A scanning beam-limiting collimation mechanism for an X-ray source and a control method thereof

Abstract

The present invention relates to the field of X-ray photographing equipment, and in particular to a scanning beam limiting collimation mechanism of an X-ray source and a scanning control method thereof. The present invention adopts the following technical scheme: it includes a scanning collimation block, a scanning direction limiting block and a scanning drive device; the scanning collimation block is driven by the scanning drive device to move along the direction from the first scanning limit block to the second scanning limit block along the upper surface of the scanning direction limiting block. The advantage of the present invention is that it drives the scanning collimation block with a unit light field channel in the middle to move and scan along the upper surface of the scanning direction limiting block with an effective light field opening in the middle, and cooperates with the lateral limiting block at the same time, so that the scattered X-rays are shielded and absorbed by the scanning collimation block, the scanning direction limiting block and the lateral limiting block, thereby reducing the instantaneous radiation dose and the total radiation dose of the environment, protecting medical staff and the person being photographed, and improving the image quality.

Description

Technical Field

[0001] The present invention relates to the field of X-ray photographing equipment, and in particular to a scanning beam-limiting collimation mechanism of an X-ray source and a control method thereof. Background Art

[0002] During medical X-ray detection, conventional collimators adjust the size of the X-ray light field by adjusting the window size. The radiation dose and radiation dose rate in the environment are related to the X-ray exposure parameters, as well as the shielding performance of the collimator and the light field size. In particular, when the X-ray is emitted by the collimator, there are a large number of scattered rays in the X-ray beam, which are directly scattered into the environment, causing radiation pollution and affecting image quality. Summary of the invention

[0003] The object of the present invention is to provide a scanning beam-limiting collimation mechanism of an X-ray source and a control method thereof, which can reduce the instantaneous radiation dose and the total radiation dose of the environment, thereby protecting medical personnel and subjects and improving image quality.

[0004] To achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a scanning beam-limiting collimation mechanism of an X-ray source, comprising a scanning collimation block, a scanning direction limiting block and a scanning drive device, the scanning collimation block comprising a first collimation block and a second collimation block, the scanning direction limiting block comprising a first scanning direction limiting block and a second scanning direction limiting block, the first collimation block and the second collimation block are separated to form a unit light field channel, and the first scanning direction limiting block and the second scanning direction limiting block are separated to form an effective light field opening; the scanning collimation block is driven by the scanning drive device to move along the direction from the first scanning limiting block toward the second scanning limiting block, close to the upper surface of the scanning direction limiting block.

[0005] Furthermore, a lateral limiting block is arranged between the first collimation block and the second collimation block, and the lateral limiting block includes a first lateral limiting block and a second lateral limiting block, and the first lateral limiting block and the second lateral limiting block are movably arranged at the front and rear ends of the first collimation block and the second collimation block respectively.

[0006] Furthermore, a starting point proximity switch is provided on the first scanning direction limiting block, and an end point proximity switch is provided on the second scanning direction limiting block. A first trigger piece corresponding to the starting point proximity switch is provided at the bottom of the first collimation block near the edge of the second collimation block, and a second trigger piece corresponding to the end point proximity switch is provided at the bottom of the second collimation block near the edge of the first collimation block.

[0007] Furthermore, a first buffer zone is formed between the starting point proximity switch and the edge of the first scanning direction limiting block close to the second scanning direction limiting block, and a second buffer zone is formed between the end point proximity switch and the edge of the second scanning direction limiting block close to the first scanning direction limiting block. The widths of the first buffer zone and the second buffer zone are both greater than the width between the bottom of the first alignment block and the second alignment block.

[0008] Furthermore, the cross-sections of the first collimation block, the second collimation block, the first scanning direction limiting block and the second scanning direction limiting block are all fan-shaped with the focus of the X-ray tube as the center, and the scanning drive device drives the first collimation block and the second collimation block to make circular motion with the focus of the X-ray tube as the center along the upper surfaces of the first scanning direction limiting block and the second scanning direction limiting block.

[0009] Preferably, a gap is provided between the bottom of the scanning collimation block and the upper surface of the scanning direction limiting block; and a gap is provided between the lateral limiting block and the scanning collimation block.

[0010] A scanning control method of a scanning beam limiting collimation mechanism of an X-ray source comprises the following steps:

[0011] S01. Set the running speed of the scanning collimation block according to the exposure parameters of the X-ray source.

[0012] S02. Trigger the command to start scanning, so that the scanning alignment block runs at the set running speed.

[0013] S03. Control the X-ray tube to start exposure before the unit light field channel between the first scanning collimation block and the second scanning collimation block enters the effective light field opening between the first scanning direction limiting block and the second scanning direction limiting block, and the X-ray tube ends exposure after the unit light field channel leaves the effective light field opening.

[0014] S04. After the unit light field channel leaves the effective light field opening, the scanning collimation block stops scanning and resets.

[0015] Specifically, in step S01, the running speed of the scanning collimation block is calculated according to the formula: scanning speed = unit light field width / irradiation time, and the irradiation time is calculated according to the formula: irradiation time = target current time product / X-ray source tube current.

[0016] Furthermore, in step S03, before the unit light field channel enters the effective light field opening, the first trigger plate at the bottom of the first collimation block triggers the first scan to approach the starting point switch on the limiting block and thereby controls the X-ray tube to start exposure; after the unit light field channel leaves the effective light field opening, the second trigger plate at the bottom of the second collimation block triggers the second scan to approach the end point switch on the limiting block and thereby controls the X-ray tube to end exposure.

[0017] Furthermore, when the scanning collimation block is reset, the first trigger sheet on the first collimation block triggers the first scanning to approach the starting point on the limiting block and then stops after a delay.

[0018] The advantages of the present invention are as follows: by driving the scanning collimation block with a unit light field channel in the middle to move and scan along the upper surface of the scanning direction limiting block with an effective light field opening in the middle, and cooperating with the lateral limiting block, the X-rays can only be emitted from the unit light field channel in the middle of the scanning collimation block and scan along the effective light field opening, so that the remaining scattered X-rays are shielded and absorbed by the scanning collimation block, the scanning direction limiting block and the lateral limiting block, thereby reducing the environmental instantaneous radiation dose and the total radiation dose, protecting medical staff and the person being photographed, and improving the image quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Attached Figure 1 is an overall structural diagram of the beam limiting and collimating mechanism in the embodiment;

[0020] Attached Figure 2 is a cross-sectional view of a beam limiting and collimating mechanism in an embodiment;

[0021] Attached Figure 3 It is an exposure expansion diagram of the shooting process of the beam limiting collimation mechanism in the embodiment;

[0022] Attached Figure 4 Flow chart of the control method of the beam limiting and collimating mechanism in the embodiment. DETAILED DESCRIPTION

[0023] Example 1: Reference Figure 1-3 A scanning beam limiting collimation mechanism of an X-ray source comprises a scanning collimation block 1, a scanning direction limiting block 2 and a scanning drive device 3, wherein the scanning collimation block 1 comprises a first collimation block 11 and a second collimation block 12, the scanning direction limiting block 2 comprises a first scanning direction limiting block 21 and a second scanning direction limiting block 22, the first collimation block 11 and the second collimation block 12 are spaced apart to form a unit light field channel 13, and the first scanning direction limiting block 21 and the second scanning direction limiting block 22 are spaced apart to form an effective light field opening 23; the scanning collimation block 1 is driven by the scanning drive device 3 to move along the direction of the first scanning limiting block 21 toward the second scanning limiting block 22, close to the upper surface of the scanning direction limiting block 2.

[0024] In this embodiment, the scanning collimation block 1 is used to limit the beam of the X-rays emitted from the X-ray tube, so that the X-rays emitted from the X-ray tube can only pass through the unit light field channel 13 between the first collimation block 11 and the second collimation block 12, and the others will be shielded and absorbed by the first collimation block 11 and the second collimation block 12. When the scanning collimation block 1 is moved for scanning, the X-rays emitted by the X-ray tube will move with the movement of the unit light field channel 13 of the scanning collimation block, and the scanning collimation block 1 moves along the upper surface of the scanning direction limiting block 2, so that the unit light field channel 13 can move along the first scanning direction limiting block 21 and the second scanning direction limiting block 22. The effective light field opening 23 between the blocks 22 is moved and scanned, so that the X-rays emitted by the X-ray tube can be scanned and detected along the effective light field opening 23 with the width of the unit light field channel 13, so as to meet the area required for shooting; since the actual width of the X-ray emission is only the width of the unit light field channel 13, the smaller the width, the easier it is to control, which can reduce the instantaneous radiation dose of the X-rays in the environment; and the scanning collimation block 1 and the scanning direction limiting block 2 can effectively suppress the X-rays scattered into the environment when the X-ray tube is exposed, reduce the total radiation dose in the environment, thereby protecting medical staff and the person being photographed, and improving image quality. Among them, the first scanning direction limiting block 21 and the second scanning direction limiting block 22 can be moved left and right along the scanning direction of the scanning collimation block 1, so that the width of the effective light field opening 23 can be adjusted as needed, that is, the range of the X-ray scanning can be adjusted.

[0025] A transverse limiting block 4 is also arranged between the first collimating block 11 and the second collimating block 12. The transverse limiting block 4 includes a first transverse limiting block 41 and a second transverse limiting block 42. The first transverse limiting block 41 and the second transverse limiting block 42 are movably arranged at the front and rear ends of the first collimating block 11 and the second collimating block 12, respectively. The transverse limiting block 4 limits the front and rear ends of the unit light field channel between the first collimating block 11 and the second collimating block 12, thereby further limiting the length of the unit light field channel 13. The first transverse limiting block 41 and the second transverse limiting block 42 can move forward and backward along the unit light field channel 13 between the first collimating block 11 and the second collimating block 12, thereby adjusting the length of the unit light field channel 13, thereby adjusting the overall area of ​​the X-ray scanning. The scanning collimating block 1, the scanning direction limiting block 2 and the transverse limiting block 4 are all made of materials with good X-ray shielding and absorption properties, such as aluminum blocks or lead blocks.

[0026] Specifically, the cross-sections of the first collimation block 11, the second collimation block 12, the first scanning direction limiting block 21 and the second scanning direction limiting block 22 are all fan-shaped with the focus P of the X-ray tube as the center, and the scanning drive device 3 drives the first collimation block 11 and the second collimation block 12 to make circular motion along the upper surfaces of the first scanning direction limiting block 21 and the second scanning direction limiting block 22 with the focus P of the X-ray tube as the center.

[0027] Furthermore, a starting point proximity switch 211 is provided on the first scanning direction limiting block 21, and an end point proximity switch 221 is provided on the second scanning direction limiting block 22. A first trigger piece 111 corresponding to the starting point proximity switch 211 is provided at the bottom of the first collimation block 11 near the edge of the second collimation block 12, and a second trigger piece 121 corresponding to the end point proximity switch 221 is provided at the bottom of the second collimation block 12 near the edge of the first collimation block 11.

[0028] In a further embodiment, by setting corresponding starting point proximity switches 211, first trigger pieces 111, end point proximity switches 221, and second trigger pieces 121 on the scanning direction limiting block 2 and the scanning collimation block 1, the relative position of the unit light field channel 13 of the scanning collimation block in the effective light field opening 23 of the scanning direction limiting block 2 is detected, and the X-ray tube and the scanning drive device 3 can be controlled; specifically, the starting point proximity switch 211 is set on the first scanning direction limiting block 21, the first trigger piece 111 is set at the bottom of the first collimation block 11 near the edge of the second collimation block 12, the end point proximity switch 221 is set on the second scanning direction limiting block 22, and the second trigger piece 121 is set at the bottom of the second collimation block 12 near the edge of the first collimation block 11; when the scanning collimation block 1 is driven by the scanning drive device 3 to move from the first scanning direction limiting block 21 to the second scanning direction limiting block 22, that is, to move along the scanning direction, the first collimation block 1 When the first trigger piece 111 at the bottom of 11 reaches above the starting point proximity switch 211, the starting point proximity switch 211 is triggered, and the X-ray tube is controlled to start exposure. Then the scanning drive device 3 continues to drive the scanning collimation block 1 to move along the scanning direction, so that the unit light field channel 13 passes through the effective light field opening 23 for scanning detection. When the second trigger piece 121 at the bottom of the second collimation block 12 reaches above the end point proximity switch 221, the end point contact switch 221 is triggered, and the X-ray tube is controlled to end exposure. At the same time, the scanning drive device 3 is controlled to stop driving and move in the opposite direction of the scanning direction, that is, the reset direction. During the reset process, when the first trigger piece 111 of the first collimation block 11 reaches above the starting point proximity switch 211, the starting point proximity switch 211 is triggered, and the scanning drive device 3 is delayed to stop driving the scanning collimation block 1 to move. The delay time can be determined according to the speed at which the scanning drive device 3 drives the scanning collimation block 1, which is generally a few tenths of a second. At the same time, in order to prevent the first triggering piece 111 and the second triggering piece 121 from causing confusion with the triggering of the starting point proximity switch 211 and the end point proximity switch 221, the first triggering piece 111 and the starting point proximity switch 211 and the second triggering piece 121 and the end point proximity switch 221 can be staggered, that is, the first triggering piece 111 and the starting point proximity switch 211 and the second triggering piece 121 and the end point proximity switch 221 are located in different vertical planes, so that the second triggering piece 121 will not mistakenly trigger the starting point proximity switch 211, and the first triggering piece 111 will not mistakenly trigger the end point proximity switch 221. Among them, the starting point proximity switch 211 and the end point proximity switch 221 can adopt Hall proximity switches, and correspondingly, the first triggering piece 111 and the second triggering piece 121 are magnetic materials.

[0029] Specifically, a first buffer zone 241 is formed between the starting point proximity switch 211 and the edge of the first scanning direction limiting block 21 close to the second scanning direction limiting block 22, and a second buffer zone 242 is formed between the end point proximity switch 221 and the edge of the second scanning direction limiting block 22 close to the first scanning direction limiting block 21. The widths of the first buffer zone 241 and the second buffer zone 242 are both greater than the width of the unit light field channel 13 between the bottom of the first collimation block 11 and the bottom of the second collimation block 12. The first buffer zone 241 and the second buffer zone 242 are used to ensure that the X-ray tube has sufficient pre-exposure time when the unit light field channel 13 enters and leaves the effective light field opening 23. Since the widths of the first buffer zone 241 and the second buffer zone 242 are both greater than the width of the unit light field channel 13, before the unit light field channel 13 enters the effective light field opening 23, the first trigger plate 111 has triggered the starting point proximity switch 211, so that the X-ray tube starts to be exposed, thereby ensuring that when the unit light field channel 13 enters the effective light field opening 23, the X-ray tube can emit stable and effective X-rays. After the unit light field channel 13 leaves the effective light field opening 23, the second trigger plate 121 will trigger the end point proximity switch 221, so that the X-ray tube ends the exposure, thereby ensuring that when the unit light field channel 13 leaves the effective light field opening 23, the X-ray tube can still emit stable and effective X-rays, thereby ensuring that the irradiation intensity in the effective light field opening 23 is uniform, thereby improving the detection effectiveness.

[0030] Reference Figure 4 At the same time, the present application also provides a scanning control method of a scanning beam limiting collimation mechanism of an X-ray source, comprising the following steps:

[0031] S01. Set the running speed of the scanning collimation block according to the exposure parameters of the X-ray source.

[0032] S02. Trigger the command to start scanning, so that the scanning alignment block 1 runs at the set running speed.

[0033] S03. Control the X-ray tube to start exposure before the unit light field channel 13 between the first collimation block 11 and the second collimation block 12 enters the effective light field opening 23 between the first scanning direction limiting block 21 and the second scanning direction limiting block 22, and the X-ray tube ends exposure after the unit light field channel 13 leaves the effective light field opening 23.

[0034] S04. After the unit light field channel 13 leaves the effective light field opening 23, the scanning collimation block 1 stops scanning and resets.

[0035] Specifically, in step S01, the running speed of the scanning collimation block is calculated according to the formula: scanning speed = unit light field width / irradiation time, wherein the irradiation time is calculated according to the formula: irradiation time = target current time product / X-ray source tube current, wherein the target current time product reflects the irradiation intensity of the target, and the value can be set according to actual needs, and the X-ray tube current is a parameter of the X-ray source, which is set according to specific requirements.

[0036] Specifically, in step S03, before the unit light field channel 13 enters the effective light field opening 23, the first trigger plate 111 at the bottom of the first collimation block 11 triggers the first scan to approach the starting point switch 211 on the limiting block 21 and thereby controls the X-ray tube to start exposure; after the unit light field channel 13 leaves the effective light field opening 23, the second trigger plate 121 at the bottom of the second collimation block 12 triggers the second scan to approach the end point switch 221 on the limiting block 22 and thereby controls the X-ray tube to end exposure.

[0037] Specifically, when the scanning collimation block 1 is reset in step S04, the first trigger piece 111 on the first collimation block 11 triggers the first scanning to the starting point on the limiting block 21 and then stops after a delay.

[0038] Of course, the above are only preferred embodiments of the present invention, and are not intended to limit the scope of use of the present invention. Therefore, any equivalent changes made to the principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A scanning beam-limiting collimation mechanism for an X-ray source, characterized in that: The scanning collimator comprises a scanning direction limiting block, a scanning direction limiting block and a scanning driving device, wherein the scanning collimator comprises a first collimator block and a second collimator block, the scanning direction limiting block comprises a first scanning direction limiting block and a second scanning direction limiting block, the first collimator block and the second collimator block are separated to form a unit light field channel, and the first scanning direction limiting block and the second scanning direction limiting block are separated to form an effective light field opening; the scanning collimator block is driven by the scanning driving device to move along the direction from the first scanning limiting block to the second scanning limiting block, close to the upper surface of the scanning direction limiting block; a lateral limiting block is arranged between the first collimator block and the second collimator block, and the lateral limiting block comprises a first lateral A limiting block and a second lateral limiting block, the first lateral limiting block and the second lateral limiting block are movably arranged at the front and rear ends of the first collimation block and the second collimation block respectively; a starting point proximity switch is arranged on the first scanning direction limiting block, and an end point proximity switch is arranged on the second scanning direction limiting block; a first trigger piece corresponding to the starting point proximity switch is arranged at the edge of the bottom of the first collimation block close to the edge of the second collimation block, and a second trigger piece corresponding to the end point proximity switch is arranged at the edge of the bottom of the second collimation block close to the first collimation block; the starting point proximity switch and the end point proximity switch adopt Hall proximity switches, and the first trigger piece and the second trigger piece are magnetic materials respectively.

2. The scanning beam-limiting collimation mechanism of an X-ray source according to claim 1, characterized in that: A first buffer zone is formed between the starting point proximity switch and the edge of the first scanning direction limiting block close to the second scanning direction limiting block, and a second buffer zone is formed between the end point proximity switch and the edge of the second scanning direction limiting block close to the first scanning direction limiting block. The widths of the first buffer zone and the second buffer zone are both greater than the width between the bottoms of the first alignment block and the second alignment block.

3. The scanning beam limiting collimation mechanism of an X-ray source according to claim 1 or 2, characterized in that: The cross-sections of the first collimation block, the second collimation block, the first scanning direction limiting block and the second scanning direction limiting block are all fan-shaped with the focus of the X-ray tube as the center. The scanning drive device drives the first collimation block and the second collimation block to make circular motion along the upper surfaces of the first scanning direction limiting block and the second scanning direction limiting block with the focus of the X-ray tube as the center.

4. A scanning control method for a scanning beam limiting collimation mechanism of an X-ray source as claimed in any one of claims 1 to 3, characterized in that The steps include: S01. Setting the running speed of the scanning collimation block according to the exposure parameters of the X-ray source; S02. Trigger the command to start scanning, so that the scanning alignment block runs at the set running speed; S03. Control the X-ray tube to start exposure before the unit light field channel between the first scanning collimation block and the second scanning collimation block enters the effective light field opening between the first scanning direction limiting block and the second scanning direction limiting block, and the X-ray tube ends exposure after the unit light field channel leaves the effective light field opening; S04. After the unit light field channel leaves the effective light field opening, the scanning collimation block stops scanning and resets.

5. The scanning control method of the scanning beam limiting collimation mechanism of an X-ray source according to claim 4, characterized in that: In the step S01, the running speed of the scanning collimation block is calculated according to the formula: scanning speed=unit light field width / irradiation time, and the irradiation time is calculated according to the formula: irradiation time=target current-time product / X-ray source tube current.

6. The scanning control method of the scanning beam limiting collimation mechanism of an X-ray source according to claim 4, characterized in that: In step S03, before the unit light field channel enters the effective light field opening, the first trigger plate at the bottom of the first collimation block triggers the first scan to approach the starting point switch on the limiting block and thereby controls the X-ray tube to start exposure; after the unit light field channel leaves the effective light field opening, the second trigger plate at the bottom of the second collimation block triggers the second scan to approach the end point switch on the limiting block and thereby controls the X-ray tube to end exposure.

7. The scanning control method of the scanning beam limiting collimation mechanism of an X-ray source according to claim 6, characterized in that: When the scanning collimation block is reset, the first trigger piece on the first collimation block triggers the first scanning to approach the starting point on the limiting block and then stops after a delay.

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