Shutter device for radiation source, radiation beam emitting device and radiation inspection system

Abstract

The utility model relates to a shutter device, a radiation beam emitting device and a radiation inspection system. The shutter device comprises: a baffle, which is made of a material suitable for shielding the radiation beam and is provided with a slit; a rotating device, which is used to rotate the baffle to a predetermined angle position, and the predetermined angle position includes at least a first angle position and a second angle position; when the baffle is rotated to the first angle position, the radiation beam emitted by the radiation source cannot pass through the slit to enter the detection area; when the baffle is rotated to the second angle position, the radiation beam can pass through the slit to enter the detection area. Thus, the shutter device can provide support for the radiation source to quickly emit a stable radiation beam to the detection area.

Description

Technical Field

[0001] The utility model relates to the field of radiation imaging, in particular to a shutter device for a radiation source, a radiation beam emitting device and a radiation inspection system. Background Art

[0002] In a radiation imaging system, it is necessary to control the emission (beam emission) and stop (beam stop) of the radiation beam to start and stop the radiation scan. Machine radiation sources including X-ray sources and electron accelerators are widely used in the field of radiation imaging. The radiation source emits X-ray radiation when powered on and no longer emits radiation after the power supply is cut off. By controlling the power on and off of the radiation source, it is very convenient to control its beam emission and beam stop.

[0003] Taking X-ray sources and electron accelerators as examples, the radiation sources they generate have a certain rise and stabilization time after power-on, which is usually in the order of seconds (the shortest takes about 1 second). The radiation scanning imaging quality during this period is poor or even impossible. For fast inspection equipment for moving targets, it is usually necessary to avoid personnel areas such as the cab and quickly start the radiation source to start scanning. If the radiation source starts for a long time, it will make it impossible to effectively inspect the corresponding scanning area.

[0004] The faster the moving target moves, the longer the radiation source takes to start stabilizing, resulting in a longer area of ​​missed scanning or poor scanning quality. For example, if the moving target moves at a speed of 5m / s, and the radiation source starts up for 1 second, the initial 5m / s*1s=5m long range cannot be effectively inspected (such as the fast-pass passenger car trunk inspection application, where the length of the trunk in the inspection area is only 1m to 1.5m). Therefore, in similar fast-pass passenger car trunk inspection application scenarios, the radiation source needs to be able to quickly emit a stable radiation beam after receiving the radiation beam emission command. Utility Model Content

[0005] A technical problem to be solved by the utility model is how to enable a radiation source to quickly emit a stable radiation beam.

[0006] According to the first aspect of the utility model, a shutter device for a radiation source is provided, comprising: a baffle, the baffle being made of a material suitable for shielding a radiation beam, and a slit being provided in the baffle; a rotating device, for rotating the baffle to a predetermined angular position, the predetermined angular position comprising at least a first angular position and a second angular position; when the baffle is rotated to the first angular position, the radiation beam emitted by the radiation source cannot pass through the slit to enter the detection area; when the baffle is rotated to the second angular position, the radiation beam can pass through the slit to enter the detection area.

[0007] Optionally, the baffle includes a baffle block with a slit in the middle of the baffle block; or the baffle includes two baffle blocks, and a gap formed between the two baffle blocks is the slit.

[0008] Optionally, when the baffle is rotated to a first angular position, the size of the baffle in the radiation beam width direction is greater than the radiation beam width at the baffle position; when the baffle is rotated to a second angular position, the size of the slit in the radiation beam width direction is greater than the radiation beam width at the slit position.

[0009] Optionally, the rotating device rotates the baffle from a first angle position to a second angle position, the first angle is not greater than 90 degrees, the slits include at least a first slit, and when the baffle is rotated to the second angle position, the width direction of the first slit is consistent or substantially consistent with the width direction of the radiation beam, and the angle between the center line of the first slit and the thickness direction of the baffle is the first angle.

[0010] Optionally, the predetermined angle position also includes a third angle position, and the rotating device continues to rotate the baffle from the first angle position through the second angle position to the third angle position by the second angle, the second angle is not greater than 90 degrees minus the first angle, and the slit also includes a second slit, and when the baffle is rotated to the third angle position, the width direction of the second slit is consistent or substantially consistent with the width direction of the radiation beam, and when the baffle is rotated to any angle position between the second angle position and the third angle position, the radiation beam can pass through the slit area covered by the combination of the first slit and the second slit.

[0011] Optionally, the width of the first slit is the same as the width of the second slit, and the angle between the center line of the first slit and the center line of the second slit is a second angle.

[0012] Optionally, an attenuation module for attenuating the radiation beam is provided in the slit, and when the baffle is rotated to different angular positions between the second angular position and the third angular position, the radiation beam can be incident from the slit area to the detection area via attenuation modules of different thicknesses.

[0013] Optionally, the first angle is greater than or equal to 30 degrees and less than or equal to 60 degrees.

[0014] Optionally, the shutter device also includes: an angle position sensor for detecting the angle position of the baffle and sending the detected angle position to the control device; the rotating device receives the instruction sent by the control device, and rotates a predetermined angle according to the instruction to rotate the baffle to a desired angle position.

[0015] According to a second aspect of the present invention, there is also provided a radiation beam emitting device, comprising: a radiation source for emitting a radiation beam to a detection area; and the shutter device mentioned in the first aspect above.

[0016] According to the third aspect of the utility model, a radiation inspection system is also provided, comprising: the radiation beam emitting device mentioned in the second aspect above; one or more detectors, arranged at predetermined positions in the radiation inspection channel, for receiving imaging radiation beams transmitted or scattered from the inspected object in the inspection area; a control device, for sending a first instruction to the radiation beam emitting device in response to the part to be inspected of the inspected object arriving or about to arrive at the inspection area, and the radiation beam emitting device rotates the baffle from the first angular position to the second angular position in response to the first instruction.

[0017] Optionally, the control device further sends a second instruction to the radiation beam emitting device in response to the end of the part to be inspected leaving or about to leave the detection area, and the radiation beam emitting device rotates the baffle from the second angular position to the first angular position in response to the second instruction.

[0018] Optionally, the control device also sends a third instruction to the radiation beam emitting device according to the moving speed of the inspected object, and the radiation beam emitting device continues to rotate the baffle by a third angle in response to the third instruction so that the radiation beam is incident on the detection area through an attenuation module of a predetermined thickness in the slit, wherein the predetermined thickness is negatively correlated with the moving speed.

[0019] Optionally, the control device further sends a fourth instruction to the radiation beam emitting device in response to the front end of the part to be inspected of the inspected object being a predetermined distance away from the detection area, and the radiation beam emitting device starts the radiation source in response to the fourth instruction.

[0020] The shutter device in the utility model at least includes a baffle and a rotating device, the rotating device is used to rotate the baffle to a predetermined angle position, the predetermined angle position includes at least a first angle position and a second angle position; when the baffle is rotated to the first angle position, the radiation beam emitted by the radiation source cannot pass through the slit to enter the detection area; when the baffle is rotated to the second angle position, the radiation beam can pass through the slit to enter the detection area. Therefore, the shutter device of the utility model can provide support for the radiation source to quickly emit a stable radiation beam. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and other objects, features and advantages of the present invention will become more apparent through a more detailed description of exemplary embodiments of the present invention in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments of the present invention.

[0022] Figure 1 It is a schematic block diagram showing the basic structure of a radiation beam emitting device according to an embodiment of the utility model.

[0023] Figure 2A Schematic diagram showing the structure of a slit according to an embodiment of the utility model.

[0024] Figure 2B It is shown that Figure 2A Schematic diagrams of the corresponding shutter device in the open state and the closed state respectively.

[0025] Figure 2C Schematic diagram showing the structure of a slit according to another embodiment of the utility model.

[0026] Figure 2D Schematic diagram showing the structure of a slit according to another embodiment of the utility model.

[0027] Figure 2E is shown with Figure 2D Schematic diagram of the corresponding shutter device in different states.

[0028] Figure 2F The figure is a schematic diagram showing the working principle of a shutter device according to an embodiment of the utility model.

[0029] Figure 3A It is a schematic diagram showing a radiation beam emitting device in an open shutter state according to an embodiment of the utility model.

[0030] Figure 3B It is a schematic diagram showing a radiation beam emitting device in a shutter closed state according to an embodiment of the utility model.

[0031] Figure 3C It is a schematic structural diagram showing a shutter device according to an embodiment of the utility model.

[0032] Figure 4A , Figure 4B Schematic diagrams showing the radiation beam emitting device in a shutter closed state at different viewing angles.

[0033] Figure 5A , Figure 5B Schematic diagrams showing the radiation beam emitting device in an open state at different viewing angles.

[0034] Figure 6 It is a schematic block diagram showing the basic structure of a radiation inspection system according to an embodiment of the present invention.

[0035] Figure 7 It is a schematic structural diagram showing a radiation inspection system according to another embodiment of the utility model.

[0036] Fig. 8A is a schematic diagram showing a radiation inspection system in a shutter open state according to another embodiment of the utility model.

[0037] Figure 8Bis a schematic diagram showing a radiation inspection system in a shutter closed state according to another embodiment of the utility model DETAILED DESCRIPTION

[0038] The preferred embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the preferred embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0039] Those skilled in the art should understand that the terms "first", "second", etc. in the present invention are used to distinguish similar objects, rather than to describe a specific order or sequence, and have no additional limiting effect.

[0040] It takes a certain amount of time for the radiation source to start up and emit a stable radiation beam. The longer the time it takes for the radiation source to start up and emit a stable radiation beam, the worse the scanning inspection effect will be, or even the scanning inspection cannot be completed.

[0041] The utility model proposes to start the radiation source in advance to obtain a stable radiation beam, and control the opening and closing of the emission path of the radiation beam through a shutter device, so that the radiation source can quickly emit a stable radiation beam after receiving a radiation beam emission instruction.

[0042] Figure 1 It is a schematic block diagram showing the basic structure of a radiation beam emitting device according to an embodiment of the utility model.

[0043] See also Figure 1 The radiation beam emitting device 1 may include a radiation source 10 and a shutter device 20 .

[0044] The radiation source 10 is used to emit a radiation beam for imaging to a detection area.

[0045] The radiation beam may be a gamma ray, an X-ray, a neutron, a proton, etc.; accordingly, the radiation source 10 may be a radioactive isotope, an electron accelerator, an X-ray machine, a neutron generator, a proton generator, etc.

[0046] In addition to the core part for radiation emission (such as the accelerating tube of an electron linear accelerator, the radiation head of an electron beta accelerator, and the X-ray tube of an X-ray machine), the radiation source 10 may also include peripheral auxiliary power supply, cooling and other components. For example, the radiation source 10 may include a radiation source shielding device and a primary collimator. The radiation generated by the radiation source 10 may be collimated by the radiation source shielding device and the primary collimator to preliminarily form a radiation beam of a predetermined shape required for radiation inspection.

[0047] The shutter device 20 is disposed on the radiation beam path. The shutter device may include at least a baffle 100 and a rotating device 200.

[0048] The baffle 100 is made of a material suitable for shielding the radiation beam. Taking the radiation beam as X-rays or gamma rays as an example, the baffle 100 can be made of, but not limited to, heavy metal materials such as steel, lead, and tungsten; or, the baffle 100 can also be made of alloys or composite materials containing these heavy metal materials.

[0049] The baffle 100 is provided with a slit that allows the radiation beam to pass through. The radiation beam passing through the slit position has a certain width. The width of the slit may be greater than or equal to the width of the radiation beam passing through the slit position, and may be less than the width of the baffle 100.

[0050] The baffle 100 may include a block, and a slit may be provided in the middle of the block. The baffle 100 may also include two blocks, and the gap (i.e., the gap) formed between the two blocks is the slit. That is, the baffle 100 may be composed of one block or two blocks. The block may be, but is not limited to, a rectangular block.

[0051] The rotating device 200 may be, but is not limited to, a rotating electromagnet. The rotating device 200 can rotate the baffle 100 to place the baffle at different angles, thereby changing the position of the slit. In the case where the baffle 100 is composed of two blocks, the rotating device 200 can rotate the two blocks as a whole to change the position of the slit. Alternatively, the rotating device 200 can also rotate the two blocks independently to change the position of the slit.

[0052] The rotating device 200 can rotate the baffle to a predetermined angle position. The predetermined angle position can include at least a first angle position and a second angle position. When the baffle 100 is rotated to the first angle position, the shutter device is in a closed state, and the radiation beam emitted by the radiation source is blocked by the baffle 100 and cannot pass through the slit to enter the detection area. Conversely, when the baffle 100 is rotated to the second angle position, the shutter device is in an open state, and the radiation beam is not blocked by the baffle 100 and can pass through the slit to enter the detection area.

[0053] When the baffle 100 is rotated to the first angular position, the size of the baffle 100 in the radiation beam width direction is greater than the radiation beam width at the baffle position. When the baffle 100 is rotated to the second angular position, the size of the slit in the radiation beam width direction is greater than the radiation beam width at the slit position. The width of the baffle 100 may refer to the size of the baffle 100 in the radiation beam width direction when the baffle 100 is rotated to the first angular position. The thickness of the baffle 100 may refer to the size of the baffle 100 in the propagation direction of the radiation beam when the baffle 100 is rotated to the first angular position. The thickness of the baffle 100 may be greater than the width of the baffle 100. For example, the baffle 100 may be a cuboid baffle with a relatively small width and a relatively large thickness.

[0054] Based on the radiation beam emitting device of the present invention, the radiation source 10 can be started in advance to obtain a stable radiation beam. By controlling the rotating device 200 to rotate the baffle 100 to a suitable angular position (such as a first angular position or a second angular position), the need to emit or stop the radiation beam during the radiation inspection process can be met.

[0055] For example, before the part of the object to be inspected (such as the trunk of a vehicle) enters the detection area, the radiation source 10 can be started to obtain a stable radiation beam. At this time, the rotating device 200 can be controlled to rotate the baffle to the first angle position, and the radiation beam emitted by the radiation source 10 cannot enter the detection area through the slit. When the part of the object to be inspected reaches or is about to reach the detection area, the rotating device 200 can be controlled to rotate the baffle 100 to the second angle position, so that the radiation beam emitted by the radiation source 10 can enter the detection area through the slit, and then the radiation inspection of the part to be inspected can be achieved. When the part of the object to be inspected (such as the trunk of a vehicle) leaves or is about to leave the detection area, the rotating device 200 can be controlled to rotate the baffle 100 to the first angle position, so that the radiation beam emitted by the radiation source 10 will not be incident on the detection area through the slit, so that the radiation inspection of the detection area can be stopped.

[0056] The shutter device can be arranged between the radiation source 10 and the inspected object. Preferably, the shutter device (i.e., the baffle 100 and the rotating device 200) should be arranged as close to the radiation source 10 as possible, so as to minimize the size and weight of the baffle, reduce the rotational inertia of the shutter device, and thus improve the response speed of the shutter opening / closing.

[0057] In order to quickly open the shutter, when the shutter is closed (i.e., the baffle is rotated to the first angle position), the width of the baffle 100 can be as narrow as possible while ensuring that it is greater than the width of the radiation beam here, so as to minimize the rotational inertia of the shutter device. For example, in one embodiment, the width of the radiation beam at the position of the baffle 100 is about 2 mm. Taking into account the shielding and installation errors, the width of the baffle 100 can be set to 5 mm. Correspondingly, the width of the slit can typically be set to 3.5 mm. The thickness of the baffle 100 should be sufficient to shield the radiation beam. For example, the thickness of the baffle 100 should be such that the dose rate of the radiation beam incident on the detection area is not greater than a predetermined threshold when the shutter is in a closed state. The predetermined threshold can be set according to actual conditions, such as 40 μSv / h. Preferably, the predetermined threshold can be 2.5 μSv / h.

[0058] Using a rotating device 200 with a higher rotation speed can improve the response speed of shutter opening / closing.

[0059] When the same rotating device 200 is used, reducing the rotation angle required for the shutter device to rotate from closed to open (i.e., rotating from the first angle position to the second angle position) can increase the response speed of the shutter from closed to open. FIG. 2A to FIG. 2F An exemplary description is given of how to reduce the rotation angle required for the shutter device to rotate from closed to open.

[0060] Figure 2A Schematic diagram showing the structure of a slit according to an embodiment of the utility model.

[0061] Figure 2B is shown with Figure 2A Schematic diagrams of the corresponding shutter device in the open state and the closed state respectively.

[0062] See also Figure 2A The center line of the slit 103 is usually at an angle of 90 degrees to the thickness direction of the baffle 100. The center line of the slit 103 refers to the straight line where the center of the slit 103 is located, that is, the central axis of the slit 103. The center line of the slit 103 is parallel to the length direction of the slit 103, and can be understood as a straight line connecting the midpoints of the slit 103 in the length direction.

[0063] Figure 2B The left view in the middle is a schematic diagram of the state when the baffle 100 is rotated to the first angle position, that is, a schematic diagram of the shutter device being in a closed state. Figure 2B The view on the right side of the middle is a schematic diagram of the state when the baffle 100 is rotated to the second angle position, that is, a schematic diagram of the shutter device being in the open state.

[0064] See also Figure 2BThe minimum rotation angle required to rotate the baffle 100 from the first angle position to the second angle position is close to 90 degrees. That is, the baffle 100 needs to be rotated nearly 90 degrees before the shutter device can be switched from the closed state to the open state.

[0065] In order to reduce the rotation angle required to rotate the baffle 100 from a first angular position that completely blocks the radiation beam to a second angular position where the radiation beam can completely pass through the slit 103, thereby increasing the response speed of the shutter from closing to opening, the utility model proposes that the slit 103 can be designed so that the angle between the center line and the thickness direction of the baffle 100 is less than 90 degrees.

[0066] Figure 2C Schematic diagram showing the structure of a slit according to another embodiment of the utility model.

[0067] See also Figure 2C , the angle between the center line of the slit 103 and the thickness direction of the baffle 100 can be recorded as α. The minimum rotation angle required to rotate the baffle 100 from the first angle position to the second angle position (i.e., the first angle described below) is the angle α, and α is not greater than 90 degrees. The smaller α is, the faster the shutter responds from closed to open, but at the same time the thickness of the baffle 100 will become smaller, making the shielding ability of the baffle 100 to the radiation beam weaker when the shutter is in the closed state. Therefore, the value of α can be set according to actual conditions. Exemplarily, α can be set to an acute angle less than 90 degrees. For example, α can be greater than or equal to 30 degrees and less than or equal to 60 degrees.

[0068] and Figure 2A The center line of the slit 103 shown usually forms an angle of 90 degrees with the thickness direction of the baffle 100. By setting the center line of the slit 103 to form an angle less than 90 degrees with the thickness direction of the baffle 100, the rotation angle required for the shutter device to change from closed to open can be reduced, thereby improving the response speed of the shutter from closed to open.

[0069] For example, a rectangular block that does not originally have a slit 103 can be cut to obtain a baffle 100 having a slit 103. There are many specific cutting methods. For example, see FIG. 2A to FIG. 2C As shown, the slit 103 with a predetermined width can be obtained by cutting along a certain angle (not greater than 90 degrees) with the thickness direction of the rectangular block. Different slit positions in the slit 103 can have the same slit width.

[0070] Figure 2D Schematic diagram showing the structure of a slit according to another embodiment of the utility model.

[0071] See also Figure 2D, the slit 103 may include a first slit 103-1 and a second slit 103-2. The slit 103 may be considered to be composed of the first slit 103-1 and the second slit 103-2. The first slit 103-1 and the second slit 103-2 have a partially overlapping slit area, and the slit area covered by the combination of the first slit 103-1 and the second slit 103-2 is the slit 103.

[0072] The angle α between the center line of the first slit 103-1 and the thickness direction of the baffle 100 is the first angle. The first angle is not greater than 90 degrees. Preferably, the first angle is less than 90 degrees. For example, the first angle may be greater than or equal to 30 degrees and less than or equal to 60 degrees. The width of the first slit 103-1 and the width of the second slit 103-2 may be the same or substantially the same. The angle between the center line of the first slit 103-1 and the center line of the second slit 103-2 is the second angle. The second angle is not greater than 90 degrees minus the first angle.

[0073] The rotating device 200 rotates the baffle 100 from the first angle position to the second angle position by the first angle. When the baffle 100 is rotated to the second angle position, the width direction of the first slit 103-1 is consistent with or substantially consistent with the width direction of the radiation beam. The width dimension of the first slit 103-1 is greater than the width of the radiation beam incident at the position of the first slit 103-1. When the baffle 100 is rotated to the second angle position, the radiation beam can pass through the first slit 103-1.

[0074] The first slit 103-1 can be regarded as a slit whose center line is located at the second angular position. By setting the angle α to an angle less than 90 degrees, the minimum rotation angle required to rotate the baffle 100 from the first angular position to the second angular position can be reduced, thereby improving the response speed of the shutter from closing to opening.

[0075] On this basis, the predetermined angle position may further include a third angle position. The rotating device 200 may rotate the baffle 100 from the first angle position through the second angle position to the third angle position by the second angle. When the baffle 100 is rotated to the third angle position, the width direction of the second slit 103-2 is consistent or substantially consistent with the width direction of the radiation beam, and the width dimension of the second slit 103-2 is greater than the width of the radiation beam incident on the second slit 103-2. When the baffle 100 is rotated to the third angle position, the radiation beam can pass through the second slit 103-2.

[0076] The second slit 103-2 can be regarded as a slit obtained by rotating the first slit 103-1 by a second angle. Figure 2DAs shown, the angle between the center line of the second slit 103-2 and the thickness direction of the baffle 100 is 90 degrees, so the second slit can be regarded as a 90-degree slit. The angle between the center line of the first slit 103-1 and the thickness direction of the baffle 100 is α, and the angle between the center line of the first slit 103-1 and the center line of the second slit 103-2 (i.e., the second angle) is 90 degrees-α. The second slit 103-2 can be regarded as a slit obtained by rotating the first slit 103-1 by the second angle.

[0077] The combination of the first slit 103-1 and the second slit 103-2 covers all areas covered by the first slit 103-1 during the process of rotating the first slit 103-1 by the second angle. Therefore, when the baffle 100 is rotated to any angle position between the second angle position and the third angle position, the radiation beam can pass through the slit area covered by the combination of the first slit 103-1 and the second slit 103-2. That is, in the process of continuing to rotate the baffle 100 from the second angle position to the third angle position by the second angle, the shutter device is in the open state.

[0078] In some embodiments, the Figure 2A , Figure 2B The baffle 100 in the baffle 100 is cut so that the slit 103 in the baffle 100 after cutting includes a first slit 103-1 and a second slit 103-2. For example, the baffle 100 may include a first block 101 and a second block 102. The first block 101 and the second block 102 are both rectangular blocks. The gap between the first block 101 and the second block 102 forms the slit 103. The two opposite vertex angles of the two end faces of the first block 101 and the second block 102 that participate in forming the slit 103 can be cut along a predetermined inclination angle. The specific cutting method is not particularly limited in the present invention, as long as the slit 103 after cutting includes the first slit 103-1 and the second slit 103-2.

[0079] Figure 2E is shown with Figure 2D Schematic diagram of the corresponding shutter device in different states. Figure 2E In the embodiment, the angle (ie, the first angle) between the center line of the first slit 103-1 and the thickness direction of the baffle 100 is 45 degrees. The angle (ie, the second angle) between the center line of the first slit 103-1 and the center line of the second slit 103-2 is also 45 degrees.

[0080] Figure 2EThe left view in the figure is a schematic diagram of the state when the baffle 100 is rotated to the first angle position. When the baffle 100 is rotated to the first angle position, the radiation beam 11 emitted by the radiation source 10 is blocked by the baffle 100 and cannot be incident on the detection area from the slit 103 (i.e., the slit area composed of the first slit 103-1 and the second slit 103-2).

[0081] Figure 2E The middle view is a schematic diagram of the state when the baffle 100 is rotated 45 degrees from the first angular position to the second angular position. When the baffle 100 is rotated 45 degrees from the first angular position, the shutter device will switch from the closed state to the open state, and the radiation beam 11 emitted by the radiation source 10 can be incident on the detection area from the slit 103 (specifically the first slit 103-1).

[0082] Figure 2E The view on the right side of the middle is a schematic diagram of the state when the baffle 100 is further rotated 45 degrees from the second angle position to the third angle position. In the process of further rotating the baffle 100 from the second angle position by 45 degrees, the radiation beam 11 emitted by the radiation source 10 can pass through the slit area covered by the combination of the first slit 103-1 and the second slit 103-2. That is, in the process of further rotating the baffle 100 from the second angle position by 45 degrees, the shutter device is in the open state.

[0083] Figure 2F The figure is a schematic diagram showing the working principle of a shutter device according to an embodiment of the utility model.

[0084] and Figure 2E The difference is that an attenuation module 110 for attenuating the radiation beam may be provided in the slit 103 .

[0085] The attenuation module 110 may also be referred to as a radiation beam filter or filtering device. After the radiation beam 11 passes through the attenuation module 110, the radiation intensity of the radiation beam will decrease to a certain extent, and the amount of decrease depends on the material of the attenuation module 110 and the thickness of the attenuation module through which the radiation beam passes. The attenuation module 110 may be made of a material that can attenuate the intensity of the radiation beam. Typically, the attenuation module 110 may be copper or tin or an alloy or composite material thereof.

[0086] When the baffle 100 is rotated to different angular positions between the second angular position and the third angular position, the radiation beam 11 can be incident from the slit region to the detection region via the attenuation modules 100 with different thicknesses.

[0087] Figure 2F The left side view in the middle is a schematic diagram of the state when the baffle 100 is rotated to the first angle position. Figure 2F The middle view is a schematic diagram of the state when the baffle 100 is rotated 45 degrees from the first angular position to the second angular position. Figure 2F The middle right view is a schematic diagram of the state when the baffle 100 is further rotated 45 degrees from the second angle position to the third angle position.

[0088] See also Figure 2F When the baffle 100 is rotated to the second angle position, the thickness of the attenuation module 100 through which the radiation beam 11 passes is 2.8 mm, while when the baffle is rotated to the third angle position, the thickness of the attenuation module through which the radiation beam 11 passes is 2 mm. In addition, in the process of rotating the baffle from the second angle position to the third angle position, the thickness of the attenuation module through which the radiation beam 11 passes gradually decreases.

[0089] Under the action of the first slit, the second slit and the attenuation module, the shutter device of the utility model can not only improve the response speed of the shutter device from closing to opening, but also provide support for adjusting the intensity of the radiation beam incident to the detection area when the shutter is in the open state. For example, the angle to be rotated can be determined according to the required intensity of the radiation beam, and then the baffle is rotated to the second angle position and then the predetermined angle is continued to be rotated so that the radiation beam can pass through the slit area via the attenuation module of the predetermined thickness, so that the intensity of the radiation beam emitted from the slit area meets the requirements.

[0090] Under the condition that the intensity of the radiation beam generated by the radiation source remains unchanged, in order to ensure that the radiation scanning effect (image quality) at different scanning speeds and the radiation dose received by the to-be-inspected area (such as the trunk) and the avoidance area (such as the cab or the passenger compartment, which will receive a certain amount of scattered radiation from the radiation beam) in the inspected object are approximately the same, it is preferably necessary to adjust the intensity of the emitted radiation beam according to the scanning speed.

[0091] Exemplarily, the shutter device (specifically, the rotating device) can rotate to different angular positions according to external control commands in response to different moving speeds of the inspected object relative to the radiation source, so that the thickness of the attenuation module through which the radiation beam passes through the slit is different. Taking the first angle of 45 degrees mentioned above as an example, the thickness of the attenuation module is T, and the thickness of the attenuation module through which the radiation beam passes through the slit 103 is T'=T / sinθ (θ=0 degrees is the blocking position, and θ=45 degrees to 90 degrees is the allowed passing position). The smaller the moving speed and the smaller the rotation angle, the greater the thickness T' of the attenuation module passed through.

[0092] In summary, the slit 103 may include at least a first slit 103-1, which can be used to increase the response speed of the shutter device from closing to opening. Optionally, the slit 103 may also include a second slit 103-2, which can make the shutter device in an open state within a predetermined rotation angle range, and can provide support for setting an attenuation module in the slit 103 to adjust the intensity of the radiation beam.

[0093] In some embodiments, the shutter device 20 may further include an angle position sensor. The angle position sensor is used to detect the angle position of the baffle 100 and send the detected angle position to the control device, so that the control device sends a suitable control instruction to the rotating device 200 according to the current angle position of the baffle 100. The angle position sensor may be arranged in the rotating device 200. The angle position sensor may regard the detected angle position of the rotating device 200 as the angle position of the baffle 100. The rotating device 200 may receive the instruction sent by the control device and rotate a predetermined angle according to the instruction to rotate the baffle 100 to a desired angle position.

[0094] In some embodiments, a secondary collimator may be provided between the shutter device 20 and the object under inspection to further constrain the shape and / or size of the radiation beam; and / or a shielding device may be provided around the shutter device 20 to shield stray radiation generated when the baffle 100 blocks the radiation beam.

[0095] Figure 3A It is a schematic diagram showing a radiation beam emitting device in an open shutter state according to an embodiment of the utility model. Figure 3B It is a schematic diagram showing a radiation beam emitting device in a shutter closed state according to an embodiment of the utility model.

[0096] See also Figure 3A , Figure 3B Under the rotation of the rotating device, the position of the slit 103 can be changed by changing the position of the first stopper 101 and the second stopper 102, thereby allowing the radiation beam 11 to be emitted from the slit 103, or blocking the radiation beam 11 (i.e., not allowing the radiation beam 11 to be emitted from the slit 103).

[0097] Figure 3C It is a schematic structural diagram showing a shutter device according to an embodiment of the utility model.

[0098] See also Figure 3C, the shutter device may include but is not limited to a first block 101, a second block 102, a driving source 104, a linkage 105, a base 106 and a sensing component 107. The first block 101 and the second block 102 are arranged in the base 106, and may be connected to the driving source 104 through the linkage 105. The driving source 104 may control the rotation of the first block 101 and the second block 102 by driving the rotation of the linkage 105. The sensing component 107 may be used to determine whether the shutter structure is located at an accurate angular position. The sensing component 107 may also be referred to as an angular position sensor. Exemplarily, the sensing component 107 may be a proximity switch, and the shutter device must be rotated to a corresponding angular position to be opened or closed, and the proximity switch may be used to determine whether the shutter device is at an accurate angular position.

[0099] Figure 4A , Figure 4B Schematic diagrams showing the radiation beam emitting device in a shutter closed state at different viewing angles.

[0100] See also Figure 4A , Figure 4B , when the first stopper 101 and the second stopper 102 are rotated to Figure 4A , Figure 4B At the angle position shown (ie the first angle position mentioned above), the shutter is in a closed state, at which time the radiation beam 11 emitted by the radiation source 10 will be blocked by the first stopper 101 and the second stopper 102 and cannot pass through the slit 103 .

[0101] Figure 5A , Figure 5B Schematic diagrams showing the radiation beam emitting device in an open state at different viewing angles.

[0102] See also Figure 5A , Figure 5B , when the first stopper 101 and the second stopper 102 are rotated to Figure 5A , Figure 5B When the shutter is in the angular position shown (ie the second angular position mentioned above), the shutter will be switched to the open state, and the radiation beam 11 emitted by the radiation source 10 can pass through the slit 103 at this time.

[0103] The radiation beam emitting device of the utility model can be applied to any radiation beam generated by a radiation source to perform radiation imaging scanning on the inspected object (such as luggage, cargo, vehicles, etc.) to realize radiation inspection of the inspected object without unpacking the box, and is particularly suitable for non-stop rapid inspection scenarios of moving targets such as vehicles.

[0104] The utility model also provides a radiation inspection system.

[0105] Figure 6It is a schematic block diagram showing the basic structure of a radiation inspection system according to an embodiment of the present invention.

[0106] See also Figure 6 The radiation inspection system 600 may include a radiation beam emitting device 1, one or more detectors 12, and a control device 2. For the radiation beam emitting device 1, reference may be made to the above related description.

[0107] The detector 12 can be arranged at a predetermined position in the radiation inspection channel to receive imaging radiation beams transmitted or scattered from the inspected object in the inspection area. Different detectors 12 can be arranged at different positions to receive radiation beams transmitted or scattered from the inspected object at different angles.

[0108] The radiation inspection system 600 may also include a computer device for image processing and display analysis, and other auxiliary devices (such as a shielding device and a collimator).

[0109] Figure 7 A structural schematic diagram of a radiation inspection system according to another embodiment of the utility model is shown.

[0110] See also Figure 7 If the radiation inspection system is a top-illuminated inspection device, the radiation beam emitting device 1 can be arranged on the top of the device, the radiation beam 11 can be a fan-shaped thin beam projected downward from the top, and the detector 12 can be arranged on both sides and the bottom to scan and inspect the inspected object 14 passing below. The inspected object 14 can be but not limited to a cargo or passenger vehicle, and the part to be inspected (i.e., the inspected area) of the inspected object 14 can be but not limited to the cargo part, the cabin, the trunk and other areas. In addition, the radiation beam emitting device 1 can also be arranged on the side or bottom of the imaging device to form a side-illuminated or bottom-illuminated type as required.

[0111] Before the part to be inspected of the inspection object reaches the detection area, the radiation source in the radiation beam emitting device 1 can be started in advance to obtain a stable radiation beam. At this time, the shutter device is in a closed state (that is, the baffle 100 is in a first angle position), and the radiation beam emitted by the radiation source cannot enter the detection area. For example, the control device 2 can send a fourth instruction to the radiation beam emitting device 1 in response to the front end of the part to be inspected of the inspection object being a predetermined distance from the detection area. The radiation beam emitting device 1 can start the radiation source 10 in response to receiving the fourth instruction (at this time, the shutter is in a closed state, and the radiation beam is confined between the shutter and the radiation source). The size of the predetermined distance depends on the time required for the radiation source to emit a stable radiation beam from the start-up, and the moving speed of the inspection object relative to the radiation source 10. Specifically, the predetermined distance is positively correlated with the moving speed and is positively correlated with the time required for the radiation source to emit a stable radiation beam from the start-up.

[0112] The control device 2 may send a first instruction to the radiation beam emitting device 1 (such as the rotating device 200 in the radiation beam emitting device 1) in response to the portion to be inspected of the inspected object arriving at or about to arrive at the detection area. The radiation beam emitting device 1 (such as the rotating device 200) may rotate the baffle 100 from the first angle position to the second angle position in response to receiving the first instruction, so as to allow the radiation beam to be emitted from the slit to the detection area, and start radiation scanning of the portion to be inspected of the inspected object. For the first angle position and the second angle position, please refer to the relevant description above. Exemplarily, the first instruction may indicate the angle value that the rotating device 200 needs to rotate, and the rotating device 200 may rotate the angle value indicated by the first instruction to rotate the baffle 100 from the first angle position to the second angle position.

[0113] The control device 2 can also send a second instruction to the radiation beam emitting device 1 (such as the rotating device 200 in the radiation beam emitting device 1) in response to the end of the part to be inspected leaving (including when leaving or after leaving) or about to leave the detection area. In response to receiving the second instruction, the radiation beam emitting device 1 (such as the rotating device 200) rotates the baffle 100 from the second angle position to the first angle position to prohibit the radiation beam from passing through the slit, thereby stopping the radiation scanning of the inspected object. Exemplarily, the second instruction can indicate the angle value that the rotating device 200 needs to rotate, and the rotating device 200 can rotate the angle value indicated by the second instruction to rotate the baffle 100 from the second angle position to the first angle position.

[0114] The control device 2 may also send a third instruction to the radiation beam emitting device 1 (such as the rotating device 200 in the radiation beam emitting device 1) according to the moving speed of the inspected object. The radiation beam emitting device 1 (such as the rotating device 200) may rotate the baffle 100 by a second angle in response to receiving the third instruction so that the radiation beam is incident on the detection area via the attenuation module of a predetermined thickness in the slit. The predetermined thickness may be negatively correlated with the moving speed. That is, the smaller the moving speed of the inspected object relative to the radiation source, the greater the thickness of the attenuation module through which the radiation beam passes. Exemplarily, the control device 2 may determine the angle (i.e., the third angle) at which the baffle 100 needs to rotate according to the angular position of the baffle 100 and the moving speed of the inspected object, and send the angle to the radiation beam emitting device 1 to instruct the radiation beam emitting device 1 to rotate the baffle by a corresponding angle. That is, the third instruction may indicate the third angle at which the rotating device 200 needs to rotate. Thus, the emission intensity of the radiation beam can be adjusted quickly and in real time.

[0115] In summary, the utility model can realize that the radiation source can output the radiation beam quickly and stably through an ingenious shutter structure, thereby ensuring the quality of radiation imaging. At the same time, the emission intensity of the radiation beam can be quickly adjusted in real time through the filter material embedded in the shutter to adapt to different scanning speeds, thereby ensuring the scanning integrity and scanning quality in the application of fast scanning of moving targets.

[0116] The utility model belongs to the field of nuclear technology application, in particular, uses radiation beams generated by radiation sources (such as X-rays, gamma rays, neutrons, protons, etc., among which X-rays and gamma rays are the most widely used) to perform radiation imaging scans on luggage, goods, vehicles, etc., such as non-opening inspection of the contents of the inspected object, and is particularly suitable for fast scanning application scenarios where there are areas in the inspected object that are not allowed to be scanned (such as the cab, the crew cabin), such as non-stop fast inspection scenarios of moving targets such as vehicles. For example, see Fig. 8A As shown, when a mobile object to be inspected, such as a vehicle, reaches or is about to reach the radiation inspection position (i.e., the detection area), the shutter can be switched from a closed state to an open state, and the radiation beam emitted by the radiation source can be incident on the object to be inspected via the shutter and the collimator; see Figure 8B As shown, when a mobile inspected object such as a vehicle leaves or is about to leave the radiation inspection position (ie, the detection area), the shutter can be switched from an open state to a closed state to stop scanning.

[0117] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terms used herein are selected to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A shutter device for a radiation source, characterized in that: include: a baffle, the baffle being made of a material suitable for shielding a radiation beam, and having a slit therein; A rotating device is used to rotate the baffle to a predetermined angular position, wherein the predetermined angular position includes at least a first angular position and a second angular position; when the baffle is rotated to the first angular position, the radiation beam emitted by the radiation source cannot pass through the slit to enter the detection area; when the baffle is rotated to the second angular position, the radiation beam can pass through the slit to enter the detection area.

2. The shutter device according to claim 1, characterized in that: The baffle comprises a block, and the slit is arranged in the middle of the block; or The baffle includes two baffles, and the gap formed between the two baffles is the slit.

3. The shutter device according to claim 1, characterized in that: When the baffle is rotated to the first angular position, the size of the baffle in the radiation beam width direction is greater than the radiation beam width at the baffle position. When the baffle is rotated to the second angular position, the size of the slit in the radiation beam width direction is greater than the radiation beam width at the slit position.

4. The shutter device according to claim 1, characterized in that: The rotating device rotates the baffle from the first angle position to the second angle position by a first angle, wherein the first angle is not greater than 90 degrees. The slits include at least a first slit, and when the baffle is rotated to the second angular position, a width direction of the first slit is consistent or substantially consistent with a width direction of the radiation beam, The angle between the center line of the first slit and the thickness direction of the baffle is the first angle.

5. The shutter device according to claim 4, characterized in that: The predetermined angle position also includes a third angle position, and the rotating device rotates the baffle from the first angle position to the third angle position through the second angle position and continues to rotate the baffle by a second angle, wherein the second angle is not greater than 90 degrees minus the first angle. The slit further comprises a second slit, and when the baffle is rotated to the third angular position, the width direction of the second slit is consistent or substantially consistent with the width direction of the radiation beam, When the baffle is rotated to any angular position between the second angular position and the third angular position, the radiation beam can pass through the slit area covered by the combination of the first slit and the second slit.

6. The shutter device according to claim 5, characterized in that: The width of the first slit is the same as the width of the second slit, The angle between the center line of the first slit and the center line of the second slit is the second angle.

7. The shutter device according to claim 5, characterized in that: The slit is provided with an attenuation module for attenuating the radiation beam. When the baffle is rotated to different angular positions between the second angular position and the third angular position, the radiation beam can be incident from the slit region to the detection region via the attenuation modules having different thicknesses.

8. The shutter device according to claim 4, characterized in that: The first angle is greater than or equal to 30 degrees and less than or equal to 60 degrees.

9. The shutter device according to claim 1, characterized in that: Also includes: An angular position sensor, used for detecting the angular position of the baffle and sending the detected angular position to the control device; The rotating device receives the instruction sent by the control device, and rotates a predetermined angle according to the instruction to rotate the baffle to a desired angular position.

10. A radiation beam emitting device, characterized in that: include: a radiation source for emitting a radiation beam toward a detection area; and The shutter device according to any one of claims 1 to 9.

11. A radiation inspection system, characterized in that: include: The radiation beam emitting device according to claim 10; One or more detectors, arranged at predetermined positions in the radiation inspection channel, for receiving imaging radiation beams transmitted or scattered from the inspected object in the inspection area; The control device is used for sending a first instruction to the radiation beam emitting device in response to the part to be inspected of the inspected object reaching or about to reach the detection area, and the radiation beam emitting device rotates the baffle from the first angular position to the second angular position in response to the first instruction.

12. The radiation inspection system according to claim 11, characterized in that: The control device also sends a second instruction to the radiation beam emitting device in response to the end of the part to be inspected leaving or about to leave the detection area, and the radiation beam emitting device rotates the baffle from the second angular position to the first angular position in response to the second instruction.

13. The radiation inspection system according to claim 11, characterized in that: The control device also sends a third instruction to the radiation beam emitting device according to the moving speed of the inspected object, and the radiation beam emitting device continues to rotate the baffle by a third angle in response to the third instruction so that the radiation beam is incident on the detection area through an attenuation module of a predetermined thickness in the slit, wherein the predetermined thickness is negatively correlated with the moving speed.

14. The radiation inspection system according to claim 11, characterized in that: The control device also sends a fourth instruction to the radiation beam emitting device in response to the front end of the part to be inspected of the inspected object being a predetermined distance from the detection area, and the radiation beam emitting device starts the radiation source in response to the fourth instruction.

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