axis is located on the extension line of the axis of the primary collimation channel.

[0054] The material of the secondary collimation shield 4 is lead, and the whole is cylindrical, with an axial height of 40 cm, an outer diameter of 50 cm, and a cylindrical secondary collimation channel passing through both ends thereof; the outer diameter of the secondary collimation shield 4 is greater than the outer diameter of the primary collimation shield 2; the diameter range of the secondary collimation channel is 0.5 cm to 1 cm, and in this embodiment, the diameter of the secondary collimation channel is equal to 1 cm; the axis of the secondary collimation channel coincides with the axis of the secondary collimation shield 4;

[0055] The primary scatterer 3 is located outside the entrance of the secondary collimation channel and corresponds to the exit of the primary collimation channel; the distance from the center of the primary scatterer 3 to the bottom surface of the primary collimation shield 2 is 5 cm; the material of the primary scatterer 3 is aluminum, and the whole is a sphere, and its diameter is equal to the diameter of the primary collimation channel, that is, 1 cm, and the center of its sphere coincides with the intersection point of the extension lines of the axes of the primary collimation channel and the secondary collimation channel.

[0056] As Figure 2As shown, the shaping shield 6 is made of lead and is in the shape of a cylinder with an outer diameter of 50 cm and an axial height of 40 cm. The shaping shield 6 is arranged outside the exit end of the secondary collimating shield 4, and its incident end face is in close contact with the exit end face of the secondary collimating shield 4. A fan-shaped radiation notch for the horizontal emission of gamma rays is provided on the incident end face of the shaping shield 6. The radiation notch is composed of a cylindrical notch and a sector-cylindrical notch 21. The cylindrical notch is located at the central angle of the sector-cylindrical notch 21. The central axis of the cylindrical notch, the central axis of the sector-cylindrical notch 21, and the axis of the shaping shield 6 coincide. The diameter of the cylindrical notch is equal to the diameter of the secondary collimating channel. The cylindrical notch is communicated with the exit of the secondary collimating channel, so that the entrance of the radiation notch is communicated with the exit of the secondary collimating shield 4. The axial height of the cylindrical notch and the sector-cylindrical notch is 1 cm, and the central angle β of the sector-cylindrical notch is 30 degrees.

[0057] The secondary scatterer 5 is located inside the cylindrical notch and also outside the exit of the secondary collimating channel. The secondary scatterer 5 is made of aluminum and is in the shape of a sphere with a diameter of 1 cm. Its center of the sphere is located on the central axis of the cylindrical notch, so that the spherical surface of the secondary scatterer 5 is tangent to the exit end face of the secondary collimating shield 4 and the bottom surface of the radiation notch respectively.

[0058] The above adjustable energy gamma-ray fan beam source generating device is adopted, and the following specific steps are carried out:

[0059] Step 1: Make the gamma-ray source 1 emit gamma rays to the primary collimating shield 2.

[0060] Step 2: Collimate the gamma rays by using the primary collimating shield 2 to form a primary collimated gamma-ray beam 10.

[0061] Step 3: Make the primary collimated gamma-ray beam 10 undergo Compton scattering with the primary scatterer 3 and then enter the secondary collimating shield 4.

[0062] Step 4: Collimate the primary collimated gamma-ray beam 10 after Compton scattering by using the secondary collimating shield 4 to form a secondary collimated gamma-ray beam 7.

[0063] Step 5: Make the secondary collimated gamma-ray beam 7 undergo Compton scattering with the secondary scatterer 5 and then exit from the fan-shaped radiation notch on the incident end face of the shaping shield 6 to form a gamma-ray fan beam source.

[0064] Step 6: Drive the gamma-ray source 1 and the primary collimating shield 2 to rotate simultaneously around the center point of the primary scatterer 3 by a driving mechanism and repeat Steps 3 to 5 to form gamma-ray fan beam sources with different energies, and complete the generation of the adjustable energy gamma-ray fan beam source.

[0065] As described above, it is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims described.

Claims

1. An adjustable energy gamma-ray fan source generating device, characterized in that: It includes a gamma-ray source (1), a primary collimation shield (2), a primary scatterer (3), a secondary collimation shield (4), a secondary scatterer (5), a shaping shield (6) and a driving mechanism; The gamma-ray source (1) is located outside the entrance of the primary collimation shield (2) and is used to emit gamma rays; The primary scatterer (3) is located between the exit of the primary collimation shield (2) and the entrance of the secondary collimation shield (4); The shaping shield (6) is arranged outside the exit end of the secondary collimation shield (4), and its entrance end face is in close contact with the exit end face of the secondary collimation shield (4). A fan-shaped radiation notch for the emission of gamma rays is provided on the entrance end face thereof; the entrance of the radiation notch is communicated with the exit of the secondary collimation shield (4); The secondary scatterer (5) is located inside the entrance of the radiation notch and corresponds to the exit of the secondary collimation shield (4); The driving end of the driving mechanism is respectively connected to the gamma-ray source (1) and the primary collimation shield (2), and is used to drive the gamma-ray source (1) and the primary collimation shield (2) to rotate simultaneously around the center point of the primary scatterer (3), so as to change the energy of the gamma rays emitted from the radiation notch.

2. The adjustable energy gamma-ray fan source generating device according to claim 1, characterized in that: The primary collimation shield (2) is cylindrical, made of lead, and is internally provided with a cylindrical primary collimation channel penetrating through both ends thereof; The axis of the primary collimation channel coincides with the axis of the primary collimation shield (2), and its exit is corresponding to the primary scatterer (3); The gamma-ray source (1) is located outside the entrance of the primary collimation channel.

3. The adjustable energy gamma-ray fan source generating device according to claim 2, characterized in that: The secondary collimation shield (4) is cylindrical, made of lead, and is internally provided with a cylindrical secondary collimation channel penetrating through both ends thereof; The outer diameter of the secondary collimation shield (4) is larger than the outer diameter of the primary collimation shield (2); The axis of the secondary collimation channel coincides with the axis of the secondary collimation shield (4); The primary scatterer (3) is located outside the entrance of the secondary collimation channel.

4. The adjustable energy gamma-ray fan source generating device according to claim 3, characterized in that: The shaping shield (6) is cylindrical and made of lead; The radiation notch includes a cylindrical notch and a fan-columnar notch (21) provided on the entrance end face of the shaping shield (6); The cylindrical notch is located at the central angle of the fan-columnar notch (21); The central axis of the cylindrical notch, the central axis of the fan-columnar notch (21) and the axis of the shaping shield (6) coincide; The diameter of the cylindrical notch is equal to the diameter of the secondary collimation channel and is communicated with the exit of the secondary collimation channel; The secondary scatterer (5) is located inside the cylindrical notch.

5. The adjustable energy gamma-ray fan source generating device according to claim 4, characterized in that: The first-level scatterer (3) is a sphere made of aluminum, with a diameter equal to that of the first-level collimation channel, and its center of the sphere coincides with the intersection point of the extension lines of the axes of the first-level collimation channel and the second-level collimation channel.

6. The adjustable energy gamma-ray fan-shaped source generating device according to claim 5, wherein: The gamma-ray source (1) is a sphere with a diameter ranging from 0.5 cm to 1 cm, and its center of the sphere is located on the extension line of the axis of the first-level collimation channel.

7. The adjustable energy gamma-ray fan-shaped source generating device according to claim 5, wherein: The gamma-ray source (1) is a cylinder with an outer diameter ranging from 0.5 cm to 1 cm, and its axis is located on the extension line of the axis of the first-level collimation channel.

8. The adjustable energy gamma-ray fan-shaped source generating device according to claim 6 or 7, wherein: The second-level scatterer (5) is a sphere made of aluminum, with a diameter equal to that of the second-level collimation channel, and its center of the sphere is located on the central axis of the cylindrical notch; The axial heights of the cylindrical notch and the fan-shaped cylindrical notch (21) are equal to the diameter of the second-level scatterer (5).

9. The adjustable energy gamma-ray fan-shaped source generating device according to claim 8, wherein: The nuclide type of the gamma-ray source (1) is 137 Cs; The diameters of both the first-level collimation channel and the second-level collimation channel range from 0.5 cm to 1 cm; The outer diameter of the shaping shielding body (6) is equal to the outer diameter of the second-level collimation shielding body (4).

10. A method for generating an adjustable-energy gamma-ray fan beam source, which uses the adjustable-energy gamma-ray fan beam source generating device according to any one of claims 1-9, characterized in that, It includes the following steps: Step 1: Make the gamma-ray source (1) emit gamma rays towards the first-level collimation shielding body (2); Step 2: Use the first-level collimation shielding body (2) to collimate the gamma rays to form a first-level collimated gamma-ray beam (10); Step 3: Make the first-level collimated gamma-ray beam (10) undergo Compton scattering with the first-level scatterer (3) and then enter the second-level collimation shielding body (4); Step 4: Use the second-level collimation shielding body (4) to collimate the first-level collimated gamma-ray beam (10) after Compton scattering to form a second-level collimated gamma-ray beam (7); Step 5: Make the second-level collimated gamma-ray beam (7) undergo Compton scattering with the second-level scatterer (5) and then exit from the fan-shaped radiation notch on the incident end face of the shaping shielding body (6) to form a gamma-ray fan-shaped source; Step 6: Drive the gamma-ray source (1) and the first-level collimation shielding body (2) to rotate simultaneously around the center point of the first-level scatterer (3) through a driving mechanism and repeat Steps 3 to 5 to form gamma-ray fan-shaped sources with different energies, thus completing the generation of the adjustable energy gamma-ray fan-shaped source.

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