A collimator precision measuring device and measuring method for a radiotherapy apparatus

Abstract

This invention discloses a collimator accuracy measurement device and method for radiotherapy equipment, belonging to the technical field of radiotherapy equipment. The device, through the combination of a laser positioning tracker and a measuring fixture, achieves high-precision measurement of the relative position of the secondary collimator and the primary collimator. The laser positioning tracker can accurately capture the position and trajectory of the target ball, ensuring the accuracy of the measurement data. The measuring fixture is designed to effectively measure the parallelism of the rotational trajectories of the three cylinders to the absolute horizontal plane, as well as the coaxiality of the central axes of the secondary and primary collimators, thereby ensuring that the accuracy of the measurement results meets the treatment requirements. By ensuring precise alignment of the secondary and primary collimators, this invention can significantly improve the accuracy and effectiveness of radiotherapy. Precise collimator alignment can optimize beam distribution, ensuring that high-dose irradiation is precisely focused on the tumor lesion area while reducing damage to surrounding normal tissues.

Description

Technical Field

[0001] This invention relates to the technical field of radiotherapy equipment, and more specifically, to a collimator accuracy measuring device and method for radiotherapy equipment. Background Technology

[0002] In the field of radiotherapy equipment technology, ensuring precise collimator alignment is crucial for achieving treatment accuracy. With continuous advancements in radiotherapy technology, traditional radiotherapy methods are gradually evolving towards precision radiosurgery, a technique that emphasizes "precise diagnosis, precise localization, precise planning, and precise treatment" of tumors. Precision stereotactic radiotherapy delivers high-dose irradiation to the tumor through 1-5 fractions, significantly improving local tumor control rates while reducing complications in normal tissues and enhancing treatment outcomes. The core of this technology lies in expanding and optimizing the beam distribution in the treatment space, employing multiple non-coplanar high-dose small-field irradiation, precisely focusing on the tumor lesion area. This allows the dose distribution to rapidly decrease at the target edge, minimizing damage to surrounding normal tissues and greatly improving the adaptability and effectiveness of radiotherapy.

[0003] During treatment, the coaxiality of the inner bores of the primary and secondary collimators has a decisive impact on ensuring treatment efficacy and safety. Precise matching of the inner bore coaxiality is a key factor in achieving efficient treatment and reducing side effects. Therefore, ensuring the coaxiality of the primary and secondary collimators during the mechanical assembly stage becomes a crucial technical challenge. Existing techniques for measuring the relative position of the secondary and primary collimators mainly rely on manual adjustment and visual inspection. This method is not only limited in accuracy and inefficient but also susceptible to human error. Because the precision of manual adjustment is difficult to guarantee, inaccurate collimator switching may occur, affecting treatment efficacy and potentially causing unnecessary harm to the patient. Summary of the Invention

[0004] This invention addresses the technical problems of low accuracy and slow efficiency in measuring the relative position of the secondary collimator and the primary collimator in existing technologies by providing a collimator accuracy measuring device and method for radiotherapy equipment.

[0005] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:

[0006] A collimator accuracy measuring device for a radiotherapy equipment, the radiotherapy equipment comprising a primary collimator, a secondary collimator automatic switching mechanism, and at least one secondary collimator, wherein:

[0007] The automatic switching mechanism for the secondary collimator includes a fixed plate, a drive assembly, and a moving plate. The primary collimator is installed at one end of the fixed plate, and the moving plate is installed at the other end of the fixed plate.

[0008] The moving disk is also provided with a cylinder position corresponding to each of the secondary collimators. Each of the secondary collimators is installed in each of the cylinder positions. The driving component is configured to drive the moving disk to rotate at a specified angle to adjust the position of the secondary collimator.

[0009] The collimator accuracy measuring device includes a level, a laser positioning and tracking instrument, laser positioning and tracking instrument accessories, and measuring fixtures, wherein:

[0010] The level is used to calibrate the absolute level of the lower end face of the primary collimator;

[0011] The measuring fixture includes a base and a mounting bracket connected to the base, the base being configured to be embedded in the cylinder.

[0012] The laser positioning and tracking device accessory includes a first target ball and a second target ball. The measuring fixture is set vertically during measurement, and the first target ball and the second target ball are installed at intervals along the height direction on the mounting bracket.

[0013] The laser positioning and tracking device is used to emit a laser beam and receive reflected signals. The surfaces of the first target ball and the second target ball are provided with reflective layers to reflect the laser beam back to the laser positioning and tracking device. The laser positioning and tracking device establishes communication with the first target ball and the second target ball through optical coupling to determine the position coordinates of the first target ball and the second target ball in three-dimensional space.

[0014] Furthermore, the laser positioning and tracking device includes:

[0015] An optical receiver is used to receive reflected signals from the first target ball and the second target ball;

[0016] The processor is used to convert the reflected signal into an electrical signal and perform data processing to output the position information of the first target ball and the second target ball.

[0017] Furthermore, the driving component is a stepper motor.

[0018] Furthermore, the number of cylinder positions is 3, and the 3 cylinder positions are evenly distributed on the circumference of the moving plate at equal intervals of 120°, with the central angle between adjacent cylinder positions being 120°.

[0019] Furthermore, the models of the secondary collimators are different from each other, and the first target ball and the second target ball are the same in size and shape.

[0020] A method for measuring the accuracy of a collimator in a radiotherapy device, based on the aforementioned collimator accuracy measuring device for a radiotherapy device, the method comprising the following steps:

[0021] Place the level on the lower end face of the primary collimator, calibrate the absolute level of the lower end face of the primary collimator, and establish the absolute level plane of the primary collimator; use a laser positioning tracker to find the central axis of the primary collimator; the absolute level plane is perpendicular to the central axis;

[0022] The automatic switching mechanism of the secondary collimator is installed at the lower end of the primary collimator, and the measuring fixture is sequentially embedded in each of the cylinder positions; the moving disk is driven to rotate one revolution by the driving component, and the parallelism between the trajectory circle formed by the rotation trajectory of the first target ball and / or the second target ball and the absolute horizontal plane is measured by the laser positioning tracker.

[0023] Furthermore, the method for calculating the parallelism is as follows:

[0024] Calculate the vertical distance between each sampling point on each of the trajectory circles and the absolute horizontal plane;

[0025] The difference between the maximum and minimum vertical distances is used as the parallelism deviation.

[0026] If the parallelism deviation is less than or equal to a preset threshold, then the installation of the secondary collimator is determined to meet the parallelism requirements.

[0027] Furthermore, the collimator accuracy measurement method also includes:

[0028] Based on the parallelism measurement results, the position and angle of each cylinder position are adjusted respectively;

[0029] The coaxiality of each cylinder position with the central axis of the primary collimator is measured using the laser positioning and tracking instrument.

[0030] Furthermore, measuring the coaxiality of each of the aforementioned cylinder positions with the central axis of the primary collimator specifically involves:

[0031] The rotation trajectory of the first target ball forms a first trajectory circle, and the rotation trajectory of the second target ball forms a second trajectory circle. The center of the first trajectory circle and the center of the second trajectory circle are connected by a concentric axis.

[0032] Calculate the distance and angular deviation between the concentric axis and the central axis of the primary collimator;

[0033] Adjust the position of each cylinder according to the calculation results, so that the distance and angle deviation between the concentric axis and the central axis are within the preset threshold range.

[0034] Furthermore, the diameter of the circular surface formed by the rotational trajectory of the first target ball is d1, and the diameter of the circular surface formed by the rotational trajectory of the second target ball is d2. The collimator accuracy measurement method includes:

[0035] By comparing the sizes of diameter d1 and diameter d2, the installation position deviation of each cylinder position is determined;

[0036] By comparing the distances from diameters d1 and d2 to the central axis, it is determined whether the eccentricity between the primary collimator and the moving disk is within the preset tolerance range.

[0037] Compared with the prior art, the beneficial effects of the technical solution of the present invention are:

[0038] This invention provides a collimator accuracy measurement device and method for radiotherapy equipment. The device, through the combination of a laser positioning tracker and a measuring fixture, achieves high-precision measurement of the relative position of the secondary collimator and the primary collimator. The laser positioning tracker accurately captures the position and trajectory of the target ball, ensuring the accuracy of the measurement data. The measuring fixture is designed to effectively measure the parallelism of the rotational trajectories of the three cylinder positions to the absolute horizontal plane, as well as the coaxiality of the central axes of the secondary and primary collimators, thereby ensuring that the accuracy of the measurement results meets treatment requirements. The measurement process of this invention employs a laser tracker and automated data acquisition technology, reducing human intervention and operational errors. Traditional manual adjustment and visual inspection methods are not only inefficient but also susceptible to human factors, while this invention significantly improves measurement efficiency and reliability through automated measurement and data analysis. This invention simplifies the measurement and adjustment process of the relative position of the secondary and primary collimators through standardized measurement methods and fixture design. The combined use of the measuring fixture and laser tracker makes operation more intuitive and convenient, reducing not only the difficulty of operation but also the training costs and time for operators. By ensuring precise alignment between the secondary collimator and the primary collimator, this invention significantly improves the accuracy and effectiveness of radiotherapy. Precise collimator alignment optimizes beam distribution, ensuring high-dose irradiation is accurately focused on the tumor lesion area while minimizing damage to surrounding healthy tissues. This is crucial for improving local tumor control and reducing complication rates. The measurement fixtures and methods of this invention offer high versatility and compatibility, applicable to various types of radiotherapy equipment. This flexibility allows for wide application in different medical scenarios, meeting the calibration needs of diverse devices and demonstrating high practical value. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a schematic diagram of the measuring fixture in the collimator accuracy measuring device provided in one embodiment of this application, installed on a radiotherapy device, from a first-view perspective.

[0041] Figure 2 This is a schematic diagram of the measuring fixture in the collimator accuracy measuring device provided in one embodiment of this application, installed on a radiotherapy device, from a second perspective.

[0042] Figure 3 This is a three-dimensional structural schematic diagram of the measuring fixture in the collimator accuracy measuring device provided in one embodiment of this application;

[0043] Explanation of markings in the diagram:

[0044] 1. Primary collimator;

[0045] 2. Automatic switching mechanism for the secondary collimator; 21. Fixed plate; 22. Moving plate; 221. Cylinder position;

[0046] 3. Secondary collimator;

[0047] 11. Measuring fixture; 111. Base; 112. Mounting bracket;

[0048] 12. First target ball; 13. Second target ball. Detailed Implementation

[0049] The following description provides numerous specific details to offer a more thorough understanding of this application. However, it will be apparent to those skilled in the art that this application can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described to avoid confusion with this application.

[0050] It should be understood that this application can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of this application to those skilled in the art. In the drawings, for clarity, the dimensions and relative dimensions of layers and regions may be exaggerated. The same reference numerals denote the same elements throughout.

[0051] In the description of this invention, it should be understood that the terms "left side," "right side," "upper part," "lower part," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention 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. The specific dimensions used in the embodiments are only for illustrating the technical solutions and do not limit the scope of protection of this invention. It will be understood by those skilled in the art that some well-known structures and their descriptions may be omitted in the accompanying drawings.

[0052] Unless otherwise expressly specified and limited, the terms "installation," "setting," "connection," and "fixation" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0053] To fully understand this application, a detailed structure will be presented in the following description to illustrate the technical solutions proposed in this application. Preferred embodiments of this application are described in detail below; however, in addition to these detailed descriptions, this application may have other implementation methods.

[0054] Example 1:

[0055] like Figure 1-3 As shown, the present invention provides a technical solution:

[0056] A collimator accuracy measuring device for a radiotherapy equipment, the radiotherapy equipment comprising a primary collimator 1, a secondary collimator automatic switching mechanism 2, and at least one secondary collimator 3, wherein:

[0057] The secondary collimator automatic switching mechanism 2 includes a fixed plate 21, a drive assembly, and a moving plate 22. The primary collimator 1 is installed at one end of the fixed plate 21, and the moving plate 22 is installed at the other end of the fixed plate 21.

[0058] The moving disk 22 is also provided with a cylinder position 221 corresponding to each of the secondary collimators 3. Each of the secondary collimators 3 is installed in each of the cylinder positions 221. The driving component is configured to drive the moving disk 22 to rotate at a specified angle to adjust the position of the secondary collimators 3.

[0059] The collimator accuracy measuring device includes a level, a laser positioning and tracking instrument, laser positioning and tracking instrument accessories, and measuring fixture 11, wherein:

[0060] The level is used to calibrate the absolute level of the lower end face of the primary collimator 1;

[0061] The measuring fixture 11 includes a base 111 and a mounting bracket 112 connected to the base 111. The base 111 is configured to be embedded in the cylinder position 221. The measuring fixture 11 is used to measure the parallelism between the circular surface formed by the rotation trajectory of each cylinder position 221 and the absolute horizontal plane, and is also used to measure the coaxiality between each cylinder position 221 of the secondary collimator 3 and the central axis of the primary collimator 1.

[0062] The laser positioning and tracking device accessory includes a first target ball 12 and a second target ball 13. The measuring fixture 11 is set vertically during measurement. The first target ball 12 and the second target ball 13 are installed at intervals along the height direction on the mounting bracket 112.

[0063] The laser positioning and tracking device is used to emit a laser beam and receive reflected signals. The surfaces of the first target ball 12 and the second target ball 13 are provided with reflective layers to reflect the laser beam back to the laser positioning and tracking device. The laser positioning and tracking device establishes communication with the first target ball 12 and the second target ball 13 through optical coupling to determine the position coordinates of the first target ball 12 and the second target ball 13 in three-dimensional space.

[0064] The number of cylinder positions 221 is 3.

[0065] The working principle of this collimator accuracy measuring device is as follows:

[0066] 1. Determining the central axis of primary collimator 1:

[0067] Use a level to calibrate the absolute level of the lower end face of the primary collimator 1;

[0068] Use a laser positioning and tracking instrument to locate the center axis of primary collimator 1;

[0069] Using a laser positioning and tracking device, the absolute horizontal plane coordinate system is mapped onto the target sphere of the horizontal reference plane to establish the absolute horizontal plane of the primary collimator 1.

[0070] The absolute position perpendicular to the mechanical axis of the primary collimator 1 is obtained in the software of the laser positioning and tracking instrument, which serves as the reference for the following measurements.

[0071] 2. Installation and adjustment of the secondary collimator 3:

[0072] Install the secondary collimator 3 onto the primary collimator 1, and re-measure and confirm the position of the central axis of the primary collimator 1;

[0073] The parallelism between the circular surface formed by the rotational trajectories of the three cylinder positions 221 in the secondary collimator 3 and the absolute horizontal plane is measured using a laser tracking positioner and measuring fixture 11.

[0074] Based on the measurement results, adjust the position and angle of the three cylinder positions 221 to ensure that the diameter and roundness of the trajectory circle meet the tolerance requirements; measure the parallelism between the circular surface formed by the target ball's rotation trajectory (taking several points at equal intervals of 30° to form the circular surface) and the absolute horizontal plane (established in step 1) when the three cylinder positions 221 are installed in the measuring fixture 11; adjust the position and angle of the three cylinder positions 221 respectively based on the measurement results.

[0075] By comparing the diameter and roundness of the trajectory circles, the deviation should meet the allowable requirements (the deviation of the diameters d1 and d2 of the upper and lower trajectory circles should be 0.1 mm, and the roundness should be 0.05 mm).

[0076] 3. Coaxiality measurement and adjustment:

[0077] The coaxiality of the three cylinder positions 221 in the secondary collimator 3 with the central axis of the primary collimator 1 is measured using a laser tracking and positioning instrument and measuring fixture 11.

[0078] Adjust the position of the secondary collimator 3 according to the measurement results so that the distance between the two axes meets the tolerance requirements. In the patient plane, the deviation of the distance between the two axes does not exceed 0.15mm.

[0079] In this embodiment, by using a level and a laser positioning tracker, the device can accurately calibrate the absolute level of the primary collimator 1, and measure the position coordinates of the secondary collimator 3 using the first target ball 12 and the second target ball 13 in the laser positioning tracker accessory. This high-precision measurement method greatly reduces human error and improves the accuracy and efficiency of the measurement. The drive component in the secondary collimator automatic switching mechanism 2 can drive the moving disk 22 to rotate at a specified angle, thereby automatically adjusting the position of the secondary collimator 3. This automated design not only reduces the need for manual operation, but also improves the ease of use and operational efficiency of the equipment.

[0080] Example 2:

[0081] Based on Example 1, and referring to Figure 1-3 The laser positioning and tracking device includes:

[0082] An optical receiver is used to receive reflected signals from the first target ball 12 and the second target ball 13;

[0083] The processor is used to convert the reflected signal into an electrical signal and perform data processing to output the position information of the first target ball 12 and the second target ball 13.

[0084] Furthermore, the driving component is a stepper motor.

[0085] Furthermore, the three cylinder positions 221 are evenly distributed on the circumference of the moving disk 22 at equal intervals of 120°, and the central angle between adjacent cylinder positions 221 is 120°.

[0086] Furthermore, the models of the secondary collimators 3 are different from each other, and the first target ball 12 and the second target ball 13 have the same size and shape.

[0087] Specifically, the method of using this collimator accuracy measuring device is as follows:

[0088] The central axis of the primary collimator 1 is determined using a laser positioning and tracking instrument, and a coordinate system is established to determine the position of the central axis in the coordinate system.

[0089] Using a laser tracker and coaxiality measuring fixture 11, rotate the collimator switching device one revolution to measure the trajectory diameter d1 and roundness of the outer target ball in the fixture. The roundness can be used to determine whether there is a deviation in the measurement result; the trajectory circle diameter deviation is required to be <0.1mm, and the roundness deviation is required to be <0.05mm.

[0090] Using a laser tracker and coaxiality measuring fixture 11, rotate the collimator switching device one revolution to measure the trajectory diameter d2 and the roundness of the inner target ball in the fixture. This will help determine if there is any deviation in the measurement results. The deviation of the trajectory circle diameter should be 0 < 0.1 mm, and the roundness deviation should be < 0.05 mm.

[0091] By comparing the sizes of d1 and d2, the installation position deviation of the mounting cylinder of the secondary collimator 3 can be determined.

[0092] By comparing the distances d1 / d2 to the central axis of the primary collimator 1, it is determined whether the eccentric distance between the primary collimator 1 and the collimator switching device moving disk 22 is consistent with the design value; the distance deviation requirement is <0.15mm.

[0093] Example 3:

[0094] This invention provides a technical solution:

[0095] A method for measuring the accuracy of a collimator in a radiotherapy device, based on the aforementioned collimator accuracy measuring device for a radiotherapy device, the method comprising the following steps:

[0096] Place the level on the lower end face of the primary collimator 1 to calibrate the absolute level of the lower end face of the primary collimator 1 and establish the absolute level plane of the primary collimator 1; use a laser positioning tracker to find the central axis of the primary collimator 1; the absolute level plane is perpendicular to the central axis.

[0097] The secondary collimator automatic switching mechanism 2 is installed at the lower end of the primary collimator 1, and the measuring fixture 11 is sequentially embedded in each of the cylinder positions 221; the moving disk 22 is driven to rotate one revolution by the driving component, and the parallelism between the trajectory circle formed by the rotation trajectory of the first target ball 12 and / or the second target ball 13 and the absolute horizontal plane is measured by the laser positioning tracker.

[0098] Example 4:

[0099] Based on Example 3, the method for calculating the parallelism is as follows:

[0100] Calculate the vertical distance between each sampling point on each of the trajectory circles and the absolute horizontal plane;

[0101] The difference between the maximum and minimum vertical distances is used as the parallelism deviation.

[0102] If the parallelism deviation is less than or equal to the preset threshold, it is determined that the installation of the secondary collimator 3 meets the parallelism requirements.

[0103] Furthermore, the collimator accuracy measurement method also includes:

[0104] Based on the parallelism measurement results, the position and angle of each of the cylinder positions 221 are adjusted respectively;

[0105] The coaxiality of each of the cylinder positions 221 and the central axis of the primary collimator 1 is measured using the laser positioning and tracking instrument.

[0106] Furthermore, measuring the coaxiality of each of the aforementioned cylinder positions 221 with the central axis of the primary collimator 1 specifically involves:

[0107] The rotation trajectory of the first target ball 12 forms a first trajectory circle, and the rotation trajectory of the second target ball 13 forms a second trajectory circle. The center of the first trajectory circle and the center of the second trajectory circle are connected by a concentric axis.

[0108] Calculate the distance and angular deviation between the concentric axis and the central axis of the primary collimator 1;

[0109] Adjust the position of each cylinder 221 according to the calculation results so that the distance and angle deviation between the concentric axis and the central axis are within the preset threshold range.

[0110] Furthermore, the methods for calculating coaxiality include:

[0111] Calculate the radial offset between the center of the first trajectory circle, the center of the second trajectory circle, and the central axis of the primary collimator 1;

[0112] The maximum value of the radial offset is taken as the coaxiality deviation.

[0113] Furthermore, the diameter of the circular surface formed by the rotation trajectory of the first target ball 12 is d1, and the diameter of the circular surface formed by the rotation trajectory of the second target ball 13 is d2. The collimator accuracy measurement method includes:

[0114] By comparing the sizes of diameter d1 and diameter d2, the installation position deviation of each of the cylinder positions 221 is determined;

[0115] By comparing the distances from diameter d1 and diameter d2 to the central axis, it is determined whether the eccentricity distance between the primary collimator 1 and the moving disk 22 is within the preset tolerance range.

[0116] Example 5:

[0117] This invention provides a technical solution:

[0118] A method for measuring the accuracy of a collimator in a radiotherapy device, based on the aforementioned collimator accuracy measuring device for a radiotherapy device, the method comprising the following steps:

[0119] S1, Begin;

[0120] S2. Use a laser positioning tracker to locate the center axis of the primary collimator 1;

[0121] S3. Map the absolute horizontal plane coordinate system onto the target ball on the robot base;

[0122] S4. Establish the robot's absolute horizontal plane in the laser positioning and tracking system;

[0123] S5. Remeasure and confirm the position of the central axis of the primary collimator 1;

[0124] S6. Measure the parallelism between the circular surface formed by the rotation trajectory of the three cylinder positions 221 and the absolute horizontal plane using a laser positioning tracker and measuring fixture 11.

[0125] S7. Determine whether the parallelism requirement is met. If not, proceed to S71; if yes, proceed to S8.

[0126] S71. Adjust the position and angle of the three cylinder positions 221 according to the measurement results to ensure that the diameter and roundness of the trajectory circle meet the tolerance requirements; if they meet the requirements, proceed to S8.

[0127] S8. Measure the concentricity of the three cylinder positions 221 with the central axis of the primary collimator 1 using a laser tracking positioning instrument and measuring fixture 11.

[0128] S9. Determine if the concentricity requirement is met; otherwise, execute S91; otherwise, execute S10.

[0129] S91. Adjust the position of the entire three-station according to the measurement results so that the distance between the two axes meets the tolerance requirements; if it does, proceed to S10.

[0130] S10, End.

[0131] All the devices (parts whose specific structures are not specified) selected in this application are general standard parts or parts known to those skilled in the art. Their structures and principles can be learned by those skilled in the art through technical manuals or conventional experimental methods.

[0132] Although exemplary embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above exemplary embodiments are merely illustrative and are not intended to limit the scope of this application. Various changes and modifications can be made therein by those skilled in the art without departing from the scope and spirit of this application. All such changes and modifications are intended to be included within the scope of this application as claimed in the appended claims.

[0133] Similarly, it should be understood that, in order to simplify this application and aid in understanding one or more aspects of the application, various features of this application may sometimes be grouped together in a single embodiment, figure, or description thereof in the description of exemplary embodiments of this application. However, this approach should not be construed as reflecting an intention that the claimed application requires more features than are expressly recited in each claim. Rather, as reflected in the corresponding claims, the point of application is that the corresponding technical problem can be solved with fewer features than all of a single disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of this application.

[0134] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features but not others included in other embodiments, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

[0135] It should be noted that the above embodiments are illustrative of this application and not limiting of it, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names.

Claims

1. A collimator accuracy measuring device for radiotherapy equipment, characterized in that, The radiotherapy equipment includes a primary collimator, a secondary collimator automatic switching mechanism, and at least one secondary collimator, wherein: The automatic switching mechanism for the secondary collimator includes a fixed plate, a drive assembly, and a moving plate. The primary collimator is installed at one end of the fixed plate, and the moving plate is installed at the other end of the fixed plate. The moving disk is also provided with a cylinder position corresponding to each of the secondary collimators. Each of the secondary collimators is installed in each of the cylinder positions. The driving component is configured to drive the moving disk to rotate at a specified angle to adjust the position of the secondary collimator. The collimator accuracy measuring device includes a level, a laser positioning and tracking instrument, laser positioning and tracking instrument accessories, and measuring fixtures, wherein: The level is used to calibrate the absolute level of the lower end face of the primary collimator; The measuring fixture includes a base and a mounting bracket connected to the base, the base being configured to be embedded in the cylinder. The laser positioning and tracking device accessory includes a first target ball and a second target ball. The measuring fixture is set vertically during measurement, and the first target ball and the second target ball are installed at intervals along the height direction on the mounting bracket. The laser positioning and tracking device is used to emit a laser beam and receive reflected signals. The surfaces of the first target ball and the second target ball are provided with reflective layers to reflect the laser beam back to the laser positioning and tracking device. The laser positioning and tracking device establishes communication with the first target ball and the second target ball through optical coupling to determine the position coordinates of the first target ball and the second target ball in three-dimensional space.

2. The collimator accuracy measuring device for radiotherapy equipment according to claim 1, characterized in that, The laser positioning and tracking device includes: An optical receiver is used to receive reflected signals from the first target ball and the second target ball; The processor is used to convert the reflected signal into an electrical signal and perform data processing to output the position information of the first target ball and the second target ball.

3. The collimator accuracy measuring device for radiotherapy equipment according to claim 1, characterized in that, The drive component is a stepper motor.

4. The collimator accuracy measuring device for radiotherapy equipment according to claim 1, characterized in that, The number of cylinder positions is 3, and the 3 cylinder positions are evenly distributed on the circumference of the moving plate at equal intervals of 120°, with the central angle between adjacent cylinder positions being 120°.

5. The collimator accuracy measuring device for radiotherapy equipment according to claim 1, characterized in that, The models of the secondary collimators are different from each other, and the first target ball and the second target ball are the same in size and shape.

6. A method for measuring the accuracy of a collimator in a radiotherapy device, characterized in that, The collimator accuracy measuring device for radiotherapy equipment according to any one of claims 1-5, wherein the collimator accuracy measuring method comprises the following steps: Place the level on the lower end face of the primary collimator, calibrate the absolute level of the lower end face of the primary collimator, and establish the absolute level plane of the primary collimator; use a laser positioning tracker to find the central axis of the primary collimator; the absolute level plane is perpendicular to the central axis; The automatic switching mechanism of the secondary collimator is installed at the lower end of the primary collimator, and the measuring fixture is sequentially embedded in each of the cylinder positions; the moving disk is driven to rotate one revolution by the driving component, and the parallelism between the trajectory circle formed by the rotation trajectory of the first target ball and / or the second target ball and the absolute horizontal plane is measured by the laser positioning tracker.

7. The method for measuring the accuracy of a collimator in a radiotherapy device according to claim 6, characterized in that, The method for calculating the parallelism is as follows: Calculate the vertical distance between each sampling point on each of the trajectory circles and the absolute horizontal plane; The difference between the maximum and minimum vertical distances is used as the parallelism deviation. If the parallelism deviation is less than or equal to a preset threshold, then the installation of the secondary collimator is determined to meet the parallelism requirements.

8. The method for measuring the accuracy of a collimator in a radiotherapy device according to claim 6, characterized in that, The collimator accuracy measurement method also includes: Based on the parallelism measurement results, the position and angle of each of the cylinder positions are adjusted respectively; The coaxiality of each cylinder position with the central axis of the primary collimator is measured using the laser positioning and tracking instrument.

9. The method for measuring the accuracy of a collimator in a radiotherapy device according to claim 8, characterized in that, The coaxiality of each of the aforementioned cylinder positions with the central axis of the primary collimator is specifically measured as follows: The rotation trajectory of the first target ball forms a first trajectory circle, and the rotation trajectory of the second target ball forms a second trajectory circle. The center of the first trajectory circle and the center of the second trajectory circle are connected by a concentric axis. Calculate the distance and angular deviation between the concentric axis and the central axis of the primary collimator; Adjust the position of each cylinder according to the calculation results, so that the distance and angle deviation between the concentric axis and the central axis are within the preset threshold range.

10. The method for measuring the accuracy of a collimator in a radiotherapy device according to claim 6, characterized in that, The diameter of the circular surface formed by the rotation trajectory of the first target ball is d1, and the diameter of the circular surface formed by the rotation trajectory of the second target ball is d2. The collimator accuracy measurement method includes: The installation position deviation of each cylinder is determined by comparing the sizes of diameter d1 and diameter d2. By comparing the distances from diameters d1 and d2 to the central axis, it is determined whether the eccentricity between the primary collimator and the moving disk is within the preset tolerance range.

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