A device for adjusting a beam field of irradiation

Abstract

This utility model relates to the field of radiotherapy technology, and in particular to a device for adjusting the beam irradiation field. The device includes: a support assembly with a base rail, a first support base, and a second support base; a circular collimator mounted on the first support base; and a square collimator mounted on the second support base. The support assembly further includes a seat plate slidably connected to the base rail, and the first and second support bases are fixed to the top surface of the seat plate. In this utility model, by mounting the circular and square collimators together on the base rail via the seat plate, the size and specifications of the beam irradiation field can be easily selected, simulating the beam environment during radiotherapy, thereby obtaining a calibration factor for the absorbed dose of water in the ionization chamber for radiotherapy, and realizing absolute dose measurement of the radiotherapy equipment.

Description

Technical Field

[0001] This utility model relates to the field of radiotherapy technology, and in particular to a device for adjusting the beam irradiation field. Background Technology

[0002] According to a 2024 research report released by the International Agency for Research on Cancer (IARC) of the World Health Organization, the global incidence of cancer has continued to rise in recent years, and cancer has become an increasingly prominent cause of death. my country has become a major cancer-affected country, both in terms of the number of new cases and deaths. Currently, in addition to conventional treatments, proton and heavy ion therapy has become one of the important methods for treating cancer.

[0003] Accurate measurement of the treatment beam dose is essential in radiotherapy and is fundamental to the treatment process. Currently, the international and domestic practice, based on the recommendations of IAEA Technical Report 398 and AAPM Report TG51, is to first install the ionization chamber detector used for measuring proton and heavy ion beam doses in… 60 Co-γ ray air kerma energy standard device obtained 60 The calibration factor for the Co-γ ray air kerma or water absorbed dose is obtained, and then the calibration factor for the absorbed dose under the proton / heavy ion beam is obtained by following the method recommended in IAEA Technical Report 398 or AAPM Report TG51. Finally, the accurate dose value of the proton / heavy ion beam is obtained by measurement.

[0004] Currently, there are many types of ionization chambers for radiotherapy on the market, including finger-shaped ionization chambers, flat plate ionization chambers, spherical ionization chambers, well-shaped ionization chambers, etc. Due to the different sizes of their chambers, it is necessary to reduce the uncertainty of absolute dose measurement, reduce the influence of factors such as scattering on the measurement results, and accurately simulate the absolute dose measurement scenario in radiotherapy. Utility Model Content

[0005] This invention aims to solve the technical problems existing in related technologies. To this end, this invention proposes a device for adjusting the beam irradiation field to simulate the beam environment during radiotherapy, obtaining a calibration factor for the absorbed dose of water in the ionization chamber used in radiotherapy, thereby achieving absolute dose measurement of radiotherapy equipment.

[0006] This utility model provides a device for adjusting the irradiation field of a beam, comprising:

[0007] The support assembly includes a base guide rail, a first support base, and a second support base.

[0008] A circular collimator is mounted on the first support base;

[0009] A square collimator is mounted on the second support base.

[0010] The support assembly also includes a seat plate that is slidably connected to the base guide rail, and the first support base and the second support base are fixed to the top surface of the seat plate.

[0011] According to the present invention, a device for adjusting the beam irradiation field is provided, wherein the square collimator comprises:

[0012] The frame is positioned above the second support base;

[0013] A transverse beam-limiting stop is disposed on the front side of the frame and is slidably connected to the frame;

[0014] A longitudinal beam-limiting stop is disposed on the rear side of the frame;

[0015] The two lateral beam-limiting apertures are relatively close or far apart in the horizontal direction, and the two longitudinal beam-limiting apertures are relatively close or far apart in the vertical direction, in order to form a square aperture.

[0016] According to the device for adjusting the beam irradiation field provided by this utility model, the square collimator further includes:

[0017] The first aperture guide rail is horizontally positioned at the top of the frame;

[0018] A lead screw, which is arranged parallel to and below the first aperture guide rail;

[0019] A slider, wherein the slider is provided with a threaded hole for connection with the lead screw drive;

[0020] The upper end of the slider is slidably connected to the first aperture guide rail, and the lower end of the slider is connected to the transverse beam-limiting aperture, which is used to drive the transverse beam-limiting aperture to move on the frame.

[0021] According to the present invention, a device for adjusting the beam irradiation field is provided, wherein the frame is configured as an arc-shaped curved panel, the first aperture guide rail is centered and aligned with the frame in the horizontal direction, and when the transverse beam limiting aperture moves along the frame, the transverse beam limiting aperture is tilted to the first aperture guide rail, forming an elevation angle with a variation range between 0° and 7°.

[0022] According to the present invention, a device for adjusting the beam illumination field is provided, wherein the circular collimator includes a large circular aperture and a small circular aperture, and the large circular aperture and the small circular aperture are respectively disposed on both sides of the square collimator;

[0023] The center points of the large circular aperture, the small circular aperture, and the square aperture are at the same height.

[0024] According to the present invention, a device for adjusting the irradiation field of a beam is provided, wherein the circular collimator includes six apertures of different diameters arranged in a conical shape, and the distance between adjacent apertures is 20 mm.

[0025] According to the present invention, a device for adjusting the beam illumination field is provided, wherein the large circular aperture and the small circular aperture can form a circular illumination field with a diameter greater than or equal to 200 mm at a distance of 1000 mm.

[0026] According to the present invention, a device for adjusting the beam irradiation field is provided, wherein the square aperture at 1000 mm can form a square field irradiation field with an adjustment range between 50 mm × 50 mm and 300 mm × 300 mm.

[0027] According to the present invention, a device for adjusting the beam irradiation field is provided, wherein the square collimator further includes a stepper motor, which is disposed above the first aperture guide rail;

[0028] The stepper motor is connected to the lead screw drive and is used to drive the transverse beam-limiting aperture to slide along the frame.

[0029] According to the present invention, a device for adjusting the beam irradiation field is provided, wherein both ends of the lead screw are provided with limit switches to limit the travel of the transverse beam limiting aperture on the first aperture guide rail.

[0030] The above-mentioned one or more technical solutions of this utility model have at least one of the following technical effects:

[0031] By mounting both the circular and square collimators on the base rail using a base plate, the size and specifications of the beam irradiation field can be easily selected, the beam environment during radiotherapy can be simulated, and the calibration factor for the water absorbed dose of the ionization chamber used in radiotherapy can be obtained, thus realizing the absolute dose measurement of the radiotherapy equipment.

[0032] In addition to the technical problems solved by this utility model, the technical features of the technical solutions constituted by this utility model, and the advantages brought about by these technical features, as described above, other technical features of this utility model and the advantages brought about by these technical features will be further explained in conjunction with the accompanying drawings, or can be learned through the practice of this utility model. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of this utility model or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 This is a schematic diagram of the overall structure of the device for adjusting the beam irradiation field provided in an embodiment of the present invention.

[0035] Figure 2 A schematic diagram of the structure of the square collimator provided in an embodiment of this utility model.

[0036] Figure 3 This is a schematic diagram of the structure of the small circular aperture provided in an embodiment of the present invention.

[0037] Figure 4 for Figure 2 A sectional view of section AA in the middle.

[0038] Figure 5 for Figure 2 A cross-sectional view of the longitudinal beam-limiting aperture in section BB.

[0039] Figure label:

[0040] 10. Support assembly; 11. Base rail; 12. First support base; 13. Second support base; 14. Seat plate; 20. Square collimator; 21. Frame; 22. First aperture rail; 23. Lateral beam-limiting aperture; 231. Groove; 232. Connecting flange; 233. Roller; 24. Longitudinal beam-limiting aperture; 25. Lead screw; 26. Slider; 27. Stepper motor; 28. Second aperture rail; 29. ​​Drive structure; 291. Servo motor; 292. Pulling component; 293. First screw; 294. Second screw; 295. Drive frame; 30. Circular collimator; 31. Large circular aperture; 32. Small circular aperture. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0042] In an embodiment of this utility model, a device for adjusting the beam irradiation field is described.

[0043] Please see Figures 1 to 3 As shown, the device for adjusting the beam irradiation field mainly includes a support assembly 10, a circular collimator 30, and a square collimator 20.

[0044] Specifically, the support assembly 10 is provided with a base guide rail 11, a first support base 12, and a second support base 13. A circular collimator 30 is mounted on the first support base 12. A square collimator 20 is mounted on the second support base 13.

[0045] The support assembly 10 also includes a base plate 14 that is slidably connected to the base guide rail 11. The first support base 12 and the second support base 13 are fixed to the top surface of the base plate 14. The base rail allows the circular collimator 30 and the square collimator 20 to move laterally together, thereby aligning the circular collimator 30 and the square collimator 20 with the center point of the beam.

[0046] Furthermore, the entire device is located outside the beam shutter switch. To achieve absolute dose measurement of the radiotherapy equipment, a Class I cobalt-60 radioactive source is used in conjunction. First, a water tank with dimensions of 30 cm × 30 cm × 15 cm is placed on the rotating platform, and the treatment level dosimeter is fixed in place. It is ensured that the water depth around the effective measurement point of the ionization chamber is greater than 5 cm. The dosimeter is positioned with a laser to align with the beam center point. The dosimeter is then connected to the main unit, the background is removed, and leakage current is measured.

[0047] Using either a circular collimator 30 or a square collimator 20, the size of the irradiation field is set through the operating software and adjusted via a stepper motor 27. After confirming all the above steps, the radiation source is extracted and irradiation begins. Data acquisition is performed in integration mode, with each acquisition time set to 20 seconds. Each group is measured 10 times, and the cumulative dose data is read and recorded. Due to the influence of factors such as temperature and air pressure, the measurement data needs to be corrected. The corrected average value is used as the measurement value at that point. The above experiment is repeated at least once for each range.

[0048] According to the calibration certificate of the standard metrology instrument, the corresponding conventional value of the irradiation field is measured using the same steps. Based on the ratio of the conventional value to the measured value, the corresponding calibration factor is given to complete the calibration of the dosimeter, thereby realizing the absolute dose measurement in the radiotherapy process.

[0049] In this embodiment, the circular collimator 30 and the square collimator 20 are mounted together on the base guide rail 11 via the base plate 14, which allows for convenient selection of the size and specifications of the beam irradiation field, simulation of the beam environment during radiotherapy, and thus obtaining the calibration factor of the water absorbed dose of the ionization chamber for radiotherapy, thereby realizing the absolute dose measurement of the radiotherapy equipment.

[0050] Based on the above embodiments, another embodiment of the present invention introduces a device for adjusting the beam irradiation field.

[0051] Please see Figure 2 , Figure 4 and Figure 5 As shown, the square collimator 20 mainly includes a frame 21, a transverse beam-limiting aperture 23, and a longitudinal beam-limiting aperture 24.

[0052] Specifically, frame 21 is positioned above the second support base 13. A transverse beam-limiting aperture 23 is positioned on the front side of frame 21 and is slidably connected to frame 21. A longitudinal beam-limiting aperture 24 is positioned on the rear side of frame 21.

[0053] Meanwhile, the transverse beam-limiting aperture 23 is also provided with a slot 231, a connecting flange 232, and a roller 233. The connecting flange 232 is installed on the top surface of the transverse beam-limiting aperture 23. The lower end of the connecting flange 232 is fixedly connected to the transverse beam-limiting aperture 23 by bolts. The upper end of the connecting flange 232 is provided with a pin. The pin extends horizontally from the connecting flange 232 to above the top surface of the frame 21. The roller 233 is rotatably sleeved on the pin. The roller 233 contacts the top surface of the frame 21 to allow the transverse beam-limiting aperture 23 to move smoothly along the frame 21. Both the transverse beam-limiting aperture 23 and the longitudinal beam-limiting aperture 24 are made of tungsten alloy with a total thickness of 95 mm arranged in a matrix. Each piece of tungsten alloy is 15 mm thick, and the spacing between adjacent pieces is 5 mm. The length of each piece of tungsten alloy is 220 mm.

[0054] Two transverse beam stops 23 are positioned relatively close to or far apart in the horizontal direction. Two longitudinal beam stops 24 are positioned relatively close to or far apart in the vertical direction. The transverse beam stops 23 and longitudinal beam stops 24 are perpendicularly interleaved to form a square beam stop.

[0055] Thus, by adjusting the spacing between the two transverse beam-limiting stops 23 and the spacing between the two longitudinal beam-limiting stops 24, the size of the square stop can be changed. Correspondingly, at 1000 mm, the square stop can form a square field of illumination with an adjustable range between 50 mm × 50 mm and 300 mm × 300 mm.

[0056] Furthermore, the square collimator 20 also includes a first aperture guide rail 22, a lead screw 25, and a slider 26. The first aperture guide rail 22 is horizontally disposed at the top of the frame 21. The lead screw 25 is disposed parallel below the first aperture guide rail 22. The slider 26 is provided with a threaded hole for transmission connection with the lead screw 25.

[0057] The upper end of slider 26 is slidably connected to the first aperture guide rail 22. The lower end of slider 26 is connected to the transverse beam-limiting aperture 23, which is used to drive the transverse beam-limiting aperture 23 to move on the frame 21.

[0058] Furthermore, the square collimator 20 also includes a stepper motor 27. The stepper motor 27 is positioned above the first aperture guide rail 22.

[0059] The stepper motor 27 is connected to the lead screw 25 for driving the transverse beam-limiting aperture 23 to slide along the frame 21.

[0060] Specifically, the left end of the lead screw 25 has a clockwise rotating threaded structure, and the right end of the lead screw 25 has a counterclockwise rotating threaded structure. The sliders 26 fitted at both ends of the lead screw 25 each have threaded holes corresponding to the direction of rotation. Thus, the stepper motor 27, by driving the lead screw 25 to rotate, can respectively move the sliders 26 fitted at both ends of the lead screw 25 closer together or further apart.

[0061] Preferably, the output shaft of the stepper motor 27 is fitted with a drive sprocket. A driven sprocket is located in the middle of the lead screw 25. The drive sprocket and the driven sprocket are connected by a chain drive.

[0062] Furthermore, limit switches are provided at both ends of the lead screw 25 to limit the travel of the transverse beam-limiting aperture 23 on the first aperture guide rail 22.

[0063] like Figure 2 and Figure 4 As shown, the frame 21 is configured as an arc-shaped curved panel with a window extending through both sides in its center. Two transverse beam-limiting stops 23 are located in front of the arc-shaped curved panel and are positioned above and below the window, respectively. Two longitudinal beam-limiting stops 24 are located behind the arc-shaped curved panel and are positioned to the left and right of the window, respectively. A first beam-limiting guide rail 22 extends in a straight line. The first beam-limiting guide rail 22 is horizontally aligned with the frame 21. As the transverse beam-limiting stops 23 move along the frame 21, they tilt relative to the first beam-limiting guide rail 22, forming an elevation angle ranging from 0° to 7°. Furthermore, as the transverse beam-limiting stops 23 move along the frame 21, the elevation angle changes synchronously with the size of the illumination field.

[0064] When the transverse beam-limiting aperture 23 moves along the frame 21, its trajectory is an arc curve, while when the slider 26 moves along the first aperture guide rail 22, its trajectory is a straight line. When the slider 26 is driven by the lead screw 25, misalignment will occur between the transverse beam-limiting aperture 23 and the slider 26, causing the transverse beam-limiting aperture 23 to move unevenly, or even causing the slider 26 to deform and be damaged.

[0065] like Figure 4As shown, the slot 231 is disposed on the top surface of the transverse beam-limiting aperture 23. The slot 231 is elongated. Furthermore, the length direction of the slot 231 is perpendicular to the length direction of the first aperture guide rail 22. Thus, by sliding the lower end of the slider 26 within the slot 231, the transverse beam-limiting aperture 23, which moves along an arc curve, can be adapted to the slider 26, which moves along a straight line.

[0066] In addition, combined Figure 5 As shown, the square collimator 20 also includes a second aperture guide rail 28 disposed on the base plate 14. The second aperture guide rail 28 extends vertically upward from the base plate 14.

[0067] Two second aperture guide rails 28 are mounted at intervals on the rear side of the frame 21. Two longitudinal beam-limiting apertures 24 are slidably mounted between the two second aperture guide rails 28. The driving structure 29 for moving the two longitudinal beam-limiting apertures 24 closer or further apart in the vertical direction is located below the longitudinal beam-limiting apertures 24.

[0068] The drive structure 29 includes a servo motor 291, a tension member 292, a first screw 293, a second screw 294, and a drive frame 295.

[0069] The tension member 292 is configured as a U-shaped connecting rod. The upper end of the tension member 292 consists of two parallel, spaced-apart vertical rods. The lower end of the tension member 292 is a horizontal rod connecting the two vertical rods. The two vertical rods are fixedly connected to the upper longitudinal beam-limiting aperture 24. The horizontal rod is movably connected to the first screw 293 via a threaded structure. Therefore, rotating the first screw 293 can move the upper longitudinal beam-limiting aperture 24 up and down.

[0070] The lower longitudinal beam-limiting aperture 24 is provided with a threaded channel. The upper end of the second screw 294 is connected to the threaded channel, and rotating the second screw 294 can drive the lower longitudinal beam-limiting aperture 24 to move up and down.

[0071] Furthermore, the drive frame 295 is mounted on the base plate 14. The first screw 293 and the second screw 294 are rotatably mounted on the drive frame 295. Driven gears are mounted on the lower ends of both the first screw 293 and the second screw 294. A servo motor 291 is mounted on the drive frame 295. A drive gear is mounted on the output shaft of the servo motor 291.

[0072] The driving gear meshes with one of the two driven gears, and the two driven gears mesh with each other, so that the first screw 293 and the second screw 294 always rotate in opposite directions, thereby driving the two longitudinal beam-limiting apertures 24 to move closer or further apart in the vertical direction.

[0073] Based on the above embodiments, another embodiment of the present invention introduces a device for adjusting the beam irradiation field.

[0074] Please see Figure 1 and Figure 3 As shown, the circular collimator 30 includes a large circular aperture 31 and a small circular aperture 32. The large circular aperture 31 and the small circular aperture 32 are respectively disposed on both sides of the square collimator 20.

[0075] The center points of the large circular aperture 31, the small circular aperture 32, and the square aperture are at the same height.

[0076] Furthermore, the circular collimator 30 includes six apertures of different diameters arranged in a conical shape, with a spacing of 20 mm between adjacent apertures. Specifically, each aperture is 15 mm thick. The diameters of these six apertures gradually increase along the beam direction, and the circular apertures are positioned close to the collimator to reduce scattering.

[0077] The large circular aperture 31 has a maximum design diameter of 115 mm. The small circular aperture 32 has a maximum design diameter of 70 mm. Both the large circular aperture 31 and the small circular aperture 32 are made of tungsten alloy with a total thickness of 220 mm.

[0078] The circular collimator 30 consists of six apertures of different diameters arranged in a conical shape. Each aperture is 20 mm thick, and the gaps between them are 20 mm. Each gap acts as a trap for the scattered rays from the edge of the previous aperture. Preferably, the outermost aperture is made of graphite and is 3 mm thick, with an aperture slightly larger than the beam cross-section at that point.

[0079] In this embodiment, the circular collimator 30 adopts a conical design, which can ensure beam uniformity and reduce the influence of collimation shielding scattering, meeting the standard requirements of ISO 4037-1.

[0080] Furthermore, the large circular aperture 31 and the small circular aperture 32 can form a circular illumination field with a diameter of 200 mm or more at 1000 mm.

[0081] In the description of the embodiments of this utility model, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this utility model. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0082] In the description of the embodiments of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this utility model based on the specific circumstances.

[0083] In this embodiment of the utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0084] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms are not limited to the same embodiments or examples. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0085] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. An apparatus for adjusting a beam field of irradiation, characterized in that, include: The support assembly (10) is provided with a base guide rail (11), a first support base (12), and a second support base (13). A circular collimator (30) is mounted on the first support base (12); A square collimator (20) is mounted on the second support base (13). The support assembly (10) is further provided with a seat plate (14) that is slidably connected to the base guide rail (11), and the first support base (12) and the second support base (13) are fixed on the top surface of the seat plate (14).

2. The device for adjusting a beam field of view according to claim 1, characterized in that, The square collimator (20) includes: The frame (21) is positioned above the second support base (13); A transverse beam-limiting stop (23) is disposed on the front side of the frame (21) and is slidably connected to the frame (21); A longitudinal beam-limiting stop (24) is disposed on the rear side of the frame (21); The two lateral beam-limiting stops (23) are relatively close or far apart in the horizontal direction, and the two longitudinal beam-limiting stops (24) are relatively close or far apart in the vertical direction, for forming a square beam-limiting stop.

3. The device for adjusting a beam field of view according to claim 2, characterized in that, The square collimator (20) also includes: The first aperture guide rail (22) is horizontally set at the top of the frame (21); A lead screw (25) is arranged parallel to the bottom of the first aperture guide rail (22); The slider (26) is provided with a threaded hole for transmission connection with the lead screw (25); The upper end of the slider (26) is slidably connected to the first aperture guide rail (22), and the lower end of the slider (26) is connected to the transverse beam-limiting aperture (23) to drive the transverse beam-limiting aperture (23) to move on the frame (21).

4. The device for adjusting a beam field of view according to claim 3, characterized in that, The frame (21) is set as an arc-shaped curved panel. The first aperture guide rail (22) is centered and aligned with the frame (21) in the horizontal direction. When the transverse beam-limiting aperture (23) moves along the frame (21), the transverse beam-limiting aperture (23) is tilted to the first aperture guide rail, forming an elevation angle with a variation range between 0° and 7°.

5. The apparatus for adjusting the beam irradiation field according to any one of claims 2 to 4, characterized in that, The circular collimator (30) includes a large circular aperture (31) and a small circular aperture (32), which are respectively disposed on both sides of the square collimator (20); The center point of the large circular aperture (31), the center point of the small circular aperture (32), and the center point of the square aperture are at the same height.

6. The device for adjusting a beam field of view of claim 5, wherein, The circular collimator (30) includes six apertures of different diameters arranged in a conical shape, with a spacing of 20 mm between adjacent apertures.

7. The device for adjusting a beam field of view of claim 5, wherein, The large circular aperture (31) and the small circular aperture (32) can form a circular illumination field with a diameter greater than or equal to 200 mm at 1000 mm.

8. The device for adjusting a beam field of view of claim 7, wherein, The square aperture at 1000 mm can form a square field of illumination with an adjustable range between 50 mm × 50 mm and 300 mm × 300 mm.

9. The device for adjusting a beam field of view of claim 3, wherein, The square collimator (20) also includes a stepper motor (27) disposed above the first aperture guide rail (22); The stepper motor (27) is connected to the lead screw (25) for driving the transverse beam-limiting aperture (23) to slide along the frame (21).

10. The device for adjusting a beam field of view of claim 9, wherein, Both ends of the lead screw (25) are equipped with limit switches to limit the travel of the transverse beam-limiting aperture (23) on the first aperture guide rail (22).

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