Laser beam matching control method suitable for low-illumination reconnaissance

Abstract

The invention relates to a laser beam matching control method suitable for low-illumination reconnaissance, and belongs to the technical field of airborne photoelectric reconnaissance monitoring. According to the method, the current view field is calculated through information such as the pixel size, the pixel number and the optical focal length of a current visible light television detector, and the longitudinal width of a current output image is obtained. Meanwhile, the beam divergence angle of the laser beam is calculated according to the mutual relation between the laser spot size specified by a user and the visible light image, so that the focal length of the current laser illuminator is deduced, and the brightness and definition of the visible light image in a key reconnaissance area are improved under the low-illumination condition; therefore, the man-machine effect in the low-illumination reconnaissance evidence obtaining process is improved

Description

Technical Field

[0001] The invention belongs to the technical field of airborne photoelectric reconnaissance and surveillance, and in particular relates to a laser beam matching control method suitable for low-illumination reconnaissance. Background Art

[0002] When conducting reconnaissance and evidence collection of key targets in a low-light environment, the images obtained by traditional visible light televisions are basically completely dark and have obvious noise points because the illumination is lower than the minimum acceptable value of the visible light detector. Although infrared thermal imagers can work all day to scout targets, infrared images can usually only provide the outline of the target, lack sufficient detailed information, and cannot meet the needs of high-precision evidence collection. In the prior art, the fields of view of the two sensors, visible light television and laser illuminator, are usually operated independently. When the visible light television changes the field of view, the beam divergence angle of the laser illuminator remains unchanged; when the laser illuminator changes the beam divergence angle, the field of view of the visible light television remains unchanged. When the laser illumination spot is larger than the longitudinal field of view of the visible light television, some laser illumination loss will occur; and when the laser illumination spot is smaller than the longitudinal field of view of the visible light television, the laser spot illumination will be too concentrated and the illumination area will be too small. Therefore, how to adjust the spot size of the laser illuminator in real time when the field of view of the visible light television changes so that it matches the optimal position has become a key issue in improving the image quality of night reconnaissance and evidence collection. Based on this, it is particularly important to design a laser beam matching control method suitable for low-illumination reconnaissance.

[0003] The present invention proposes an improved device and method, which ensures that the laser illumination spot always covers a constant field of view of the television by intelligently and synchronously adjusting the field of view and beam divergence angle of a visible light television and a laser illuminator, thereby reducing the energy loss of the illuminator and improving the image quality in the process of reconnaissance and evidence collection at night or in low illumination environments. Summary of the invention

[0004] 1. Technical issues to be resolved

[0005] The technical problem to be solved by the present invention is how to provide a laser beam matching control method suitable for low-illuminance reconnaissance, so as to solve the problem of adjusting the spot size of the laser illuminator in real time to match it to the optimal position when the visible light television field of view changes.

[0006] (II) Technical solution

[0007] In order to solve the above technical problems, the present invention proposes a laser beam matching control method suitable for low-illumination reconnaissance, which comprises the following steps:

[0008] Step 1: When the visible light television adjusts the focal length or field of view, its status data is sent to the control unit in real time;

[0009] Step 2: The user sets the size of the laser spot that occupies the visible light image, and the control unit analyzes the state data, calculates the laser beam divergence angle, and obtains the target focal length value required by the corresponding laser illuminator according to the laser beam divergence angle;

[0010] Step 3: The control unit sends an adjustment instruction to the laser illuminator, where the adjustment instruction includes a target focal length value;

[0011] Step 4: The laser illuminator adjusts its focal length according to the received adjustment instruction;

[0012] Step 5: The laser illuminator feeds back the spot data to the control unit, and verifies whether the laser spot adjustment meets expectations based on the feedback data. If it meets expectations, execute step 6. If deviation is found, generate and send a corrected adjustment instruction, and execute step 3.

[0013] Step 6: The control unit verifies and optimizes the visual matching;

[0014] Step 7: Through a friendly human-computer interaction interface, the status, adjustment process and results of the visible light television and laser illuminator are displayed to the user in real time.

[0015] (III) Beneficial effects

[0016] The present invention proposes a laser beam matching control method suitable for low-illumination reconnaissance, and the beneficial effects of the present invention are as follows:

[0017] (I) The present invention realizes precise matching of laser beams between visible light television and laser illuminator in different fields of view through an intelligent synchronous adjustment mechanism. The spot of the laser illuminator can always cover the center of the field of view of the visible light television or the user-specified area, avoiding the situation in which the laser spot cannot completely cover the field of view in the traditional method, ensuring that high-quality images can be captured even in low-light environments.

[0018] (ii) The present invention significantly improves the image quality in the reconnaissance and evidence collection process in low-light environments by adjusting the focal length and size of the laser illuminator in real time. Combined with advanced image processing algorithms such as denoising, contrast enhancement and detail enhancement, the system can provide clear and detailed images, which is of great significance for reconnaissance and evidence collection.

[0019] (III) The present invention intelligently adjusts the beam divergence range of the laser illuminator to ensure that the laser spot size matches the TV field of view, thereby reducing the waste of lighting energy. When adjusting the focal length of a traditional illuminator, the laser spot may be too large or too small, resulting in low energy utilization. The present invention effectively avoids this problem and improves the energy efficiency of the system.

[0020] (IV) The present invention has a high degree of automatic adjustment capability. The control unit monitors the status data of the visible light television and the laser illuminator in real time and makes dynamic adjustments. The status data feedback mechanism of the laser illuminator ensures that the system operates under closed-loop control, making the laser spot adjustment more accurate and reliable, and reducing human intervention and adjustment errors.

[0021] (V) The present invention includes a friendly human-computer interaction interface, through which users can monitor and operate the system in real time. The interface displays the working status, adjustment process and results of the visible light television and laser illuminator, and users can perform necessary manual intervention and adjustment, thereby improving the ease of use and operating efficiency of the system.

[0022] (VI) The laser beam matching control method of the present invention is applicable to low-illumination reconnaissance and has strong versatility and engineering application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a flow chart of the method of the present invention;

[0024] Figure 2 This is a schematic diagram of the matching of the TV field of view and the illuminator field of view. DETAILED DESCRIPTION

[0025] In order to make the purpose, content and advantages of the present invention more clear, the specific implementation methods of the present invention are further described in detail below in conjunction with the drawings and examples.

[0026] The present invention belongs to the technical field of airborne optoelectronic reconnaissance and surveillance, and specifically relates to a method for matching and controlling visible light television and laser illumination beams. The current field of view is calculated by using information such as the current visible light television detector pixel size, the number of detector pixels, and the optical focal length to obtain the longitudinal width of the current output image. At the same time, according to the relationship between the laser spot size and the visible light image specified by the user, the beam divergence angle of the laser beam is calculated, thereby inferring the current focal length of the laser illuminator, thereby achieving an improvement in the brightness and clarity of the visible light image in the key reconnaissance area under low illumination conditions, thereby improving the human-machine efficiency in the low illumination reconnaissance and evidence collection process.

[0027] The problem to be solved by the present invention is that when using visible light television for reconnaissance and evidence collection in a low-light environment, a laser illuminator is required to cooperate. In manual mode, the field of view of the laser illuminator cannot match the field of view of the visible light television in real time, which will cause energy waste, which is also a disadvantageous factor in the process of reconnaissance and evidence collection.

[0028] In order to solve the above technical problems, the present invention provides a laser beam matching control method suitable for low-light reconnaissance. The method integrates the laser illuminator and the visible light television on one device, forms a unified formula through rigorous theoretical derivation, and realizes calculation and communication on the central control unit. The method can automatically control the focal length of the laser illuminator while adjusting the focal length of the visible light television, thereby realizing more intelligent and convenient reconnaissance and evidence collection operations.

[0029] The flow chart of the method of the present invention is as follows Figure 1 As shown, it mainly includes the following steps:

[0030] Step 1: When the visible light television adjusts the focus or field of view, its status data is sent to the control unit in real time:

[0031] When the focal length or field of view of the visible light TV changes, the TV's control unit will monitor its current status data in real time, including but not limited to the detector pixel size p, the total number of detector lateral pixels N, the optical focal length value f, etc., and transmit these status data to the central control unit in real time through the visible light TV's built-in communication module.

[0032] Step 2: The user sets the size of the laser spot that occupies the visible light image, and the control unit analyzes the status data, calculates the laser beam divergence angle, and obtains the target focal length value required by the corresponding laser illuminator according to the laser beam divergence angle:

[0033] After receiving the status data, the control unit parses and processes the status data. According to the changes in the focal length and field of view of the visible light TV, as well as the size of the visible light image occupied by the illumination spot set by the user, the control unit uses a preset algorithm to calculate the beam divergence angle of the laser beam, and then derives the required illumination target focal length value to ensure that the laser spot can cover the field of view of the visible light TV. This calculation process takes into account the field of view change characteristics of the visible light TV and the optimal matching relationship between the laser spot coverage range, ensuring that under the user's settings, the laser spot can perfectly cover the constant field of view of the visible light TV. The ratio α of the lateral length of the laser spot to the lateral length of the visible light image is used as the proportion of the laser spot occupied by the visible light image set by the user, that is, The current field of view is calculated by using the current visible light TV detector pixel size, the total number of detector horizontal pixels, the optical focal length and other information to obtain the current visible light TV horizontal field of view FOV. Where d = p·N, d is the length of the detector. According to the ratio of the lateral length of the laser spot to the lateral length of the visible light image, α, the length d occupied by the lateral diameter of the laser spot is calculated. c =D c ·p, where D c =α·N is the number of pixels occupied by the lateral diameter of the laser spot. Then the laser beam divergence angle is Then, the target focal length value required for the corresponding laser illuminator is obtained according to the laser beam divergence angle. Since there is a one-to-one correspondence between the laser beam divergence angle and the focal length for a specific laser illuminator, the required target focal length value can be directly obtained without additional calculation.

[0034] Step 3: The control unit sends an adjustment instruction to the laser illuminator, where the adjustment instruction includes a target focal length value;

[0035] After completing the calculation of the target focal length value of the required laser illuminator, the control unit generates the corresponding adjustment instruction and sends it to the illuminator via wired or wireless communication. The adjustment instruction includes parameters such as the target focal length value to ensure that the laser illuminator can respond quickly and accurately.

[0036] Step 4: The laser illuminator adjusts its focal length according to the received adjustment instruction:

[0037] After the laser illuminator receives the adjustment command, the internal focusing mechanism starts working immediately, and by adjusting its optical elements, the focal length and size of the laser spot can be precisely adjusted. The adjustment process of the laser illuminator has high precision and high response speed, ensuring that the laser spot can quickly cover the center of the field of view of the visible light TV or the user-specified area.

[0038] Step 5: The laser illuminator feeds back the spot data to the control unit, and verifies whether the laser spot adjustment meets expectations based on the feedback data. If it meets expectations, execute step 6. If deviation is found, generate and send a corrected adjustment instruction, and execute step 3.

[0039] In order to ensure the closed-loop control of the system, the laser illuminator will feedback its current spot data (such as laser spot focal length, size, etc.) to the control unit after completing the focal length adjustment of the laser beam. The control unit verifies whether the laser spot adjustment meets expectations by parsing these feedback data. If a deviation is found, the control unit will further send a corrected adjustment instruction and execute step three to ensure that the final laser spot coverage effect is optimal. For example, after zooming, the control unit obtains the focal length value of the current laser illuminator. If there is a deviation from the calculated focal length value, the deviation data is sent as a corrected adjustment instruction.

[0040] Step 6: The control unit verifies and optimizes the visual matching;

[0041] After the laser illuminator completes the adjustment of the laser beam divergence angle and feeds back its spot data to the control unit, the control unit can also perform visual matching verification through the image captured in real time by the visible light TV. The control unit analyzes the image captured by the visible light TV to confirm whether the laser spot accurately covers the center of the field of view or the user-specified area (that is, the user sets the size of the laser spot to occupy the visible light image). If a deviation in the laser spot coverage is found, the control unit will perform real-time optimization and adjustment to further accurately match the laser spot with the visible light TV field of view.

[0042] Step 7: Through a friendly human-computer interaction interface, the status, adjustment process and results of the visible light television and laser illuminator are displayed to the user in real time, thereby achieving good human-computer interaction;

[0043] After the above steps are completed, the system displays the status, adjustment process and results of the visible light TV and laser illuminator to the user in real time through a friendly human-computer interaction interface. The user can understand the current working status of the system through the interface and make necessary manual intervention and adjustments. The system is designed with a simple operation interface and intuitive feedback information to ensure that users can easily and effectively operate and monitor the entire system to achieve the best user experience.

[0044] Embodiment 1:

[0045] The preferred embodiment of the present invention is a method for controlling the matching of laser beams in a visible light television reconnaissance and evidence collection device installed in a low-light environment. The device is composed of a visible light television, a central control unit, and a laser illuminator. The central control unit has a communication module, an I / O, a PWM module, a microprocessor, and a laser beam control software package. The visible light television is responsible for sending data to the central control unit, and the central control unit is responsible for calculating the required laser beam divergence angle and transmitting relevant control instructions to the laser illuminator, thereby controlling the size of the laser spot.

[0046] Step 1: After the visible light TV is powered on, the device is initialized, and the detector pixel size is set to 19.6 μm, the total number of detector lateral pixels is set to 1920, and the optical focal length is set to 6.5 mm;

[0047] Step 2. The user sets the ratio of the lateral length of the laser spot to the lateral length of the visible light image to be 0.5625. After receiving the visible light TV status data and the user-set data, the control unit parses and calculates these data. The horizontal field angle of the current visible light TV is calculated to be, after converting radians into degrees, the horizontal field angle of the visible light TV is 142.6 degrees. According to the ratio of the lateral length of the laser spot to the lateral length of the visible light image, calculate the number of pixels occupied by the lateral diameter of the laser spot. Then the laser beam divergence angle is, after converting radians into degrees, the laser beam divergence angle is 117.4 degrees, and then according to the crown of the laser beam divergence angle and the focal length, the corresponding laser illuminator required focal length value is deduced to be 7.3mm.

[0048] Step 3: After completing the calculation of the required focal length of the laser illuminator, the control unit sends an adjustment instruction (0X10) to the laser illuminator.

[0049] Step 4: If the laser lighting receives 0X10, the internal focusing mechanism starts working immediately and adjusts the focal length to the corresponding value by adjusting its optical elements.

[0050] Step 5: After completing the 0X10 command, the laser illuminator feeds back the current focal length of the spot to the control unit. The control unit verifies whether the focal length adjustment meets the preset conditions. If there is a deviation, it sends a correction command.

[0051] Step 6: The visible light TV captures the image, and the central processor identifies whether the light spot accurately covers the center of the field of view or the user-specified area. If there is a deviation, the control unit optimizes and adjusts in real time.

[0052] Step 7: The control unit displays the device status, adjustment process and results to the user in real time.

[0053] Beneficial effects of the present invention:

[0054] (I) The present invention realizes precise matching of laser beams between visible light television and laser illuminator in different fields of view through an intelligent synchronous adjustment mechanism. The spot of the laser illuminator can always cover the center of the field of view of the visible light television or the user-specified area, avoiding the situation in which the laser spot cannot completely cover the field of view in the traditional method, ensuring that high-quality images can be captured even in low-light environments.

[0055] (ii) The present invention significantly improves the image quality in the reconnaissance and evidence collection process in low-light environments by adjusting the focal length and size of the laser illuminator in real time. Combined with advanced image processing algorithms such as denoising, contrast enhancement and detail enhancement, the system can provide clear and detailed images, which is of great significance for reconnaissance and evidence collection.

[0056] (III) The present invention intelligently adjusts the beam divergence range of the laser illuminator to ensure that the laser spot size matches the TV field of view, thereby reducing the waste of lighting energy. When adjusting the focal length of a traditional illuminator, the laser spot may be too large or too small, resulting in low energy utilization. The present invention effectively avoids this problem and improves the energy efficiency of the system.

[0057] (IV) The present invention has a high degree of automatic adjustment capability. The control unit monitors the status data of the visible light television and the laser illuminator in real time and makes dynamic adjustments. The status data feedback mechanism of the laser illuminator ensures that the system operates under closed-loop control, making the laser spot adjustment more accurate and reliable, and reducing human intervention and adjustment errors.

[0058] (V) The present invention includes a friendly human-computer interaction interface, through which users can monitor and operate the system in real time. The interface displays the working status, adjustment process and results of the visible light television and laser illuminator, and users can perform necessary manual intervention and adjustment, thereby improving the ease of use and operating efficiency of the system.

[0059] (VI) The laser beam matching control method of the present invention is applicable to low-illumination reconnaissance and has strong versatility and engineering application value.

[0060] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A laser beam matching control method suitable for low-light reconnaissance, characterized in that: The method comprises the following steps: Step 1: When the visible light television adjusts the focal length or field of view, its status data is sent to the control unit in real time; Step 2: The user sets the size of the laser spot that occupies the visible light image, and the control unit analyzes the state data, calculates the laser beam divergence angle, and obtains the target focal length value required by the corresponding laser illuminator according to the laser beam divergence angle; Step 3: The control unit sends an adjustment instruction to the laser illuminator, where the adjustment instruction includes a target focal length value; Step 4: The laser illuminator adjusts its focal length according to the received adjustment instruction; Step 5: The laser illuminator feeds back the spot data to the control unit, and verifies whether the laser spot adjustment meets expectations based on the feedback data. If it meets expectations, execute step 6. If deviation is found, generate and send a corrected adjustment instruction, and execute step 3. Step 6: The control unit verifies and optimizes the visual matching; Step 7: Through a friendly human-computer interaction interface, the status, adjustment process and results of the visible light television and laser illuminator are displayed to the user in real time.

2. The laser beam matching control method for low-illumination reconnaissance as claimed in claim 1, characterized in that: The step one specifically includes: when the focal length or field of view of the visible light TV changes, the TV control unit will monitor its current status data in real time, including: detector pixel size p, total number of detector lateral pixels N, optical focal length value f, and transmit these status data to the central control unit in real time through the communication module built into the visible light TV.

3. The laser beam matching control method for low-illumination reconnaissance as claimed in claim 2, characterized in that: The step 2 specifically includes: after receiving the status data, the control unit parses and processes the status data, and according to the changes in the focal length and field of view of the visible light TV, and the size of the visible light image occupied by the illumination spot set by the user, the control unit uses a preset algorithm to calculate the beam divergence angle of the laser beam, and then derives the required illumination target focal length value, ensuring that the laser spot can cover the field of view of the visible light TV.

4. The laser beam matching control method for low-light reconnaissance as claimed in claim 3, characterized in that: The preset algorithm includes: taking the ratio of the lateral length of the laser spot to the lateral length of the visible light image as the user-set ratio of the laser spot to the visible light image, that is, Among them, L Source is the lateral length of the laser spot, L TV is the horizontal length of the visible light image; The current field of view is calculated by the current visible light TV detector pixel size, the total number of detector horizontal pixels, and the optical focal length information to obtain the current visible light TV horizontal field of view FOV: Wherein, d = p·N, d is the length of the detector; p is the pixel size of the visible light television detector, N is the total number of lateral pixels of the detector, and f is the optical focal length information; According to the ratio of the lateral length of the laser spot to the lateral length of the visible light image, α, the length d occupied by the lateral diameter of the laser spot is calculated. c =D c p, where D c =α·N is the number of pixels occupied by the lateral diameter of the laser spot; The laser beam divergence angle is Then, the target focal length value required by the corresponding laser illuminator is obtained according to the divergence angle of the laser beam.

5. The laser beam matching control method for low illumination reconnaissance as claimed in claim 3 or 4, characterized in that: The step three specifically includes: after completing the calculation of the target focal length value of the required laser illuminator, the control unit generates a corresponding adjustment instruction and sends it to the illuminator via wired or wireless communication, and the adjustment instruction includes the target focal length value parameter.

6. The laser beam matching control method for low-light reconnaissance as claimed in claim 5, characterized in that: The step 4 specifically includes: after the laser illuminator receives the adjustment instruction, the internal focusing mechanism starts working immediately, and the focal length and size of the laser spot are precisely adjusted by adjusting its optical elements.

7. The laser beam matching control method for low-light reconnaissance as claimed in claim 6, characterized in that: The step five specifically includes: after the laser illuminator completes the focal length adjustment of the laser beam, it will feed back its current spot data to the control unit. The spot data includes: the focal length and size of the laser spot. The control unit verifies whether the laser spot adjustment meets expectations by parsing these feedback data; if deviations are found, the control unit will further send a corrected adjustment instruction and execute step three to ensure that the final laser spot coverage effect is optimal.

8. The laser beam matching control method for low-illumination reconnaissance as claimed in claim 7, characterized in that: After zooming, the control unit obtains the focal length value of the current laser illuminator, and if there is a deviation from the calculated focal length value, the deviation data is sent out as a corrected adjustment instruction.

9. The laser beam matching control method for low-illumination reconnaissance as claimed in claim 7, characterized in that: The step six specifically includes: the control unit performs visual matching verification through the image captured in real time by the visible light TV, and analyzes the image captured by the visible light TV through the control unit to confirm whether the laser spot accurately covers the center of the field of view or the user-specified area. If a deviation in the laser spot coverage is found, the control unit will perform real-time optimization and adjustment to further accurately match the laser spot with the visible light TV field of view.

10. The laser beam matching control method for low-illumination reconnaissance as claimed in claim 9, characterized in that: The step seven specifically includes: displaying the status, adjustment process and results of the visible light television and laser illuminator to the user in real time through a friendly human-computer interaction interface. The user understands the current working status of the system through the interface and performs necessary manual intervention and adjustment.

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