CN212434270U - Novel portable gamma irradiation collimator - Google Patents
Novel portable gamma irradiation collimator Download PDFInfo
- Publication number
- CN212434270U CN212434270U CN202021109282.6U CN202021109282U CN212434270U CN 212434270 U CN212434270 U CN 212434270U CN 202021109282 U CN202021109282 U CN 202021109282U CN 212434270 U CN212434270 U CN 212434270U
- Authority
- CN
- China
- Prior art keywords
- irradiation
- opening
- gamma
- collimator
- equal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Radiation-Therapy Devices (AREA)
Abstract
The utility model discloses a novel portable gamma irradiation collimator. The novel portable gamma irradiation collimator comprises: an irradiation source chamber, a shield and an irradiation opening; the irradiation source chamber is used for accommodating gamma irradiation sources with different sizes; the irradiation opening is used for collimating and emitting gamma rays emitted by the gamma irradiation source; the irradiation source cavity is positioned in the central position of the shielding body; the irradiation opening penetrates through the shielding body and is communicated with the irradiation source cavity; the uniformity and the scattering property of the gamma rays emitted from the irradiation opening meet preset requirements. The novel portable gamma irradiation collimator can accommodate gamma irradiation sources with different sizes, the uniformity and the scattering characteristic of a generated gamma radiation field meet preset requirements, and the application range of the portable gamma irradiation collimator is expanded.
Description
Technical Field
The embodiment of the utility model provides a relate to ionizing radiation dosimetry field, especially relate to a novel portable gamma irradiation collimator.
Background
After the gamma radiation collimator is installed with gamma radioactive source, it can provide gamma radiation field meeting certain technical index, and is commonly used for food sterilization, industrial flaw detection and ionizing radiation dosimetry research. At present, most gamma irradiation collimators are heavy, and are fixed in a gamma irradiation laboratory in order to ensure that an emergent gamma radiation field meets certain technical requirements. With the development of ionizing radiation technology and its application, in some special irradiation requirements, it cannot be performed in a gamma irradiation laboratory, and needs to be operated on site or on line, so that it is necessary to develop and design a portable gamma irradiation collimator.
In the existing portable gamma irradiation collimator, a gamma radioactive source is placed at one side of an irradiation opening close to the center of a shielding body, and only a specific gamma radioactive source can be placed, and gamma radioactive sources with different sizes correspond to different gamma irradiation collimators, so that only one gamma radioactive source with one size can be placed for the designed gamma irradiation collimator, the application range is narrow, and the applicability is low; in addition, the aperture of the opening of the irradiation opening of the existing portable gamma irradiation collimator, which is far away from the center of the shielding body, is larger, and the size of the radiation attenuation sheet matched with the irradiation opening is larger, so that the irradiation collimator is inconvenient to use under the condition of having requirements on the size, the application scene of the gamma irradiation collimator is limited, and the application range of the portable gamma irradiation collimator is further influenced. Because all the size parameters in the gamma irradiation collimator are organically combined, the portable gamma irradiation collimator which meets the requirements of the uniformity and the scattering property of the radiation field can be designed, so the size of the chamber for placing the gamma radioactive source and the caliber of the opening of the irradiation opening which deviates from the center of the shielding body cannot be randomly adjusted, otherwise, the portable gamma irradiation collimator cannot meet the requirements of the uniformity and the scattering property of the radiation field.
SUMMERY OF THE UTILITY MODEL
The utility model provides a novel portable gamma irradiation collimator to enlarge portable gamma irradiation collimator's application scope, improve its suitability.
The embodiment of the utility model provides a novel portable gamma irradiation collimator, this novel portable gamma irradiation collimator includes: an irradiation source chamber, a shield and an irradiation opening; the irradiation source chamber is used for accommodating gamma irradiation sources with different sizes; the irradiation opening is used for collimating and emitting gamma rays emitted by the gamma irradiation source;
the irradiation source cavity is positioned in the central position of the shielding body; the irradiation opening penetrates through the shielding body and is communicated with the irradiation source cavity;
the uniformity and the scattering property of the gamma rays emitted from the irradiation opening meet preset requirements.
Optionally, a side of the irradiation opening facing away from the irradiation source chamber is a first opening, a surface of a joint of the shield and the first opening is a first surface, and the first surface is parallel to the first opening.
Optionally, the irradiation source chamber is cylindrical; the bottom surface of the cylinder is parallel to the central axis of the irradiation opening; the first surface and the irradiation source chamber are both symmetrically distributed along a central axis of the irradiation opening.
Optionally, the height H of the sidewall of the irradiation source chamber communicating with the irradiation opening satisfies: h is more than or equal to 10mm and less than or equal to 30 mm; the diameter D of the bottom surface of the irradiation source cavity satisfies the following condition: d is more than or equal to 8mm and less than or equal to 20 mm.
Optionally, the shield further comprises a second surface; the second surface is connected with the first surface; the second surface is spherical; the center of the sphere coincides with the center of the irradiation source cavity; the radius R of the sphere satisfies: r is more than or equal to 35 mm.
Optionally, one side of the irradiation opening close to the irradiation source chamber is a second opening, and a height W of the second opening satisfies: w is more than or equal to 8mm and less than or equal to 20 mm.
Optionally, an included angle θ between the sidewall of the irradiation opening and the central axis of the irradiation opening satisfies: theta is more than or equal to 20 degrees and less than or equal to 45 degrees.
Optionally, in a direction parallel to a central axis of the irradiation opening, a distance L between the first opening and the second opening satisfies: l is more than or equal to 10mm and less than or equal to 35 mm.
Optionally, the material of the shielding body includes lead and its alloy, tungsten and its alloy or depleted uranium and its alloy.
The embodiment of the utility model provides a novel portable gamma irradiation collimator puts the gamma irradiation source that sets up the irradiation source cavity in order to hold different sizes through the central point at the shielding body, sets up the irradiation opening that runs through the shielding body and communicate with the irradiation source cavity to the gamma ray of collimation outgoing gamma irradiation source transmission, thereby realize the collimation in gamma radiation field. The homogeneity and the scattering characteristic of the gamma-ray of irradiation opening outgoing satisfy and predetermine the requirement, and the homogeneity and the scattering characteristic of the gamma radiation field after the collimation satisfy and predetermine the requirement promptly, to sum up, one the embodiment of the utility model provides a novel portable gamma irradiation collimator can be applicable to the gamma irradiation source of not unidimensional, and the opening bore that deviates from shield center one side can reduce as required to the homogeneity and the scattering characteristic of the gamma radiation field of production satisfy and predetermine the requirement, consequently, can enlarge the application scope of portable gamma irradiation collimator, improve its suitability.
Drawings
Fig. 1 is a schematic structural diagram of a novel portable gamma irradiation collimator provided by an embodiment of the present invention;
fig. 2 is a schematic structural diagram of a radiation attenuation sheet configured with the novel portable gamma radiation collimator shown in fig. 1 according to an embodiment of the present invention;
fig. 3 is a schematic diagram of the uniformity of a gamma radiation field formed by a novel portable gamma radiation collimator provided by an embodiment of the present invention;
fig. 4 is a schematic diagram of the scattering characteristic of the gamma radiation field formed by the novel portable gamma radiation collimator according to the embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.
Fig. 1 is a schematic structural diagram of a novel portable gamma irradiation collimator provided by an embodiment of the present invention. As shown in fig. 1, the novel portable gamma irradiation collimator 100 includes: the irradiation source chamber 110, the shield 120, and the irradiation opening 130; the irradiation source chamber 110 is used for accommodating gamma irradiation sources with different sizes; the irradiation opening 130 is used to emit gamma rays emitted from a gamma irradiation source.
The irradiation source chamber 110 is located in the center of the shield 120; an irradiation opening 130 extends through the shield 120 and communicates with the irradiation source chamber 110.
The uniformity and scattering characteristics of the gamma rays emitted from the irradiation openings 130 satisfy preset requirements.
Specifically, as shown in fig. 1, an irradiation source chamber 110 is disposed at a central position of a shield 120, a surface of the irradiation source chamber 110 is surrounded by inner surfaces of the shield 120, γ irradiation sources of different sizes can be accommodated in the irradiation source chamber 110, the γ irradiation sources provide a radiation field in a direction of 4 pi, that is, the γ irradiation sources can emit γ rays in various directions; the irradiation opening 130 penetrates through the shield 120 and is communicated with the irradiation source chamber 110, that is, the irradiation opening 130 is communicated with the irradiation source chamber 110 and the external environment, only part of the gamma rays emitted by the gamma irradiation source is emitted to the external environment through the irradiation opening 130, and the rest is absorbed by the shield 120, so that the emission angle of the gamma rays is within a certain angle range, and therefore, the novel portable gamma irradiation collimator 100 restricts the radiation field in the direction of 4 pi into a quasi-straight radiation field. The shield 120 may be made of radiation shielding materials such as lead and its alloy, tungsten and its alloy, and depleted uranium.
The uniformity and scattering characteristics of the collimated gamma rays emitted from the irradiation opening 130 satisfy preset requirements, that is, the uniformity and scattering characteristics of the collimated gamma radiation field satisfy preset requirements, for example: the uniformity of the collimated gamma radiation field meets the requirement that the diameter of a uniform field is not less than 30cm at a position 100cm away from the center of the novel portable gamma radiation collimator 100, and the relative deviation of the air kerma rate in the uniform field is not more than 5%; the scattering characteristic of the collimated gamma radiation field meets the condition that on the central axis of the radiation opening 130, the air kerma rate is in direct proportion to the reciprocal of the square of the distance from the center of the gamma radiation source to the center of the detector, and the deviation from the ideal value is not more than 5%. It should be noted that the embodiments of the present invention merely illustrate the preset requirements for uniformity and scattering characteristics of the collimated γ -radiation field, and do not limit the present invention.
The embodiment of the utility model provides a novel portable gamma irradiation collimator puts the gamma irradiation source that sets up the irradiation source cavity in order to hold different sizes through the central point at the shielding body, sets up the irradiation opening that runs through the shielding body and communicate with the irradiation source cavity to the gamma ray of collimation outgoing gamma irradiation source transmission, thereby realize the collimation in gamma radiation field. The homogeneity and the scattering characteristic of the gamma-ray of irradiation opening outgoing satisfy and predetermine the requirement, and the homogeneity and the scattering characteristic of the gamma radiation field after the collimation satisfy and predetermine the requirement promptly, to sum up, one the embodiment of the utility model provides a novel portable gamma irradiation collimator can be applicable to the gamma irradiation source of not unidimensional, and the opening bore that deviates from shield center one side can reduce as required to the homogeneity and the scattering characteristic of the gamma radiation field of production satisfy and predetermine the requirement, consequently, can enlarge the application scope of portable gamma irradiation collimator, improve its suitability.
Optionally, with continued reference to fig. 1, a side of the irradiation opening 130 facing away from the irradiation source chamber 110 is a first opening 131, a surface of a junction of the shield 120 and the first opening 131 is a first surface 121, and the first surface 121 is parallel to the first opening 131.
Specifically, as shown in fig. 1, the first surface 121 is parallel to the first opening 131, the distance between the first opening 131 and the second opening 132 is L, the included angle between the sidewall of the irradiation opening 130 and the central axis of the irradiation opening 130 is θ, and geometrically, the distance L between the first opening 131 and the second opening 132 is not related to the included angle θ between the sidewall of the irradiation opening 130 and the central axis of the irradiation opening 130, so that two parameters are only limited by the uniformity and scattering characteristics of the γ rays emitted from the irradiation opening 130 to meet the preset requirements, the degree of relation between the distance L between the first opening 131 and the second opening 132 and the included angle θ between the sidewall of the irradiation opening 130 and the central axis of the irradiation opening 130 is reduced, and it is beneficial to more flexibly set the included angle θ between the sidewall of the first opening 131 and the second opening 132 and the central axis of the irradiation opening 130, therefore, the design of the novel portable gamma irradiation collimator with the lower height of the first opening 131 is facilitated, and the size of the radiation attenuation sheet matched with the novel portable gamma irradiation collimator is reduced, so that the use scenes of the novel portable gamma irradiation collimator are increased, and the application range of the novel portable gamma irradiation collimator is further improved. It should be noted that, in practical applications, the first surface 121 and the first opening 131 may be in an approximately parallel relationship.
Optionally, with continued reference to fig. 1, the irradiation source chamber 110 is cylindrical; the bottom surface of the cylindrical shape is parallel to the central axis of the irradiation opening 130; the first surface 121 and the irradiation source chamber 110 are symmetrically distributed along the central axis of the irradiation opening 130.
Specifically, as shown in fig. 1, the bottom surface of the cylinder is parallel to the central axis (the dotted arrow shown in the figure) of the irradiation opening 130, and in practical application, a common exemption-level gamma irradiation source or a V-type gamma irradiation source is mainly cylindrical, so that the irradiation source chamber 110 accommodating gamma irradiation sources of different sizes is also set to be cylindrical, and the occupation of too much space is avoided while the common exemption-level gamma irradiation source or V-type gamma irradiation source on the market can be accommodated.
Optionally, with continued reference to fig. 1, the height H of the sidewall of the irradiation source chamber 110 in communication with the irradiation opening 130 satisfies: h is more than or equal to 10mm and less than or equal to 30 mm; the diameter D of the bottom surface of the irradiation source chamber 110 satisfies: d is more than or equal to 8mm and less than or equal to 20 mm.
Specifically, the height of the existing gamma irradiation source is generally not more than 10mm, the diameter of the bottom surface of the gamma irradiation source is generally not more than 8mm, and in order to easily take and place the gamma irradiation source, the size of the irradiation source chamber 110 needs to be set to be greater than or equal to the size of the gamma irradiation source, so the height H of the side wall of the irradiation source chamber 110, which is communicated with the irradiation opening 130, is greater than or equal to 10mm, and the diameter D of the bottom surface of the irradiation source chamber 110 is greater than or equal to 8 mm. In addition, if the height H of the side wall of the irradiation source chamber 110 communicated with the irradiation opening 130 and the diameter D of the bottom surface of the irradiation source chamber 110 are too large, the uniformity and scattering characteristics of the emergent gamma radiation field and the shielding effect in the non-collimation direction are affected, monte carlo simulation results show that the height H of the side wall of the irradiation source chamber 110 communicated with the irradiation opening 130 is not more than 30mm, and the diameter D of the bottom surface of the irradiation source chamber 120 is not more than 20mm, so that the height H of the side wall of the irradiation source chamber 110 communicated with the irradiation opening 130 is 10mm or more than H or less than 30 mm; the diameter D of the bottom surface of the irradiation source chamber 110 is more than or equal to 8mm and less than or equal to 20 mm.
Optionally, with continued reference to fig. 1, the shield 120 further includes a second surface 122; the second surface 122 is connected with the first surface 121; the second surface 122 is spherical; and the center of the sphere coincides with the center of the irradiation source chamber 110; the radius R of the sphere satisfies: r is more than or equal to 35 mm.
Specifically, the shielding rate of the novel portable gamma irradiation collimator 100 for gamma rays radiated by the gamma radiation source in the main shielding direction is not less than 99.9% to ensure the radiation safety of surrounding personnel, and the shielding body 120 is combined for137The gamma ray shielding capability of Cs, the radius R of the sphere in which the second surface 122 of the shield 120 is located satisfies: r is more than or equal to 35 mm. For example, the gamma radiation source is137The Cs radiation source and the shield 120 are made of tungsten alloy, and are combined with tungsten alloy pairs137The shielding capability of the gamma rays of the Cs and the thickness of the main shielding direction at least reach 38mm can realize the alignment of the novel portable gamma irradiation collimator 100 in the main shielding direction137The shielding rate of the gamma rays of Cs is not less than 99.9%, and considering that the irradiation source chamber 110 is disposed at the center of the shield 120, the radius R of the sphere where the second surface 132 is located should be greater than or equal to 50 mm. In practical applications, the radius R of the sphere where the second surface 122 is located is flexibly set according to the type of the gamma radiation source and the material of the shield 120.
Optionally, with continued reference to fig. 1, a side of the irradiation opening 130 close to the irradiation source chamber 110 is a second opening 132, and a height W of the second opening 132 satisfies: w is more than or equal to 8mm and less than or equal to 20 mm.
Specifically, the novel portable gamma irradiation collimator 100 is capable of forming a gamma irradiation field having uniformity and scattering characteristics satisfying predetermined requirements. For example, the uniformity meets the preset requirement, the diameter of a uniform field 100cm away from the center of the novel portable gamma irradiation collimator 100 is not less than 30cm, and the relative deviation of the air kerma rate in the uniform field is not more than 5%; the scattering property meets the preset requirement, which means that on the central axis of the radiation opening 130, the air kerma rate is in direct proportion to the reciprocal of the square of the distance from the center of the gamma radiation source to the center of the detector, and the deviation from the ideal value is not more than 5%. The height H of the side wall where the irradiation source chamber 110 communicates with the irradiation opening 130 satisfies: h is more than or equal to 10mm and less than or equal to 30mm, and the diameter D of the bottom surface of the irradiation source chamber 110 satisfies the following condition: d is more than or equal to 8mm and less than or equal to 20mm, and the radius R of the sphere where the second surface 122 of the shielding body 120 is located satisfies: when R is larger than or equal to 35mm, the height W of the second opening 132 is set to be larger than or equal to 8mm and smaller than or equal to 20mm, so that the uniformity and the scattering property of the gamma radiation field formed by the novel portable gamma irradiation collimator 100 can meet the preset requirements.
Optionally, with continued reference to fig. 1, the included angle θ between the sidewall of the irradiation opening 130 and the central axis of the irradiation opening 130 satisfies: theta is more than or equal to 20 degrees and less than or equal to 45 degrees.
Specifically, the height H of the sidewall where the irradiation source chamber 110 communicates with the irradiation opening 130 satisfies: h is more than or equal to 10mm and less than or equal to 30mm, and the diameter D of the bottom surface of the irradiation source chamber 110 satisfies the following condition: d is more than or equal to 8mm and less than or equal to 20mm, and the radius R of the sphere where the second surface 122 of the shielding body 120 is located satisfies: when the R is larger than or equal to 35mm, the angle θ between the side wall of the irradiation opening 130 and the central axis of the irradiation opening 130 is set to be not less than 20 degrees and not more than 45 degrees, so that the uniformity and the scattering property of the gamma radiation field formed by the novel portable gamma irradiation collimator 100 can be ensured to meet the preset requirements.
Alternatively, with continued reference to fig. 1, the distance L between the first opening 131 and the second opening 132 in a direction parallel to the central axis of the irradiation opening 130 satisfies: l is more than or equal to 10mm and less than or equal to 35 mm.
Specifically, the height H of the sidewall where the irradiation source chamber 110 communicates with the irradiation opening 130 satisfies: h is more than or equal to 10mm and less than or equal to 30mm, and the diameter D of the bottom surface of the irradiation source chamber 110 satisfies the following condition: d is more than or equal to 8mm and less than or equal to 20mm, and the radius R of the sphere where the second surface 122 of the shielding body 120 is located satisfies: when R is greater than or equal to 35mm, the distance L between the first opening 131 and the second opening 132 along the direction parallel to the central axis of the irradiation opening 130 is set to be greater than or equal to 10mm and less than or equal to 35mm, so as to ensure that the gamma radiation field formed by the novel portable gamma irradiation collimator 100 satisfies the above-mentioned predetermined requirements with respect to uniformity and scattering characteristics.
Optionally, with continued reference to fig. 1, the shield 120 is provided with a third surface 123, the third surface 123 being perpendicular to the second surface 122. Specifically, as shown in fig. 1, the third surface 123 is a plane, which provides a flat supporting surface for the novel portable gamma irradiation collimator 100, and improves stability.
In practical application, a radiation attenuation sheet is used in cooperation with the novel portable gamma irradiation collimator 100, and fig. 2 is a schematic structural diagram of the radiation attenuation sheet provided in the embodiment of the present invention in cooperation with the novel portable gamma irradiation collimator shown in fig. 1. As shown in fig. 2, the radiation attenuation sheet 200 includes opposing first and second surfaces 210 and 220, the first surface 210 being a circular plane, the first surface 210 having a diameter/; the second surface 220 comprises an edge area 221 and a middle area 222, wherein the edge area 221 is a circular plane, the middle area 222 is an arc surface, the radius of a spherical surface where the arc surface is located is o, the vertical projection of the middle area 222 on the first surface 210 is a circle, and the diameter of the vertical projection is m; the thickness of the middle region 222 is n, and the thickness of the middle region 222 gradually decreases from the center of the middle region 222 to the edge of the middle region 222.
Specifically, as shown in fig. 2, the arc radius of the middle region 222 is o, and the arc radius o determines the thickness reduction speed, and the smaller the arc radius o, the faster the thickness reduction speed, and the larger the arc radius o, the slower the thickness reduction speed. When the cambered surface radius o takes an appropriate value, the radiation field has the best uniformity. The parameters of the radiation attenuation sheets 200 associated with different novel portable gamma irradiation collimators 100 are selected differently. It should be noted that the uniformity and scattering characteristics of the gamma radiation field attenuated by the radiation attenuation sheet 200 also need to meet the preset requirements.
Illustratively, the gamma radiation source is137The Cs radiation source, the shielding body 120 is made of tungsten alloy, the radius R of the sphere where the second surface 122 of the shielding body 120 is located is 50mm, the height H of the side wall of the radiation source chamber 110 communicated with the radiation opening 130 is 20mm, and the diameter D of the bottom surface of the radiation source chamber 120 is 12 mm. According to the fact that the uniformity and the scattering characteristics of the gamma radiation field formed by the novel portable gamma radiation collimator 100 meet preset requirements, the height W of the second opening 132 is determined to be 12mm, and the side wall of the irradiation opening 130 and the irradiation opening are determinedThe central axis of the radiation opening 130 has an angle theta of 24.23 deg., and the distance L between the first opening 131 and the second opening 132 in a direction parallel to the central axis of the radiation opening 130 is 29 mm.
Fig. 3 is a schematic diagram of uniformity of a gamma radiation field formed by a novel portable gamma radiation collimator according to an embodiment of the present invention. The size parameters are used as the size parameters of the novel portable gamma irradiation collimator, the distance of 100cm from the center of the novel portable gamma irradiation collimator is used as a starting point, the gamma radiation measuring instrument moves towards the horizontal direction and the vertical direction perpendicular to the axis respectively, the attenuation change of the measured air kerma rate relative to the starting point is shown in figure 3, the intensity change of a radiation field is not more than 4% within the range of 15cm from the central axis of the central axis, and therefore, the uniformity of the gamma radiation field formed by the novel portable gamma irradiation collimator corresponding to the size parameters meets the preset requirement.
Fig. 4 is a schematic diagram of the scattering characteristic of the gamma radiation field formed by the novel portable gamma radiation collimator according to the embodiment of the present invention. The size parameters are used as the size parameters of the novel portable gamma irradiation collimator, the gamma radiation measuring instrument moves within the range of 0.75m to 3m along the central axis of the radiation opening, the variation relation between the measured air specific release kinetic energy rate and the distance square inverse is shown in figure 4, the air specific release kinetic energy rate and the distance square inverse from the gamma radiation source to the center of the detector meet the proportional relation, the deviation of an actual measurement value relative to a fitting straight line is not more than 2%, and therefore the scattering characteristics of a gamma radiation field formed by the novel portable gamma irradiation collimator corresponding to the size parameters meet preset requirements.
Taking the size parameters as the size parameters of the novel portable gamma irradiation collimator, taking the uniformity and scattering characteristics of the gamma radiation field attenuated by the radiation attenuation sheet as the criterion, and obtaining the size parameters of the radiation attenuation sheet through Monte Carlo simulation calculation, as shown in table 1, wherein different size parameters in table 1 correspond to different radiation attenuation sheets.
TABLE 1 values of dimensional parameters of radiation attenuators
| Radiation attenuation sheet | l(mm) | m(mm) | n(mm) | o(mm) |
| 1 | 50 | 40 | 4.50 | 109.03 |
| 2 | 50 | 40 | 9.00 | 106.21 |
| 3 | 50 | 40 | 13.50 | 104.59 |
Compared with the prior art, the embodiment of the utility model provides a radius of the first surface of radiation attenuation piece has reduced nearly 50%, because the radiation attenuation piece uses with novel portable gamma irradiation collimator is supporting, has consequently improved the portability and the suitability of novel portable gamma irradiation collimator to a certain extent.
The gamma radiation measuring instrument respectively moves towards the horizontal direction and the vertical direction which are vertical to the axis by taking the central axis of the radiation attenuation sheet as a starting point, the intensity of a radiation field does not exceed 3% within the range of 15cm from the central axis, and the uniformity of the gamma radiation field formed by the attenuation of the radiation attenuation sheet meets the preset requirement. Along the central axis of the radiation attenuation sheet, the gamma radiation measuring instrument moves in the range of 0.75m to 3m, the air specific kinetic energy rate and the reciprocal of the square of the distance from the gamma radiation source to the center of the detector meet the proportional relation, the deviation of an actual measurement value to a fitting straight line is not more than 3%, and the scattering characteristic of a gamma radiation field formed by attenuation of the radiation attenuation sheet meets the preset requirement.
It should be noted that the foregoing is only a preferred embodiment of the present invention and the technical principles applied. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail with reference to the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the scope of the present invention.
Claims (9)
1. A novel portable gamma irradiation collimator, comprising: an irradiation source chamber, a shield and an irradiation opening; the irradiation source chamber is used for accommodating gamma irradiation sources with different sizes; the irradiation opening is used for collimating and emitting gamma rays emitted by the gamma irradiation source;
the irradiation source cavity is positioned in the central position of the shielding body; the irradiation opening penetrates through the shielding body and is communicated with the irradiation source cavity;
the uniformity and the scattering property of the gamma rays emitted from the irradiation opening meet preset requirements.
2. The novel portable gamma irradiation collimator set forth in claim 1, wherein the side of the irradiation opening facing away from the irradiation source chamber is a first opening, and the surface of the junction of the shield and the first opening is a first surface parallel to the first opening.
3. The novel portable gamma irradiation collimator of claim 2, wherein the irradiation source chamber is cylindrical; the bottom surface of the cylinder is parallel to the central axis of the irradiation opening; the first surface and the irradiation source chamber are both symmetrically distributed along a central axis of the irradiation opening.
4. The novel portable gamma irradiation collimator of claim 3, wherein the height H of the side wall of the irradiation source chamber communicating with the irradiation opening satisfies: h is more than or equal to 10mm and less than or equal to 30 mm; the diameter D of the bottom surface of the irradiation source cavity satisfies the following condition: d is more than or equal to 8mm and less than or equal to 20 mm.
5. The novel portable gamma irradiation collimator of claim 4, wherein said shield further comprises a second surface; the second surface is connected with the first surface; the second surface is spherical; the center of the sphere coincides with the center of the irradiation source cavity; the radius R of the sphere satisfies: r is more than or equal to 35 mm.
6. The novel portable gamma irradiation collimator set forth in claim 5, wherein the irradiation opening is a second opening on a side near the irradiation source chamber, and the height W of the second opening satisfies: w is more than or equal to 8mm and less than or equal to 20 mm.
7. The novel portable gamma irradiation collimator set forth in claim 5, wherein the angle θ between the side wall of the irradiation opening and the central axis of the irradiation opening satisfies: theta is more than or equal to 20 degrees and less than or equal to 45 degrees.
8. The novel portable gamma irradiation collimator of claim 6, wherein a distance L between the first opening and the second opening in a direction parallel to a central axis of the irradiation opening satisfies: l is more than or equal to 10mm and less than or equal to 35 mm.
9. The novel portable gamma irradiation collimator of claim 1, wherein the shielding material comprises lead and its alloys, tungsten and its alloys or depleted uranium and its alloys.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021109282.6U CN212434270U (en) | 2020-06-16 | 2020-06-16 | Novel portable gamma irradiation collimator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021109282.6U CN212434270U (en) | 2020-06-16 | 2020-06-16 | Novel portable gamma irradiation collimator |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN212434270U true CN212434270U (en) | 2021-01-29 |
Family
ID=74280884
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202021109282.6U Active CN212434270U (en) | 2020-06-16 | 2020-06-16 | Novel portable gamma irradiation collimator |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN212434270U (en) |
-
2020
- 2020-06-16 CN CN202021109282.6U patent/CN212434270U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Li et al. | Evaluation of the ArcCHECK QA system for IMRT and VMAT verification | |
| US10441815B2 (en) | Neutron capture therapy system and gamma ray detector for neutron capture therapy | |
| US10500419B2 (en) | Radiation shields for LINAC head and system | |
| Wochnik et al. | Out-of-field doses for scanning proton radiotherapy of shallowly located paediatric tumours—a comparison of range shifter and 3D printed compensator | |
| US20170108591A1 (en) | Gamma-ray measurement device and gamma-ray measurement method | |
| CN212434270U (en) | Novel portable gamma irradiation collimator | |
| US11458336B2 (en) | Neutron capture therapy system comprising a beam shaping assembly configured to shape a neutron beam | |
| Daartz et al. | Characterization of a mini‐multileaf collimator in a proton beamline | |
| JP6613464B2 (en) | Neutron beam detector | |
| Lárraga-Gutiérrez | Experimental determination of field factors () for small radiotherapy beams using the daisy chain correction method | |
| CN105223625A (en) | Beam guiding device and comprise the radiation examination device of this beam guiding device | |
| CN111681801A (en) | Novel portable gamma irradiation collimator and design method thereof | |
| WO2015107727A1 (en) | Neutron radiation detector and neutron capture therapy apparatus | |
| Olofsson et al. | A widely tested model for head scatter influence on photon beam output | |
| CN211478662U (en) | Gamma dosimeter field calibration system based on X-ray source | |
| Ashokkumar et al. | Comparison of head scatter factor for 6MV and 10MV flattened (FB) and unflattened (FFF) photon beam using indigenously designed columnar mini phantom | |
| JP6053122B2 (en) | Neutron radiography equipment | |
| Dawod et al. | Dose validation of physical wedged asymmetric fields in artiste linear accelerator | |
| Sahoo et al. | Monte Carlo modeling of 60Co HDR brachytherapy source in water and in different solid water phantom materials | |
| Warrener et al. | Small field in‐air output factors: the role of miniphantom design and dosimeter type | |
| Kim et al. | The equivalent square concept for the head scatter factor based on scatter from flattening filter | |
| Jomehzadeh et al. | Effect of material and wall thickness buildup caps on the head scatter factor measurements in irregular fields shielded by cerrobend | |
| Dwivedi et al. | Dosimetry of a 6 MV flattening filter-free small photon beam using various detectors | |
| Sander et al. | The NPL air kerma primary standard TH100C for high dose rate 192Ir brachytherapy sources. | |
| IL276068B1 (en) | Iort device for radiotherapy treatment of cancer patients |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |