Control method and system for preventing thermal infrared imager from being burnt by sun

Abstract

The invention provides a control method and system for preventing a thermal infrared imager from being burnt by the sun, and the method comprises the following steps: obtaining a target infrared image in real time, and searching a to-be-confirmed target in the target infrared image; if the to-be-confirmed target exists in the target infrared image, obtaining a target coordinate and a target gray value of the to-be-confirmed target; if an absolute value of a difference value between the target gray value and a preset gray value is smaller than or equal to a first preset threshold value, calculating a target stepping angle of the aperture shutter according to the target coordinate; and controlling the blades of the aperture type shutter to rotate by the target stepping angle, so that the aperture type shutter shields the sun. According to the scheme, the infrared image of the target is acquired in real time and searched and analyzed, so that the target of the sun, which burns the thermal imager, can be found in time, and the real-time protection of the thermal infrared imager is realized.

Description

Technical Field

[0001] The present application relates to the technical field of infrared thermal imagers, and in particular to a control method and system for preventing infrared thermal imagers from being burned by the sun. Background Art

[0002] With the continuous development of infrared thermal imaging technology, infrared thermal imagers have been widely used in various fields, such as military, security, industrial detection, etc. However, in actual use, infrared thermal imagers face the risk of being burned by the sun. When the sun appears in the field of view of the infrared thermal imager, its strong infrared radiation may cause permanent damage to the detector of the thermal imager, affecting the performance and life of the thermal imager.

[0003] Traditional methods of preventing infrared thermal imagers from being sunburned are mainly through manual observation and adjustment, or the use of simple mechanical shielding devices. However, these methods have many shortcomings, such as low efficiency, low accuracy, and difficulty in real-time response of manual observation and adjustment; simple mechanical shielding devices often cannot accurately aim at the sun and cannot be dynamically adjusted according to changes in the sun's position.

[0004] In addition, although some existing infrared thermal imagers have certain automatic protection functions, they are usually based on fixed thresholds or rules for judgment, lacking flexibility and accuracy. For example, some thermal imagers only judge based on brightness values, which are easily interfered by other strong light sources, leading to misjudgment and misoperation. Summary of the invention

[0005] In view of the above-mentioned defects or deficiencies in the prior art, the present application aims to provide a control method and system for preventing an infrared thermal imager from being burned by the sun.

[0006] In a first aspect, the present application proposes a control method for preventing an infrared thermal imager from being burned by the sun, comprising the following steps:

[0007] Acquire a target infrared image in real time, and search for a target to be confirmed in the target infrared image;

[0008] If the target infrared image contains the target to be confirmed, then obtaining the target coordinates and target grayscale value of the target to be confirmed;

[0009] If the absolute value of the difference between the target grayscale value and the preset grayscale value is less than or equal to a first preset threshold, calculating the target step angle of the aperture shutter according to the target coordinates;

[0010] The blades of the aperture shutter are controlled to rotate at a target step angle so that the aperture shutter blocks the sun.

[0011] According to the technical solution provided in the embodiment of the present application, searching for the target to be confirmed in the infrared image at least includes the following steps:

[0012] Acquire a training sample set, wherein the training sample set includes at least a plurality of experimental infrared images, wherein the experimental infrared images include positive images with the sun and negative images without the sun, each of the experimental infrared images has a corresponding detection label, wherein the detection label includes a detected target and a non-detected target, and each of the positive images has a detection frame that frames the sun;

[0013] Taking all the experimental infrared images as input and the detection labels corresponding to all the experimental infrared images as output, training the initial model to obtain a detection model;

[0014] Inputting the target infrared image into the detection model to obtain the detection label corresponding to the target infrared image;

[0015] If the detection tag detects a target, it is determined that the target infrared image contains the target to be confirmed.

[0016] According to the technical solution provided in the embodiment of the present application, if the detection tag is a detected target, the detection model also outputs the detection frame;

[0017] The step of obtaining the target coordinates of the target to be confirmed comprises at least the following steps:

[0018] According to the detection frame, position information is obtained, where the position information at least includes the coordinates of the upper left corner of the detection frame, and the width and height of the detection frame;

[0019] The target coordinates of the target to be confirmed are obtained according to the position information.

[0020] According to the technical solution provided in the embodiment of the present application, the step of obtaining the target coordinates and the target grayscale value of the target to be confirmed includes obtaining the target grayscale value of the target to be confirmed, and the step of obtaining the target grayscale value of the target to be confirmed includes the following steps:

[0021] Obtaining grayscale values ​​of a plurality of detection points in the area within the detection frame;

[0022] The average value of all the grayscale values ​​is taken as the target grayscale value of the target to be confirmed.

[0023] According to the technical solution provided in the embodiment of the present application, the target step angle of the aperture shutter is calculated according to the target coordinates, specifically including the following steps:

[0024] Acquire imaging structure parameters of the infrared thermal imager and mechanical structure parameters of the aperture shutter, wherein the imaging structure parameters at least include the field of view angle and the image resolution of the target infrared image, the mechanical structure parameters at least include the angle range corresponding to one rotation of the blade, and the image resolution at least includes the number of pixels of image width and image height;

[0025] Obtaining the center of the field of view according to the number of pixels of the image width and the number of pixels of the image height and the field of view angle;

[0026] The target coordinates are converted into an angle deviation relative to the center of the field of view, and the target step angle is obtained according to the mechanical structure parameters and the angle deviation.

[0027] According to the technical solution provided in the embodiment of the present application, after converting the target coordinates into an angle deviation relative to the center of the field of view, before obtaining the target step angle according to the mechanical structure parameters and the angle deviation, the following steps are also included:

[0028] The direction type that needs to be adjusted is determined, where the direction type at least includes adjusting only the horizontal direction and adjusting both the horizontal direction and the vertical direction.

[0029] According to the technical solution provided in the embodiment of the present application, the angle deviation includes at least a horizontal angle deviation and a vertical angle deviation; the field of view angle includes at least a horizontal field of view angle and a vertical field of view angle;

[0030] The step of obtaining the target step angle according to the mechanical structure parameters and the angle deviation comprises at least the following steps:

[0031] When the direction type is to adjust only the horizontal direction, the target step angle is obtained according to the horizontal angle deviation and the horizontal field of view angle.

[0032] According to the technical solution provided in the embodiment of the present application, obtaining the target step angle according to the mechanical structure parameters and the angle deviation further includes the following steps:

[0033] When the direction type is to adjust the horizontal direction and the vertical direction at the same time, the horizontal step angle is obtained according to the horizontal angle deviation and the horizontal field angle; the vertical step angle is obtained according to the vertical angle deviation and the vertical field angle;

[0034] A weighted sum is performed on the vertical step angle and the horizontal step angle to obtain the target step angle.

[0035] According to the technical solution provided in the embodiment of the present application, after controlling the blades of the aperture shutter to rotate to a target step angle, the following steps are also included:

[0036] Searching for the target to be confirmed in the unblocked area, where the unblocked area is the area of ​​the infrared image of the target remaining after being blocked by the aperture shutter;

[0037] If the unblocked area does not contain the target to be confirmed, the aperture shutter is controlled to open after being blocked for a first preset time period.

[0038] In a second aspect, the present application proposes a control system for preventing an infrared thermal imager from being burned by the sun, which is used to implement the control method for preventing an infrared thermal imager from being burned by the sun as described above, comprising:

[0039] An acquisition module, wherein the acquisition module is configured to acquire a target infrared image in real time and search for a target to be confirmed in the target infrared image;

[0040] A calculation module, wherein the calculation module is configured to obtain the target coordinates and the target grayscale value of the target to be confirmed if the target infrared image contains the target to be confirmed;

[0041] The calculation module is further configured to calculate a target step angle of the aperture shutter according to the target coordinates if the absolute value of the difference between the target grayscale value and the preset grayscale value is less than or equal to a first preset threshold value;

[0042] A control module is configured to control the blades of the aperture shutter to rotate to a target step angle so that the aperture shutter blocks the sun.

[0043] In summary, the present application proposes a control method and system for preventing an infrared thermal imager from being burned by the sun. The control method for preventing an infrared thermal imager from being burned by the sun comprises the following steps: acquiring a target infrared image in real time, and searching for a target to be confirmed in the target infrared image; if there is a target to be confirmed in the target infrared image, acquiring the target coordinates and the target grayscale value of the target to be confirmed; if the absolute value of the difference between the target grayscale value and the preset grayscale value is less than or equal to a first preset threshold, calculating the target step angle of the aperture shutter according to the target coordinates; and controlling the blades of the aperture shutter to rotate at the target step angle so that the aperture shutter blocks the sun.

[0044] Compared with the prior art, the beneficial effect of the present application is that the present application can timely detect the sun, a target that can cause burns to the thermal imager, by acquiring the target infrared image in real time and performing search and analysis, thereby achieving real-time protection for the infrared thermal imager. When detecting whether the target is the sun, the target coordinates and grayscale value are combined for judgment, which improves the accuracy of detecting the sun target. Compared with the traditional judgment method based only on brightness value, it can effectively reduce misjudgment and misoperation, and avoid interference from other strong light sources. Moreover, the target step angle of the aperture shutter is calculated according to the target coordinates, thereby achieving dynamic shielding of the sun. No matter how the position of the sun in the field of view changes, it can ensure that the aperture shutter accurately moves to the corresponding position for shielding, thereby improving the adaptability and reliability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 A flowchart of the steps of a control method for preventing an infrared thermal imager from being burned by the sun provided in an embodiment of the present application;

[0046] Figure 2 The target to be confirmed provided in the embodiment of the present application is a grayscale distribution map of the sun;

[0047] Figure 3 The target to be confirmed provided in the embodiment of the present application is a grayscale distribution diagram of the moon (suspected to be the sun);

[0048] Figure 4 A schematic diagram of the structure of the aperture shutter provided in an embodiment of the present application.

[0049] The text annotations in the figure represent:

[0050] 1. Aperture shutter; 2. Blades. DETAILED DESCRIPTION

[0051] The present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant invention, rather than to limit the invention. It is also necessary to explain that, for ease of description, only the parts related to the invention are shown in the accompanying drawings.

[0052] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0053] Example 1

[0054] As mentioned in the background technology, in view of the problems in the prior art, this application proposes a control method for preventing infrared thermal imagers from being burned by the sun. Figure 1 As shown, the method comprises the following steps:

[0055] S1. Acquire a target infrared image in real time, and search for a target to be confirmed in the target infrared image;

[0056] Specifically, the target to be confirmed is searched according to shape or brightness, and the target to be confirmed may be the sun, or other luminous body except the sun, such as the moon.

[0057] S2. If the target infrared image contains the target to be confirmed, obtaining the target coordinates and target grayscale value of the target to be confirmed;

[0058] Specifically, when the target infrared image contains the target to be confirmed, it is necessary to further confirm the target to be confirmed to determine whether it is the sun. For example, if the target to be confirmed is the moon, there is no need to perform the following shielding operations because the moon will not cause burns to the infrared thermal imager.

[0059] S3, if the absolute value of the difference between the target grayscale value and the preset grayscale value is less than or equal to the first preset threshold, calculating the target step angle of the aperture shutter 1 according to the target coordinates;

[0060] Specifically, the preset grayscale value is the grayscale value of the sun, and the grayscale value of the sun can be simulated using professional optical simulation software. Specifically, the parameters of the sun and the characteristics of the thermal imager are input to simulate the imaging effect of the sun in the thermal imager under different conditions, thereby obtaining the preset grayscale value of the sun. This method can take into account more practical factors, such as atmospheric influences, the optical system of the thermal imager, etc., to improve the accuracy of the reference value. If the absolute value of the difference between the target grayscale value and the preset grayscale value is less than or equal to the first preset threshold, it means that the target to be confirmed is the sun.

[0061] Specifically, please refer to Figure 2 and Figure 3 As shown in Figure 2 As shown, the target to be confirmed is the sun. If the grayscale distribution diagram of the target to be confirmed is as follows Figure 3 As shown, the target to be confirmed is not the sun.

[0062] S4, controlling the blades 11 of the aperture shutter 1 to rotate to a target step angle, so that the aperture shutter 1 blocks the sun.

[0063] For details on the shape of the blade 11, please refer to Figure 4As shown, the blades 11 can be driven to rotate by a driving element built in it to drive it to open outward or contract inward. The control method uses advanced image processing technology and intelligent algorithms, and can automatically complete the detection and shielding of the sun without human intervention, thereby improving work efficiency and reducing labor costs. Wide application: It is suitable for various application scenarios, such as outdoor monitoring, industrial detection, security monitoring, etc., which provides a strong guarantee for the wide application of infrared thermal imagers. This embodiment identifies the target sun through deep learning + grayscale value discrimination method. Compared with the traditional methods of image segmentation and contour matching, it improves the detection efficiency and greatly improves the recognition accuracy. By driving the aperture shutter 1 to perform local shielding at the position of the sun, it can prevent the infrared thermal imager from being burned by the sun and ensure the acquisition of other target images in the scene.

[0064] In a preferred embodiment, searching for a target to be confirmed in the infrared image comprises at least the following steps:

[0065] Acquire a training sample set, wherein the training sample set includes at least a plurality of experimental infrared images, wherein the experimental infrared images include positive images with the sun and negative images without the sun, each of the experimental infrared images has a corresponding detection label, wherein the detection label includes a detected target and a non-detected target, and each of the positive images has a detection frame that frames the sun;

[0066] Specifically, a training sample set including positive images with the sun and negative images without the sun can greatly improve the accuracy of training.

[0067] Taking all the experimental infrared images as input and the detection labels corresponding to all the experimental infrared images as output, training the initial model to obtain a detection model;

[0068] Specifically, the YOLO model is selected as the initial model, which has the following advantages: the YOLO model regards target detection as a regression problem and directly predicts the detection box and category probability in a single network. This enables the YOLO model to achieve real-time frame rate when processing video streams, and can quickly obtain results when detecting unconfirmed targets in images, which is suitable for scenes with high real-time requirements. The YOLO model performs well in terms of accuracy, and can accurately detect unconfirmed targets in images and give their position and category information. Moreover, unlike some methods that can only detect a single object in an image, YOLO can detect multiple objects in an image, including the sun and other objects that may be similar to the sun. Understand the context of the object: When processing an image, YOLO considers the context information of the entire image, not just the local information. This gives YOLO an advantage in dealing with some complex situations that require understanding of contextual information, and can better detect the sun in the image. Easy to implement and train: The structure of YOLO is relatively simple and easy to implement. At the same time, because YOLO is an end-to-end system, its training process is also relatively simple.

[0069] Inputting the target infrared image into the detection model to obtain the detection label corresponding to the target infrared image;

[0070] If the detection tag detects a target, it is determined that the target infrared image contains the target to be confirmed.

[0071] In a preferred embodiment, if the detection tag is that a target is detected, the detection model also outputs the detection box;

[0072] The step of obtaining the target coordinates of the target to be confirmed comprises at least the following steps:

[0073] According to the detection frame, position information is obtained, where the position information at least includes the coordinates of the upper left corner of the detection frame, and the width and height of the detection frame;

[0074] The target coordinates of the target to be confirmed are obtained according to the position information.

[0075] In a preferred embodiment, the step of obtaining the target coordinates and the target grayscale value of the target to be confirmed includes obtaining the target grayscale value of the target to be confirmed, and the step of obtaining the target grayscale value of the target to be confirmed includes the following steps:

[0076] Obtaining grayscale values ​​of a plurality of detection points in the area within the detection frame;

[0077] The average value of all the grayscale values ​​is taken as the target grayscale value of the target to be confirmed.

[0078] In a preferred embodiment, the target stepping angle of the aperture shutter 1 is calculated according to the target coordinates, and specifically includes the following steps:

[0079] Acquire imaging structure parameters of the infrared thermal imager and mechanical structure parameters of the aperture shutter 1, wherein the imaging structure parameters at least include the field angle and the image resolution of the target infrared image, the mechanical structure parameters at least include the angle range corresponding to one rotation of the blade 11, and the image resolution at least includes the number of pixels of image width and image height;

[0080] Obtaining the center of the field of view according to the number of pixels of the image width and the number of pixels of the image height and the field of view angle;

[0081] The target coordinates are converted into an angle deviation relative to the center of the field of view, and the target step angle is obtained according to the mechanical structure parameters and the angle deviation.

[0082] In a preferred embodiment, after converting the target coordinates into an angular deviation relative to the center of the field of view and before obtaining the target step angle according to the mechanical structure parameters and the angular deviation, the following steps are also included:

[0083] The direction type that needs to be adjusted is determined, where the direction type at least includes adjusting only the horizontal direction and adjusting both the horizontal direction and the vertical direction.

[0084] In a preferred embodiment, the angle deviation includes at least a horizontal angle deviation and a vertical angle deviation; the field of view includes at least a horizontal field of view angle and a vertical field of view angle;

[0085] The step of obtaining the target step angle according to the mechanical structure parameters and the angle deviation comprises at least the following steps:

[0086] When the direction type is to adjust only the horizontal direction, the target step angle is obtained according to the horizontal angle deviation and the horizontal field of view angle.

[0087] In a preferred embodiment, obtaining the target step angle according to the mechanical structure parameters and the angle deviation further includes the following steps:

[0088] When the direction type is to adjust the horizontal direction and the vertical direction at the same time, the horizontal step angle is obtained according to the horizontal angle deviation and the horizontal field angle; the vertical step angle is obtained according to the vertical angle deviation and the vertical field angle;

[0089] A weighted sum is performed on the vertical step angle and the horizontal step angle to obtain the target step angle.

[0090] In a preferred embodiment, after controlling the blades 11 of the aperture shutter 1 to rotate by a target step angle, the following steps are further included:

[0091] Searching for the target to be confirmed in the unblocked area, where the unblocked area is the area of ​​the infrared image of the target remaining after being blocked by the aperture shutter 1;

[0092] If the unblocked area does not contain the target to be confirmed, the aperture shutter 1 is controlled to open after being blocked for a first preset time period.

[0093] Furthermore, before controlling the blades 11 of the aperture shutter 1 to rotate to a target step angle, the method further comprises the following steps:

[0094] Get the current time and real-time weather;

[0095] The step of controlling the blades 11 of the aperture shutter 1 to rotate to a target step angle specifically includes the following steps:

[0096] When the current time is other time periods than early morning or evening, and the real-time weather is other weather than cloudy or overcast, the blades 11 of the aperture shutter 1 are controlled to rotate to a target step angle.

[0097] Specifically, when the sun is close to the horizon, the radiation intensity of the sun is relatively weak, and the risk of burning the infrared thermal imager is low. In this case, even if the thermal imager detects that the sun is in the image, it can be left unshielded because its radiation energy is not enough to cause serious damage to the detector. When it is cloudy or blocked by clouds, the thick clouds will greatly reduce the radiation intensity of the sun, greatly reducing the solar radiation reaching the thermal imager. At this time, even if the sun is visible in the image, its impact on the thermal imager is small, so it can be considered not to block it.

[0098] Example 2

[0099] Based on Example 1, this embodiment proposes a control system for preventing an infrared thermal imager from being burned by the sun, which is used to implement the control method for preventing an infrared thermal imager from being burned by the sun as described in Example 1. Figure 2 As shown, including:

[0100] An acquisition module, wherein the acquisition module is configured to acquire a target infrared image in real time and search for a target to be confirmed in the target infrared image;

[0101] A calculation module, wherein the calculation module is configured to obtain the target coordinates and the target grayscale value of the target to be confirmed if the target infrared image contains the target to be confirmed;

[0102] The calculation module is further configured to calculate a target step angle of the aperture shutter 1 according to the target coordinates if the absolute value of the difference between the target grayscale value and the preset grayscale value is less than or equal to a first preset threshold value;

[0103] A control module is configured to control the blades 11 of the aperture shutter 1 to rotate to a target step angle so that the aperture shutter 1 blocks the sun.

[0104] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and its core ideas of this application. The above is only the preferred implementation method of this application. It should be pointed out that due to the limitations of textual expression and the objective existence of infinite specific structures, ordinary technicians in this technical field can make several improvements, modifications or changes without departing from the principles of the present invention, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the inventive concept and technical solution to other occasions without improvement, should be regarded as the scope of protection of this application.

Claims

1. A control method for preventing an infrared thermal imager from being burned by the sun, characterized in that: The following steps are involved: Acquire a target infrared image in real time, and search for a target to be confirmed in the target infrared image; If the target infrared image contains the target to be confirmed, then obtaining the target coordinates and target grayscale value of the target to be confirmed; If the absolute value of the difference between the target grayscale value and the preset grayscale value is less than or equal to a first preset threshold value, calculating the target step angle of the aperture shutter (1) according to the target coordinates; The blades (11) of the aperture shutter (1) are controlled to rotate at a target step angle so that the aperture shutter (1) blocks the sun.

2. The control method for preventing an infrared thermal imager from being burned by the sun according to claim 1, characterized in that: The step of searching for a target to be confirmed in the infrared image comprises at least the following steps: Acquire a training sample set, wherein the training sample set includes at least a plurality of experimental infrared images, wherein the experimental infrared images include positive images with the sun and negative images without the sun, each of the experimental infrared images has a corresponding detection label, wherein the detection label includes a detected target and a non-detected target, and each of the positive images has a detection frame that frames the sun; Taking all the experimental infrared images as input and the detection labels corresponding to all the experimental infrared images as output, training the initial model to obtain a detection model; Inputting the target infrared image into the detection model to obtain the detection label corresponding to the target infrared image; If the detection tag detects a target, it is determined that the target infrared image contains the target to be confirmed.

3. The control method for preventing an infrared thermal imager from being burned by the sun according to claim 2, characterized in that: If the detection tag is that a target is detected, the detection model also outputs the detection box; The step of obtaining the target coordinates of the target to be confirmed comprises at least the following steps: According to the detection frame, position information is obtained, where the position information at least includes the coordinates of the upper left corner of the detection frame, and the width and height of the detection frame; The target coordinates of the target to be confirmed are obtained according to the position information.

4. The control method for preventing an infrared thermal imager from being burned by the sun according to claim 2, characterized in that: The step of acquiring the target coordinates and the target grayscale value of the target to be confirmed includes acquiring the target grayscale value of the target to be confirmed, and the step of acquiring the target grayscale value of the target to be confirmed includes the following steps: Obtaining grayscale values ​​of a plurality of detection points in the area within the detection frame; The average value of all the grayscale values ​​is taken as the target grayscale value of the target to be confirmed.

5. The control method for preventing an infrared thermal imager from being burned by the sun according to claim 1, characterized in that: Calculating the target step angle of the aperture shutter (1) according to the target coordinates specifically comprises the following steps: Acquiring imaging structural parameters of the infrared thermal imager and mechanical structural parameters of the aperture shutter (1), wherein the imaging structural parameters at least include the field of view angle and the image resolution of the target infrared image, the mechanical structural parameters at least include the angle range corresponding to one rotation of the blade (11), and the image resolution at least includes the number of pixels of image width and the number of pixels of image height; Obtaining the center of the field of view according to the number of pixels of the image width and the number of pixels of the image height and the field of view angle; The target coordinates are converted into an angle deviation relative to the center of the field of view, and the target step angle is obtained according to the mechanical structure parameters and the angle deviation.

6. The control method for preventing an infrared thermal imager from being burned by the sun according to claim 5, characterized in that: After converting the target coordinates into an angular deviation relative to the center of the field of view and before obtaining the target step angle according to the mechanical structure parameters and the angular deviation, the following steps are also included: The direction type that needs to be adjusted is determined, where the direction type at least includes adjusting only the horizontal direction and adjusting both the horizontal direction and the vertical direction.

7. The control method for preventing an infrared thermal imager from being burned by the sun according to claim 6, characterized in that: The angle deviation at least includes a horizontal angle deviation and a vertical angle deviation; the field of view at least includes a horizontal field of view angle and a vertical field of view angle; The step of obtaining the target step angle according to the mechanical structure parameters and the angle deviation comprises at least the following steps: When the direction type is to adjust only the horizontal direction, the target step angle is obtained according to the horizontal angle deviation and the horizontal field of view angle.

8. The control method for preventing an infrared thermal imager from being burned by the sun according to claim 7, characterized in that: The step of obtaining the target step angle according to the mechanical structure parameters and the angle deviation further comprises the following steps: When the direction type is to adjust the horizontal direction and the vertical direction at the same time, the horizontal step angle is obtained according to the horizontal angle deviation and the horizontal field angle; the vertical step angle is obtained according to the vertical angle deviation and the vertical field angle; A weighted sum is performed on the vertical step angle and the horizontal step angle to obtain the target step angle.

9. The control method for preventing an infrared thermal imager from being burned by the sun according to claim 1, characterized in that: After controlling the blades (11) of the aperture shutter (1) to rotate to a target step angle, the method further comprises the following steps: Searching for the target to be confirmed in the unobstructed area, wherein the unobstructed area is the area of ​​the infrared image of the target remaining after being obstructed by the aperture shutter (1); If the unblocked area does not contain the target to be confirmed, the aperture shutter (1) is controlled to block for a first preset time period and then open.

10. A control system for preventing an infrared thermal imager from being burned by the sun, used to implement the control method for preventing an infrared thermal imager from being burned by the sun as claimed in any one of claims 1 to 9, characterized in that: include: An acquisition module, wherein the acquisition module is configured to acquire a target infrared image in real time and search for a target to be confirmed in the target infrared image; A calculation module, wherein the calculation module is configured to obtain the target coordinates and the target grayscale value of the target to be confirmed if the target infrared image contains the target to be confirmed; The calculation module is further configured to calculate a target step angle of the aperture shutter (1) according to the target coordinates if the absolute value of the difference between the target grayscale value and the preset grayscale value is less than or equal to a first preset threshold value; A control module is configured to control the blades (11) of the aperture shutter (1) to rotate to a target step angle so that the aperture shutter (1) blocks the sun.

Images