Rotary scanning type infrared imaging system and control method thereof

Abstract

The invention discloses a rotary scanning type infrared imaging system and a control method thereof, and belongs to the technical field of infrared imaging, and the system is composed of a U-shaped frame, a transverse rolling inner frame, a transverse rolling motor, a photoelectric slip ring, a pitching mirror, an infrared camera and the like. The control method comprises the following steps of: calibrating a black body to acquire a background signal, driving the transverse rolling motor to enable the transverse rolling inner frame to rotate and scan at a constant speed, adjusting the angle of the pitching mirror at a specific position, performing image motion compensation, changing the angle of the pitching mirror at different scanning positions, and controlling the imaging time of the infrared camera. If the second optical window enters or leaves the imaging view field, the pitching mirror is correspondingly adjusted, the optical axis penetrates through the corresponding window, the movement speed of the optical axis is controlled to be matched with the speed-height ratio to guarantee clear and continuous imaging, and efficient rotary scanning type infrared imaging is achieved. By controlling the system through the control method provided by the invention, the beneficial effects of high scanning efficiency and low requirement on the motor can be achieved.

Description

Technical Field

[0001] The present invention relates to the field of infrared imaging technology, and particularly to a rotary scanning infrared imaging system and a control method thereof. Background Art

[0002] Infrared imaging is a major remote sensing method in the aerospace field. It receives the infrared spectral radiation and reflected energy of ground object targets, has the advantages of passive detection and all-day and all-night detection, can obtain surface temperature information of large areas, and is widely used in many fields such as military, search and rescue, and agricultural and forestry environmental monitoring.

[0003] In the prior art, there are many scanning methods such as rotary scanning, reciprocating one-way scanning, and reciprocating two-way scanning. However, the imaging efficiency of rotary scanning is too low, which will lead to too long time to obtain a complete and clear image or the image quality is difficult to meet the requirements; the reciprocating one-way scanning and reciprocating two-way scanning methods have high requirements for the motor because the motor rotates in a reciprocating mode. Therefore, in the case of requiring fast response or large-area fast scanning imaging, this motor characteristic will become a technical bottleneck. Therefore, in the existing technology, there is a lack of a scanning system with high scanning efficiency and low requirements for the motor to meet the needs. Summary of the Invention

[0004] The present invention provides a rotary scanning infrared imaging system and a control method thereof to solve the defects of low scanning efficiency and high requirements for the motor in the prior art.

[0005] On the one hand, the present invention provides a rotary scanning infrared imaging system, including: a U-shaped frame with its concave surface facing downwards, and a black body fixedly connected to one end of the top wall of the concave surface; a roll inner frame disposed in the concave surface of the U-shaped frame, with roll shafts fixedly connected to both ends of the roll inner frame, and the roll shafts are rotatably connected to both sides of the U-shaped frame. The roll inner frame is respectively provided with a first optical window and a second optical window; a roll motor and an optical slip ring, wherein one of the roll shafts passes through the U-shaped frame and extends along the extension line of the roll shaft, and both the roll motor and the optical slip ring are fixedly connected to the roll shaft; a pitch mirror rotatably connected to the roll inner frame through a pitch shaft, located at the connection of the first optical window and the second optical window, and the pitch shaft is driven to rotate by a pitch motor; an infrared camera fixedly connected to the roll inner frame.

[0006] Optionally, the optical axis of the infrared camera is parallel to the axis of the roll shaft.

[0007] Optionally, the axis of the pitch shaft is perpendicular to the axis of the roll shaft.

[0008] Optionally, the wingspan direction of the pitch mirror is perpendicular to the axis of the roll axis. With the vertical angle of the pitch mirror being 0°, the rotation angle of the pitch mirror is not less than 90°.

[0009] On the other hand, the present invention also provides a control method for a rotary scanning infrared imaging system. The steps of the control method are as follows: S101. Perform blackbody calibration operation. By adjusting the positions of the roll inner frame and the pitch mirror, make the optical axis of the infrared camera point to the blackbody for imaging and synchronously measure the blackbody temperature to provide a benchmark for subsequent imaging calibration; S102. After completing the calibration, drive the roll inner frame to perform uniform continuous scanning, and start a comprehensive scan of the target area to obtain relevant data; S103. When a specific second optical window enters the imaging field of view, set the position of the pitch mirror and adjust the optical axis to pass through the second optical window and match the speed-height ratio to achieve image motion compensation as the roll inner frame rotates, so as to obtain a clear and continuous image in this field of view; S104. When the second optical window leaves the imaging field of view, switch the position of the pitch mirror so that the optical axis passes through the first optical window, and at the same time stop the infrared camera imaging to prepare for subsequent imaging through the first optical window; S105. When the first optical window enters the imaging field of view, adjust the position of the pitch mirror and control the movement of the optical axis with the rotation of the roll inner frame and compensate for image motion to obtain a clear and continuous image in this field of view; S106. When the first optical window leaves the imaging field of view, change the position of the pitch mirror so that the optical axis passes through the second optical window, and at the same time stop the infrared camera imaging to prepare for subsequent imaging through the second optical window; S107. Determine the imaging state of the infrared camera in specific steps, that is, stop imaging in some steps to avoid invalid data, and generate a pulse sequence according to the rotation angle command in some steps to achieve synchronous imaging to accurately obtain image data.

[0010] Optionally, the step S101 specifically includes: when performing the blackbody calibration, the roll inner frame rotates to the initial position, and the pitch mirror rotates to +45° (±5°), so that the optical axis of the infrared camera passes through the first optical window and points to the blackbody directly above for imaging for several seconds, and the blackbody synchronously completes the temperature measurement.

[0011] Optionally, the step S103 specifically includes: when the roll inner frame rotates so that the second optical window enters the lower 120° imaging field of view, the pitch mirror is at -45° (±5°), so that the optical axis of the infrared camera passes through the second optical window. As the roll inner frame continues to rotate, the pitch mirror controls the optical axis to move backward in the flight direction, and the moving speed needs to match the speed-height ratio to achieve continuous image motion compensation.

[0012] Optionally, the step S104 specifically includes: when the roll inner frame rotates so that the second optical window leaves the lower 120° imaging field of view, the pitch mirror rotates to +45° (±5°), so that the optical axis of the infrared camera passes through the first optical window.

[0013] Optionally, step S105 specifically includes: when the roll inner frame rotates so that the first optical window enters the lower 120° imaging field of view, the pitch mirror is at +45° (±5°), so that the optical axis of the infrared camera passes through the first optical window. As the roll inner frame continues to rotate, the pitch mirror controls the optical axis to move backward in the flight direction, and the moving speed needs to match the speed-height ratio to achieve continuous image motion compensation.

[0014] Optionally, step S106 specifically includes: when the roll inner frame rotates so that the first optical window leaves the lower 120° imaging field of view, the pitch mirror rotates to -45° (±5°), so that the optical axis of the infrared camera passes through the second optical window.

[0015] A rotary scanning type infrared imaging system and its control method provided by the present invention, at the system structure level, adopts a U-shaped frame, a roll inner frame, etc. to construct a reasonable layout. The roll motor and the pitch motor cooperate to disperse the motor pressure and overcome the limitation of the excessive requirement for motor torque in the traditional technology. In terms of the control method, first, accurate blackbody calibration is carried out. Subsequently, according to the scanning process, the pitch mirror angle is accurately adjusted at specific scanning positions and the image motion compensation is carried out by matching the speed-height ratio. At the same time, the imaging timing of the infrared camera is strictly controlled to ensure clear and coherent images, solving the problems of low imaging efficiency and high motor requirements in the prior art, and achieving the beneficial effects of improving the imaging efficiency and reducing the strict requirements on the motor. Description of the Drawings

[0016] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0017] Figure 1 is a side view of the rotary scanning type infrared imaging system of the present invention; Figure 2 is a schematic diagram of 120° field of view scanning of the single-sided mirror rotary scanning method in the prior art; Figure 3 is a schematic diagram of 120° field of view scanning of the double-sided mirror rotary scanning method in the prior art; Figure 4 is a schematic diagram of 120° field of view scanning of the whole machine rotary scanning method in the prior art; Figure 5 is a schematic diagram of 120° field of view scanning of the single-direction reciprocating scanning method in the prior art; Figure 6 is a schematic diagram of 120° field of view scanning of the double-direction reciprocating scanning method without pitch coordination in the prior art; Figure 7 It is a schematic diagram of 120° field of view scanning in the two-way reciprocating scanning mode under pitch coordination in the prior art; Figure 8 It is a schematic diagram of the cooperative pointing of the pitch mirror 9 during the roll continuous scanning process of the rotary scanning type infrared imaging system of the present invention; Figure 9 It is a timing diagram of the operation of the motor, camera and the change of the imaging area during the 360° rotation of the roll motor of the rotary scanning type infrared imaging system of the present invention, where T 扫描 is the time taken for the roll motor 3 to rotate 360°.

[0018] Reference numerals: 1. U-shaped frame; 2. Black body; 3. Roll motor; 4. Photoelectric slip ring; 5. Roll axis; 6. First optical window; 7. Second optical window; 8. Roll inner frame; 9. Pitch mirror; 10. Pitch motor; 11. Pitch axis; 12. Infrared camera. Detailed implementation manners

[0019] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without making creative efforts shall fall within the protection scope of the present invention.

[0020] As Figure 2 shown, in Figure 2 , the prior art adopts a single-sided mirror rotary scanning method to achieve 120° field of view scanning, with an imaging scanning angle of 60°, a scanning cycle rotation angle of 360°, and a scanning effective imaging efficiency of only 16.7%, resulting in a relatively low scanning efficiency. However, the motor is always in a one-way rotation mode, and the motor rotation speed can be very fast.

[0021] As Figure 3 shown, in Figure 3 , the prior art adopts a double-sided mirror rotary scanning method to achieve 120° field of view scanning, with an imaging scanning angle of 60°, a scanning cycle rotation angle of 180°, and a scanning effective imaging efficiency of only 33.3%, resulting in a relatively low scanning efficiency. However, the motor is always in a one-way rotation mode, and the motor rotation speed can be very fast.

[0022] As Figure 4 shown, in Figure 4In the prior art, a whole-machine rotation scanning method is adopted to achieve a 120° field of view scanning. Its imaging scanning angle is 120°, the scanning cycle rotation angle is 360°, and the scanning effective imaging efficiency is 33.3%. The scanning efficiency is relatively low, but the motor is always in a one-way rotation mode and the motor rotation speed can be very fast.

[0023] As Figure 5 shown, in Figure 5 the prior art, a one-way reciprocating scanning method is adopted to achieve a 120° field of view scanning. After the camera optical axis scans from the starting position to the left field of view edge position to the right field of view edge position, it needs to quickly return to the left field of view edge position for scanning, then quickly change direction and return to the left field of view edge position for scanning, and then repeat the above process. Its scanning effective imaging efficiency is generally controlled at 50%, and the maximum does not exceed 70%. The motor rotation is in a reciprocating mode, and the motor uniform scanning speed is relatively slow, otherwise it has extremely high requirements for the torque of the motor.

[0024] As Figure 6 shown, in Figure 6 the prior art, a two-way reciprocating scanning method without pitch cooperation is adopted to achieve a 120° field of view scanning. After the camera optical axis scans uniformly from the left field of view edge position to the right field of view edge position, it needs to quickly change direction and return to the right field of view edge position to start the back scan until it scans to the left field of view edge position, then quickly change direction and return to the left field of view edge position for scanning, and then repeat the above process. During this process, there is no pitch rotation mechanism for cooperation, and the corresponding ground scanning area is in a "zigzag" shape, resulting in missing gaps.

[0025] As Figure 7 shown, in Figure 7 the prior art, a two-way reciprocating scanning method with pitch cooperation is adopted to achieve a 120° field of view scanning. After the camera optical axis scans uniformly from the left field of view edge position to the right field of view edge position, it needs to quickly change direction and return to the right field of view edge position to start the back scan until it scans to the left field of view edge position, then quickly change direction and return to the left field of view edge position for scanning, and then repeat the above process. During this process, a pitch rotation mechanism is required for cooperation. During each uniform speed stage, the flying image shift is always compensated, and at the roll scanning commutation stage, it returns to the initial position of the flying image shift compensation to avoid the ground scanning area being in a "zigzag" shape. Its scanning effective imaging efficiency is generally not less than 80%, and the maximum does not exceed 90%. The motor rotation is in a reciprocating mode, and the motor uniform scanning speed is relatively slow, otherwise it has extremely high requirements for the torque of the motor.

[0026] Therefore, in summary, in the prior art, there are various scanning methods such as rotary scanning, reciprocating unidirectional scanning, and reciprocating bidirectional scanning. Among them, the imaging efficiency of rotary scanning is too low. Although the motor rotates at a high speed, the overall imaging efficiency is not high, which limits its application in scenarios with high requirements for imaging efficiency. For example, in aerial remote sensing tasks that require high resolution and large-area rapid imaging, the low imaging efficiency will result in too long a time to obtain a complete and clear image or the image quality being difficult to meet the requirements. In reciprocating unidirectional scanning and reciprocating bidirectional scanning, the motor rotates in a reciprocating mode, and the uniform scanning speed is slow, and the requirement for motor torque is high. This limits the improvement of the scanning speed. In flight operations, it is difficult to improve the flight operation speed ratio while ensuring the imaging quality (maintained by controlling the uniform scanning speed of the motor) to obtain higher task efficiency and more detailed ground object images. And in cases where rapid response or large-area rapid scanning imaging is required, this motor characteristic will become a technical bottleneck. For example, in the scenario of rapid imaging requirements for a rapidly moving target area in military reconnaissance, it is difficult to meet the requirements well.

[0027] To address this problem, the present invention provides a rotary scanning infrared imaging system. By using a U-shaped frame, a roll inner frame, etc., a reasonable layout is constructed. The roll motor and the pitch motor cooperate to disperse the motor pressure and overcome the limitation of the excessive requirement for motor torque in the traditional technology.

[0028] The present invention will be specifically described below with reference to the accompanying drawings.

[0029] Figure 1 FIG. is a side view of the rotary scanning infrared imaging system of the present invention. As shown in the figure, the system mainly includes a U-shaped frame 1, a roll inner frame 8, a roll motor 3, an optical slip ring 4, a pitch mirror 9, and an infrared camera 12. Among them, the infrared camera 12 is fixedly connected inside the roll inner frame 8. The concave surface of the U-shaped frame 1 faces downward, and a black body 2 is fixedly connected to one end of the top wall of the concave surface. The roll inner frame 8 is arranged inside the concave surface of the U-shaped frame 1. Both ends of the roll inner frame 8 are fixedly connected with roll shafts 5. The roll shafts 5 are rotatably connected to both sides of the U-shaped frame 1. The roll inner frame 8 is respectively provided with a first optical window 6 and a second optical window 7. One of the roll shafts 5 passes through the U-shaped frame 1 and extends along the extension line of the roll shaft 5. The roll motor 3 and the optical slip ring 4 are both fixedly connected to the roll shaft 5. The pitch mirror 9 is rotatably connected inside the roll inner frame 8 through a pitch shaft 11. It is located at the connection of the first optical window 6 and the second optical window 7. The pitch shaft 11 is driven to rotate by a pitch motor 10.

[0030] Based on the above, the rotary scanning infrared imaging system of the present invention uses a U-shaped frame 1, a roll inner frame 8, etc. to construct a reasonable layout. The roll motor 3 and the pitch motor 10 cooperate to disperse the motor pressure and overcome the limitation of the excessive requirement for motor torque in the traditional technology.

[0031] For further illustration of the system of the present invention, in a preferred embodiment of the present invention, the optical axis of the infrared camera 12 can be parallel to the axis of the roll axis 5. This is because when the roll inner frame 8 performs a roll motion, the direction of the optical axis of the camera is relatively stable, which is beneficial to maintaining continuous observation and imaging of the target during the roll process. For example, if the optical axis of the camera is not parallel to the roll axis, during the roll process, the angle of the light received by the camera will constantly change, which may cause problems such as image distortion or target loss. Therefore, the parallelism between the optical axis of the infrared camera 12 and the axis of the roll axis 5 helps to ensure that when the system performs a roll action, the infrared camera can stably receive the infrared radiation of the target in the designed direction, thereby improving the accuracy and stability of imaging.

[0032] For further illustration of the system of the present invention, in a preferred embodiment of the present invention, the axis of the pitch axis 11 can be perpendicular to the axis of the roll axis 5. This is because in terms of mechanical structure and motion control, this perpendicular relationship is very crucial. When the axis of the pitch axis 11 is perpendicular to the axis of the roll axis 5, it can make the pitch motion and the roll motion independent of each other and not interfere with each other. It can accurately control the attitude of the pitch mirror 9 and the position of the roll inner frame 8. For example, this perpendicular relationship ensures that the system can perform accurate and efficient two-dimensional motion control, improving the system's scanning and image shift compensation capabilities.

[0033] For further illustration of the system of the present invention, in a preferred embodiment of the present invention, the wingspan direction of the pitch mirror 9 can be perpendicular to the axis of the roll axis 5. Taking the vertical angle of the pitch mirror 9 as 0°, then, the rotation angle of the pitch mirror 9 can be not less than 90°. It should be noted here that the 90° of the rotation angle of the pitch mirror 9 is ±45° (±5°), that is to say, the pitch mirror 9 can rotate 45° respectively in the counterclockwise or clockwise order, and 5° is the tolerance. When the pitch mirror 9 rotates to +45°, the optical axis corresponds to the first optical window 6 and the conversion is completed. When the pitch mirror 9 rotates to -45°, the optical axis corresponds to the second optical window 7 and the conversion is completed.

[0034] Among them, the wingspan direction of the pitch mirror 9 is perpendicular to the axis of the roll axis 5, which further clarifies the installation attitude of the pitch mirror in the roll inner frame 8. Reducing optical loss and interference. In addition, the requirement that the rotation angle of the pitch mirror is not less than 90° enables single-circle scanning to achieve two ground scans. In practical applications, compared with the continuous rotation scanning in the prior art, the imaging efficiency is doubled, thereby improving the adaptability of the maximum speed-to-height ratio, so that the camera can still obtain the same clear and continuous images at a flight speed twice as high.

[0035] Based on the above, on the basis of the foregoing embodiments, the beneficial effects of this embodiment are as follows: In terms of structure, a reasonable layout such as a U-shaped frame and a roll inner frame is adopted, enabling the roll and pitch motors to cooperate to overcome the limitation of the excessively high motor torque requirement in the traditional technology; in terms of imaging effect, by making the optical axis of the infrared camera parallel to the axis of the roll axis, it is ensured that roll and pitch scanning do not cause image image rotation. Finally, through the measures in the system structure and control method, the beneficial effects of improving the imaging efficiency and reducing the stringent requirements for the motor are achieved.

[0036] And in order to further illustrate the system of the present invention, in a preferred embodiment of the present invention, the infrared camera 12 can select a cooled mid-wave infrared detector, with a focal plane array scale of 640×512 elements, where 640 is the flight direction, 512 is the wingspan direction, and the pixel size is 15μm. A mid-wave infrared optical lens with an F number of 3 and a focal length of 60mm is used. In addition, the infrared camera 12 has a 1D image motion compensation function, which can compensate for the image motion caused by scanning during the integration time.

[0037] The U-shaped frame 1 and the roll inner frame 8 are processed from aluminum alloy; the black body 2 is processed from copper, the front is roughened and painted with black paint, its emissivity is 0.98, and 4 temperature measuring resistors are installed on the back to achieve the precise temperature measurement function of the black body. After calibration, its measurement accuracy is better than 0.02°C; the roll motor 3 selects a low-speed torque motor including an angle sensor; the fiber optic rotary joint 4 selects an optoelectronic type to ensure the electrical connection with the outside when the roll inner frame 8 rotates continuously; the first optical window 6 and the second optical window 7 are made of germanium material, which can have a high optical transmittance in the mid-wave band.

[0038] The rotation speed of the motors (including the pitch motor 10 and the roll motor 3) is set to 312.5° / second, and the overlap rate is selected to be 10%. Then the rotation time for 120° is 0.384 seconds. At this time, 15 images are taken, and the frame period is 25.6 milliseconds. The maximum integration time is 8 milliseconds, the maximum image motion in the flight direction is 1.6 milliradians, and the maximum image motion in the scanning direction is 43.6 milliradians. Therefore, image motion compensation measures in the flight direction and the scanning direction are required. In addition, it takes 0.576 seconds for the roll to rotate 180° when scanning one row, and the maximum speed-height ratio adapted by the camera is 0.2 seconds -1 . Through the above implementation, it can meet the requirements for medium-wave infrared patrol coverage with a width of 1039 meters under the aircraft and a ground resolution of 7.5 cm at a speed of 60 m / s at an altitude of 300 meters for medium-sized aircraft, and achieve the search and detection of targets such as personnel, animals, vehicles, houses, and ships.

[0039] Based on this, the beneficial effects of this embodiment are as follows: In terms of imaging performance, a cooled mid-wave infrared detector with a specific area array scale and pixel size is combined with an image motion compensation function to achieve high-resolution, clear, and accurate imaging, which is conducive to target search and detection; in terms of material components, a germanium material optical window ensures high optical transmittance, and a blackbody for accurate temperature measurement provides a reliable temperature reference; in terms of mechanical and electrical performance, an optoelectronic slip ring ensures stable electrical connection during continuous rotation, and a suitable roll motor enables precise control and stable operation; in practical applications, by reasonably setting various parameters, it can meet the coverage mid-wave infrared patrol tasks of small and medium-sized aircraft at specific speeds and altitudes, achieving effective search and detection of various targets such as personnel and vehicles, and showing excellent performance in multiple dimensions such as imaging quality, system operation stability, and task adaptability.

[0040] Based on the same general inventive concept, the present invention also protects a control method, which is used to control the rotating scanning type infrared imaging system described in the foregoing embodiment. The control method provided by the embodiment of the present invention mainly includes the following steps: S101. Perform the calibration operation of the blackbody 2. By adjusting the positions of the roll inner frame 8 and the pitch mirror 9, make the optical axis of the infrared camera 12 point to the blackbody 2 for imaging and synchronously measure the temperature of the blackbody 2, providing a benchmark for subsequent imaging calibration.

[0041] S102. After completing the calibration, drive the roll inner frame 8 to perform uniform and continuous scanning, and start a full scan of the target area to obtain relevant data.

[0042] S103. When the specific second optical window 7 enters the imaging field of view, set the position of the pitch mirror 9 and adjust the optical axis to pass through the second optical window 7 and match the speed-altitude ratio to achieve image motion compensation as the roll inner frame 8 rotates, so as to obtain a clear and continuous image in this field of view.

[0043] S104. When the second optical window 7 leaves the imaging field of view, switch the position of the pitch mirror 9 to make the optical axis pass through the first optical window 6, and at the same time stop the imaging of the infrared camera 12 to prepare for the subsequent imaging of the first optical window 6; S105. When the first optical window 6 enters the imaging field of view, adjust the position of the pitch mirror 9 and control the movement of the optical axis and compensate for image motion as the roll inner frame 8 rotates, so as to obtain a clear and continuous image in this field of view.

[0044] S106. When the first optical window 6 leaves the imaging field of view, change the position of the pitch mirror 9 to make the optical axis pass through the second optical window 7, and at the same time stop the imaging of the infrared camera 12 to prepare for the subsequent imaging of the second optical window.

[0045] S107. Determine the imaging state of the infrared camera 12 in specific steps, that is, stop imaging in some steps to avoid invalid data, and generate a pulse sequence according to the rotation angle command to achieve synchronous imaging in some steps to accurately obtain image data.

[0046] Moreover, in steps S104 and S106, the infrared camera 12 stops imaging; in steps S103 and S105, the system generates an imaging pulse sequence according to the rotation angle command, such that the difference in the corresponding rotation angle commands of adjacent pulses is the single imaging field of view angle of the infrared camera, and the imaging pulses are sent to the infrared camera 12 to achieve synchronous imaging.

[0047] For the control method described in this embodiment, accurate blackbody calibration is first performed to establish an imaging standard. Subsequently, according to the scanning process, the elevation mirror angle is precisely adjusted at specific scanning positions and the image motion compensation is carried out by matching the speed-height ratio. At the same time, the imaging timing of the infrared camera is strictly controlled to ensure clear and continuous images, solving the problems of low imaging efficiency and high motor requirements in the prior art, and achieving the beneficial effects of improving the imaging efficiency and reducing the stringent requirements for the motor.

[0048] For further explanation of the above embodiment, in a preferred embodiment of the present invention, S101 may include: when the blackbody 2 is calibrated, the roll inner frame 8 rotates to the initial position, and the elevation mirror 9 rotates to +45° (±5°), so that the optical axis of the infrared camera 12 passes through the first optical window 6 and points to the blackbody 2 directly above for imaging for several seconds, and the blackbody synchronously completes temperature measurement.

[0049] Based on this, by rotating the roll inner frame to a specific initial position and the elevation mirror to +45° (±5°) when calibrating the blackbody 2, enabling the optical axis of the infrared camera 12 to pass through the first optical window 6 and point to the blackbody 2 directly above for imaging for several seconds and synchronously completing the temperature measurement of the blackbody 2, an accurate and stable starting point for the imaging standard can be established for the entire imaging system. This can effectively eliminate the uncertainty of the initial state of the system and ensure the accuracy and reliability of subsequent imaging data.

[0050] In a preferred embodiment of the present invention, S103 may include: when the roll inner frame 8 rotates such that the second optical window 7 enters the imaging field of view at 120° below, the elevation mirror 9 is at -45° (±5°), so that the optical axis of the infrared camera 12 passes through the second optical window 7. As the roll inner frame 8 continues to rotate, the elevation mirror 9 controls the optical axis to move backward in the flight direction, and the moving speed needs to match the speed-height ratio to achieve continuous image motion compensation.

[0051] Based on this, this method can timely and accurately activate the image motion compensation mechanism at the moment when the key imaging field of view enters, minimizing the image blurring problem caused by flight motion to the greatest extent, effectively improving the clarity and quality of the image in this specific field of view, and ensuring that high-quality image information can be obtained in this important imaging area, just like being able to precisely adjust the shooting angle and speed compensation in a high-speed moving vehicle to take clear photos of moving objects.

[0052] In a preferred embodiment of the present invention, S104 may include: when the roll inner frame 8 rotates such that the second optical window 7 moves out of the 120° imaging field of view below, the pitch mirror 9 rotates to +45° (±5°) such that the optical axis of the infrared camera 12 passes through the first optical window 6.

[0053] Based on this, this method can quickly and smoothly prepare for the switching of the imaging field of view of the next possible first optical window 6, reducing the transition time and imaging instability factors during the field of view switching process, and improving the coherence and efficiency of the overall imaging process of the system. Just like in a multi-task switching workflow, preparing for the next task in advance makes the entire work process more smooth and efficient.

[0054] In a preferred embodiment of the present invention, S105 specifically includes: when the roll inner frame 8 rotates such that the first optical window 6 enters the 120° imaging field of view below, the pitch mirror 9 is at +45° (±5°) such that the optical axis of the infrared camera 12 passes through the first optical window 6. As the roll inner frame 8 continues to rotate, the pitch mirror 9 controls the optical axis to move backward in the flight direction, and the moving speed needs to match the speed-height ratio to achieve continuous image motion compensation.

[0055] Based on this, this method optimizes the imaging field of view of the first optical window 6, ensures effectively overcoming the image motion problem during the up-field imaging process, improves the clarity and accuracy of the up-field imaging, and guarantees the integrity and clarity of the image information obtained in this field of view. Just like adjusting the device parameters specifically for the observation in a specific direction in a complex environment to obtain the best observation effect.

[0056] In a preferred embodiment of the present invention, S106 may include: when the roll inner frame 8 rotates such that the first optical window 6 moves out of the 120° imaging field of view below, the pitch mirror 9 rotates to -45° (±5°) such that the optical axis of the infrared camera 12 passes through the second optical window 7.

[0057] Based on this, this method makes a connection for the next round of cyclic scanning, enables the entire scanning imaging process to operate efficiently in a cycle, avoids the jamming and errors during the cyclic switching process, and guarantees the ability of the system to operate stably for a long time and continuously obtain high-quality images.

[0058] It should be understood that in various embodiments of the present invention, the magnitudes of the serial numbers of the above processes do not mean the order of execution. The order of execution of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present invention.

[0059] In addition, the terms "system" and "network" in this document are often used interchangeably herein. The term "and / or" in this document is merely a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally represents an "or" relationship between the associated objects before and after.

[0060] It should be understood that in the embodiments of the present invention, "B corresponding to A" means that B is associated with A, and B can be determined according to A. However, it should also be understood that determining B according to A does not mean determining B only according to A, and B can also be determined according to A and / or other information.

[0061] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed in this document can be implemented by electronic hardware, computer software, or a combination of the two. To clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described according to functions in the above description. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present invention.

[0062] Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working processes of the systems, devices, and units described above can refer to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0063] In several embodiments provided in this application, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division, and there can be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed coupling or direct coupling or communication connection to each other can be an indirect coupling or communication connection through some interfaces, devices, or units, and can also be in an electrical, mechanical, or other form of connection.

[0064] The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they can be located in one place, or can be distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiments of the present invention.

[0065] In addition, in each embodiment of the present invention, each functional unit may be integrated into one processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of a software functional unit.

[0066] Through the description of the above embodiments, those skilled in the art can clearly understand that the present invention can be implemented by hardware, or by firmware, or by a combination thereof. When implemented using software, the above functions can be stored in a computer-readable medium or transmitted as one or more instructions or codes on a computer-readable medium. The computer-readable medium includes computer storage media and communication media, where the communication media includes any medium that facilitates the transmission of a computer program from one place to another. The storage media can be any available medium that can be accessed by a computer. By way of example but not limitation: the computer-readable medium may include RAM, ROM, EEPROM, CD-ROM or other optical disc storage, magnetic disk storage media or other magnetic storage devices, or any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer. In addition, any connection may suitably be a computer-readable medium. For example, if the software is transmitted using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL) or wireless technologies such as infrared, radio and microwave from a website, server or other remote source, then the coaxial cable, fiber optic cable, twisted pair, DSL or wireless technologies such as infrared, wireless and microwave are included in the definition of the medium. As used in the present invention, disk and disc include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray disc, where disk generally magnetically replicates data, while disc optically replicates data using a laser. The above combinations should also be included within the protection scope of the computer-readable medium.

[0067] In summary, the above description is only a preferred embodiment of the technical solution of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A rotary scanning infrared imaging system, characterized in that, Comprising: A U-shaped frame (1), the concave surface of the U-shaped frame (1) facing downwards, and one end of the top wall of the concave surface is fixedly connected to a black body (2); A roll inner frame (8), the roll inner frame (8) is arranged within the concave surface of the U-shaped frame (1), both ends of the roll inner frame (8) are fixedly connected to a roll shaft (5), the roll shaft (5) is rotatably connected to both sides of the U-shaped frame (1), and a first optical window (6) and a second optical window (7) are respectively arranged on the roll inner frame (8); A roll motor (3) and a fiber optic rotary joint (4), one of the roll shafts (5) passes through the U-shaped frame (1) and extends along the extension line of the roll shaft (5), and both the roll motor (3) and the fiber optic rotary joint (4) are fixedly connected to the roll shaft (5); A pitch mirror (9), the pitch mirror (9) is rotatably connected within the roll inner frame (8) by means of a pitch shaft (11), it is located at the connection of the first optical window (6) and the second optical window (7), and the pitch shaft (11) is driven to rotate by means of a pitch motor (10); An infrared camera (12), the infrared camera (12) is fixedly connected within the roll inner frame (8).

2. The rotational scanning type infrared imaging system according to claim 1, wherein: The optical axis of the infrared camera (12) is parallel to the axis of the roll shaft (5).

3. The rotational scanning type infrared imaging system according to claim 1, wherein: The axis of the pitch shaft (11) is perpendicular to the axis of the roll shaft (5).

4. The rotational scanning type infrared imaging system according to claim 1, wherein: The wingspan direction of the pitch mirror (9) is perpendicular to the axis of the roll shaft (5). Taking the vertical angle of the pitch mirror (9) as 0°, the rotation angle of the pitch mirror (9) is not less than 90°.

5. A control method for a rotating-scanning infrared imaging system according to any one of claims 1 to 4, characterized in that, The steps of the control method are as follows: S101. Perform black body (2) calibration operation. By adjusting the positions of the roll inner frame (8) and the pitch mirror (9), make the optical axis of the infrared camera (12) point to the black body (2) for imaging and synchronously measure the temperature of the black body (2), providing a benchmark for subsequent imaging calibration; S102. After calibration is completed, drive the roll inner frame (8) to carry out uniform continuous scanning, and start a full scan of the target area to obtain relevant data; S103. When the specific second optical window (7) enters the imaging field of view, set the position of the pitch mirror (9) and adjust the optical axis to pass through the second optical window (7) and match the speed-height ratio to achieve image motion compensation as the roll inner frame (8) rotates, so as to obtain a clear and continuous image in this field of view; S104. When the second optical window (7) leaves the imaging field of view, switch the position of the pitch mirror (9) to make the optical axis pass through the first optical window (6), and at the same time stop the imaging of the infrared camera (12), preparing for subsequent imaging of the first optical window (6); S105. When the first optical window (6) enters the imaging field of view, adjust the position of the pitch mirror (9) and control the movement of the optical axis and compensate for image motion as the roll inner frame (8) rotates, so as to obtain a clear and continuous image in this field of view; S106. When the first optical window (6) leaves the imaging field of view, change the position of the pitch mirror (9) to make the optical axis pass through the second optical window (7), and at the same time stop the imaging of the infrared camera (12), preparing for subsequent imaging of the second optical window; S107. Define the imaging state of the infrared camera (12) in specific steps, that is, stop imaging in some steps to avoid invalid data, and generate a pulse sequence according to the rotation angle command in some steps to achieve synchronous imaging for accurately obtaining image data.

6. The control method according to claim 5, characterized in that, Step S101 specifically includes: when calibrating the blackbody (2), the roll inner frame (8) rotates to the initial position, and the pitch mirror (9) rotates to +45° (±5°), so that the optical axis of the infrared camera (12) passes through the first optical window (6) and points to the blackbody (2) directly above for imaging for several seconds, and the blackbody synchronously completes temperature measurement.

7. The control method according to claim 5, characterized in that Step S103 specifically includes: when the roll inner frame (8) rotates so that the second optical window (7) enters the 120° imaging field of view below, the pitch mirror (9) is at -45° (±5°), so that the optical axis of the infrared camera (12) passes through the second optical window (7). As the roll inner frame (8) continues to rotate, the pitch mirror (9) controls the optical axis to move backward in the flight direction, and the moving speed needs to match the speed-height ratio to achieve continuous image motion compensation.

8. The control method according to claim 5, wherein Step S104 specifically includes: when the roll inner frame (8) rotates so that the second optical window (7) leaves the 120° imaging field of view below, the pitch mirror (9) rotates to +45° (±5°), so that the optical axis of the infrared camera (12) passes through the first optical window (6).

9. The control method according to claim 5, wherein Step S105 specifically includes: when the roll inner frame (8) rotates so that the first optical window (6) enters the 120° imaging field of view below, the pitch mirror (9) is at +45° (±5°), so that the optical axis of the infrared camera (12) passes through the first optical window (6). As the roll inner frame (8) continues to rotate, the pitch mirror (9) controls the optical axis to move backward in the flight direction, and the moving speed needs to match the speed-height ratio to achieve continuous image motion compensation.

10. The control method according to claim 5, characterized in that Step S106 specifically includes: when the roll inner frame (8) rotates so that the first optical window (6) leaves the 120° imaging field of view below, the pitch mirror (9) rotates to -45° (±5°), so that the optical axis of the infrared camera (12) passes through the second optical window (7).

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