Laser beam divergence angle self-adaptive adjusting device and method based on retroreflection light spots

Abstract

The invention discloses a laser beam divergence angle self-adaptive adjusting device and method based on a retroreflection light spot, belongs to the technical field of laser wireless energy transmission, and solves the technical problem of mismatching of target coverage irradiated by the laser retroreflection light spot. The device comprises a laser emitting end, a control system, a rotary table and a target end, the laser transmitting end comprises a laser transmitter, a laser beam divergence angle adjusting lens and an imaging sensor; the imaging sensor is arranged on the laser transmitter; the rotary table comprises a rotary shaft and a rotary mirror surface; the rotary shaft is used for driving the mirror surface to rotate; the target end comprises a laser receiver and a retroreflection device, and the retroreflection device is arranged in the center of the laser receiver; the laser transmitter transmits a laser beam, the laser beam is transmitted to the rotating mirror surface after the divergence angle of the laser beam is adjusted by the laser beam divergence angle adjusting lens, and is reflected to the target end through the rotating mirror surface, and the target end redirects the received laser beam to the rotating mirror surface, and the laser beam is reflected to the photosensitive surface of the imaging sensor through the rotating mirror surface. The method is suitable for the technical field of laser wireless energy transmission for adjusting the divergence angle of the laser beam.

Description

Technical Field

[0001] The present invention belongs to the technical field of laser wireless energy transmission, and also relates to the technical field of laser wireless energy transmission for adjusting the divergence angle of a laser beam. Background Art

[0002] In the field of laser wireless power transmission (LWPT), lasers need to be precisely directed to a target receiver at a distant target end. For moving targets, the distance to the target receiver constantly changes, which can cause the spot size of a laser beam with a fixed beam divergence angle at the target to be too large or too small. If the beam divergence angle is too large, it will exceed the receiving range, resulting in energy waste. Low energy density may also cause the efficiency of the laser power converter (LPC) to decrease. If the beam divergence angle is too small, the energy is too concentrated, which may cause localized thermal effects on the surface of the laser power converter (LPC), making it difficult to reduce the thermal load, affecting its performance and lifespan, and reducing energy transmission efficiency. Existing technologies focus on precise tracking of the laser beam pointing, but research on matching target size and distance changes is insufficient, and there is a lack of adaptive adjustment of the laser beam divergence angle to achieve uniform laser beam illumination of the target. Summary of the Invention

[0003] In view of this, the present invention aims to solve the technical problem of coverage mismatch of the target illuminated by the laser retroreflection spot.

[0004] To achieve the above object, the present invention adopts the following technical solutions: The present invention proposes a device for adaptively adjusting the divergence angle of a laser beam based on a retroreflected light spot, the device comprising: Laser emitting end 1, control system 2, turntable 3 and target end 4; The laser emitting end 1 includes a laser emitter 11, a laser beam divergence adjustment lens 12 and an imaging sensor 13, wherein: The imaging sensor 13 is arranged on the laser emitter 11; The turntable 3 includes a rotating shaft 31 and a rotating mirror 32, and the rotating shaft 31 is used to drive the mirror 32 to rotate; The target end 4 includes a laser receiver 41 and a retroreflection device 42, and the retroreflection device 42 is arranged at the center of the laser receiver 41; The laser emitter 11 is used to emit a laser beam. After the laser beam divergence angle is adjusted by the laser beam divergence adjustment lens 12, the laser beam is emitted to the rotating mirror 32, and is reflected by the rotating mirror 32 to the target end 4. The target end 4 reflects the received laser beam back to the rotating mirror 32, and is reflected by the rotating mirror 32 to the photosensitive surface of the imaging sensor 13; The imaging sensor 13 converts the received laser signal into an electrical signal and transmits it to the control system 2; The control system 2 is configured to generate a control signal based on an electrical signal from the imaging sensor 13; the control signal includes a laser beam divergence control signal and a rotation axis control signal; the laser beam divergence control signal is sent to the laser beam divergence adjustment lens 12, and the rotation axis control signal is sent to the turntable 3; The turntable 3 is used to adjust the rotation angle of the rotating mirror 32 according to the received rotation axis control signal.

[0005] Furthermore, the retroreflection device 42 is used to receive the laser signal and reflect it back along its original path; the laser receiver 41 is used to transmit the received laser signal to the control system 2 via the rotating mirror 32 .

[0006] Furthermore, the laser signal captured by the imaging sensor 13 is the laser signal reflected by the turntable 3 .

[0007] Furthermore, the control system 2 is equipped with an image processing unit, which: Used to analyze the electrical signal from the imaging sensor 13 to form a spot image of the laser beam; Calculating the centroid position offset of the light spot image to obtain the laser beam pointing angle error; The optimal beam divergence angle is obtained according to the distance between the laser emitting end 1 and the target end 4, and the size of the laser receiver 4; The optimal beam spread angle generates a laser beam spread angle control signal.

[0008] Furthermore, the control system 2 is equipped with a control unit, which includes: A rotation axis control signal is generated according to the laser beam pointing angle error.

[0009] Furthermore, the laser beam divergence adjustment lens 21 is a complex layer structure, which is sequentially laminated along the laser incident direction: An incident layer substrate 211 , an incident layer electrode 212 , a liquid crystal layer 213 , an output layer electrode 214 and an output layer substrate 215 .

[0010] Furthermore, the laser beam divergence angle adjustment lens 12 receives the laser beam divergence angle control signal and adjusts the laser beam divergence angle through the liquid crystal layer 231 .

[0011] The present invention further proposes a method for adaptively adjusting the laser beam divergence angle based on the retroreflected light spot. The method is implemented based on the device of the present invention and includes: S1. The laser emitter 11 emits a laser beam; S2. The laser beam is emitted to the rotating mirror 32 after adjusting the divergence angle of the laser beam through the laser beam divergence adjustment lens 12; S3. The laser beam is reflected by the rotating mirror 32 to the target end 4 of the retroreflective device 42; S4. The laser beam is reflected back through the retroreflecting device 42 to the rotating mirror 32 and is incident on the photosensitive surface of the imaging sensor 13 via the rotating mirror 32; S5. The imaging sensor 13 converts the received laser signal into an electrical signal and transmits it to the control system 2; S6. The control system 2 generates a control signal based on the electrical signal from the imaging sensor 13; the control signal includes a laser beam divergence control signal and a rotation axis control signal; the laser beam divergence control signal is sent to the laser emitter 11, and the rotation axis control signal is sent to the turntable 3; S7. The turntable 3 adjusts the rotation angle of the rotating mirror 32 according to the received rotation axis control signal.

[0012] Furthermore, the control system 2 generates the laser beam divergence control signal in the following manner: Analyze the electrical signal from the imaging sensor 13 to form a spot image of the laser beam; Calculating the centroid position offset of the light spot image to obtain the laser beam pointing angle error; The optimal beam divergence angle is obtained according to the distance between the laser emitting end 1 and the target end 4, and the size of the laser receiver 4; The optimal beam spread angle generates a laser beam spread angle control signal.

[0013] Furthermore, the control system 2 generates the shaft control signal in the following manner: A rotation axis control signal is generated according to the laser beam pointing angle error.

[0014] The beneficial effects of the present invention are: (1) This device can dynamically adjust the laser beam divergence and direction through the combined structure of the laser emitting end, control system, turntable and target end. The imaging sensor at the laser emitting end captures the laser signal reflected from the target end. The control system processes and analyzes the laser signal, calculates the laser beam pointing angle error and the optimal beam divergence, and generates a laser beam divergence control signal and a rotation axis control signal respectively. The laser beam divergence adjustment lens adjusts the laser beam divergence according to the laser beam divergence control signal, and the turntable adjusts the direction of the rotating mirror according to the rotation axis control signal, so that the laser beam irradiation range matches the size of the laser receiver, adapts to the change of target distance, and avoids the laser beam spot on the receiving surface being too large or too small.

[0015] (2) The laser beam divergence adjustment lens described in this device includes a liquid crystal layer controlled by electrodes and used to dynamically adjust the laser beam divergence. This structure does not require mechanical moving parts and changes the angular distribution of the laser beam's emission direction by electrically controlling the arrangement of liquid crystal molecules, thereby achieving real-time adjustment of the laser beam divergence. The lens responds to the laser beam divergence control signal generated by the control system, so that the laser beam still covers the effective area of ​​the laser receiver under different distance conditions, meeting the demand for adaptive adjustment of the irradiation area in laser wireless energy transmission applications.

[0016] (3) The control system described in this device includes an image processing unit and a control unit, which are used to analyze the laser signal image and generate a control signal respectively. The image processing unit obtains the reflected light spot image collected by the imaging sensor, analyzes the light spot characteristics, calculates the center of mass position offset, and obtains the laser beam pointing angle error; and determines the optimal beam divergence angle based on the distance between the laser emitting end and the target end and the size of the laser receiver. The control unit generates a laser beam divergence control signal and a rotation axis control signal based on the above data, respectively, to achieve synchronous adjustment of the laser beam divergence angle and pointing direction, and maintain accurate irradiation of the laser beam on the target end.

[0017] (4) This device captures the image of the reflected light spot based on the imaging sensor, analyzes the light spot characteristics through the image processing unit, calculates the laser beam pointing angle error and the optimal beam divergence angle, and generates corresponding control signals by the control unit to achieve adaptive adjustment of the laser beam divergence angle. When the distance to the target end becomes farther, the control system increases the beam divergence angle to prevent the light spot from being smaller than the receiving surface of the target end; when the distance becomes closer, the beam divergence angle is reduced to avoid the energy being concentrated on a part of the receiving surface of the target end. The entire adjustment process relies on the characteristics of the reflected light spot for real-time feedback control, so that the laser beam continues to cover the surface of the laser receiver under the condition of changing distance, effectively adapting to the beam divergence matching requirements caused by the target movement during the laser wireless energy transmission process.

[0018] The present invention is applicable to the technical field of laser wireless energy transmission for adjusting the divergence angle of a laser beam through a laser spot. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings, which constitute part of the present invention, are provided to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are provided to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings: Figure 1This is a schematic diagram of a device for adaptively adjusting the laser beam divergence angle based on retroreflected light spots, as described in Specific Embodiment 1. The following figures are referenced: laser emitting end 1, laser emitter 11, laser beam divergence adjustment lens 12, imaging sensor 13, control system 2, turntable 3, rotating mirror 31, rotating shaft 32, target end 4, laser receiver 41, and retroreflective device 42. The red solid line in the figure represents the optical path of the laser beam after adjustment of the laser beam divergence angle by the laser beam divergence adjustment lens 12, reflected from the rotating mirror 31, and then directed to the retroreflective device 42. The blue solid line represents the optical path of the laser beam reflected back to the imaging sensor 13. The red dashed line represents the maximum divergence angle range of the laser beam reflected from the rotating mirror 31 that can be received by the retroreflective device 42.

[0020] Figure 2 Schematic diagram of the laser beam divergence adjustment lens structure described in Embodiment 7. Reference numerals in the figure include: incident layer substrate 211, incident layer electrode 212, liquid crystal layer 213, exit layer electrode 214, and exit layer substrate 215; arrows indicate the transmission direction of optical signals. DETAILED DESCRIPTION

[0021] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely explain the technical solutions in the embodiments of the present invention. It should be noted that the embodiments of the present invention and the features therein can be combined with each other in the absence of conflict, and the embodiments described are only part of the embodiments of the present invention, not all of the embodiments.

[0022] Specific embodiment 1, the laser beam divergence adaptive adjustment device based on the retroreflected light spot described in this embodiment includes: Laser emission end, control system, turntable and target end; The laser emitting end includes a laser emitter, a laser beam divergence adjustment lens and an imaging sensor, wherein: The imaging sensor is arranged on the laser emitter; The turntable comprises a rotating shaft and a rotating mirror, wherein the rotating shaft is used to drive the mirror to rotate; The target end includes a laser receiver and a retroreflector, wherein the retroreflector is arranged at the center of the laser receiver; A laser emitter is used to emit a laser beam. After the laser beam has its divergence angle adjusted by a laser beam divergence adjustment lens, the laser beam is emitted to a rotating mirror surface, which is then reflected by the rotating mirror surface to a target end. The target end then reflects the received laser beam back to the rotating mirror surface, which is then reflected by the rotating mirror surface to a photosensitive surface of an imaging sensor. The imaging sensor converts the received laser signal into an electrical signal and transmits the electrical signal to the control system; The control system is configured to generate a control signal based on an electrical signal from the imaging sensor; the control signal includes a laser beam divergence control signal and a rotation axis control signal; the laser beam divergence control signal is sent to the laser beam divergence adjustment lens, and the rotation axis control signal is sent to the turntable; The turntable is used to adjust the rotation angle of the rotating mirror according to the received rotation axis control signal.

[0023] In this embodiment, the device achieves dynamic adjustment of the laser beam divergence and pointing direction through an integrated structure of a laser emitting end, a control system, a turntable, and a target end. The laser emitting end emits a laser beam, and the imaging sensor is arranged coaxially or near-axially with the laser emitter to receive and image the laser spot reflected from the target end's retroreflector. The sensor is capable of capturing the retroreflected spot signal in real time. The control system analyzes the signal and calculates the optimal beam divergence and pointing error to generate a corresponding control signal. The turntable adjusts the mirror angle according to the control signal to ensure that the laser beam accurately illuminates the target end. At the same time, the laser beam divergence adjustment lens dynamically adjusts the beam divergence so that the spot always matches the size of the laser receiver, avoiding illumination mismatch problems caused by distance changes. Specific embodiment 2: This embodiment further limits the retroreflector device described in specific embodiment 1. The retroreflector is used to receive the laser signal and reflect it along its original path; the laser receiver is used to reflect the received laser signal via a rotating mirror to the laser beam divergence adjustment lens.

[0024] This embodiment further limits the target end described in the first embodiment. In this embodiment, the retroreflective device is located at the center of the laser receiver at the target end to ensure that the retroreflected light spot can be accurately captured by the imaging sensor. This structural design optimizes the stability of the retroreflected signal, enables the control system to more accurately analyze the light spot characteristics, and improves the accuracy of laser beam adjustment.

[0025] Specific embodiment three: This embodiment further limits the imaging sensor described in specific embodiment one. The laser signal captured by the imaging sensor is the laser signal reflected by the turntable.

[0026] This embodiment further defines the imaging sensor described in Specific Embodiment 1. In this embodiment, the imaging sensor utilizes a high-resolution imaging device, such as a CMOS or CCD camera, to capture the laser signal reflected from the turntable. This sensor assists in monitoring and identifying key aspects of the laser propagation process, providing accurate data for subsequent processing such as spot image analysis, laser beam divergence adjustment, and direction correction.

[0027] Specific embodiment 4, this embodiment further defines the image processing unit of the control system described in specific embodiment 1, and the image processing unit includes: Analyzing the light spot characteristics of the laser signal received by the imaging sensor to form a light spot image; Calculating the centroid position offset of the light spot image to obtain the laser beam pointing angle error; Obtain the optimal beam divergence angle based on the distance between the laser transmitter and the target, and the size of the laser receiver; The optimal beam spread angle generates a laser beam spread angle control signal.

[0028] This embodiment further defines the image processing unit described in Specific Embodiment 1. In this embodiment, the image processing unit analyzes the characteristics of the light spot, calculates the center of mass offset to determine the laser beam pointing error, and calculates the optimal beam divergence angle in combination with the distance to the target end and the size of the receiver, thereby optimizing the adjustment of the laser irradiation and ensuring that the light spot always covers the laser receiver. The image processing unit obtains the laser beam pointing angle error and the optimal beam divergence angle, and uses the optimal beam divergence angle to generate a corresponding control signal to achieve control of the laser beam divergence angle and laser beam pointing. By adjusting the laser beam irradiation parameters in real time, controlling the laser beam divergence angle and laser beam pointing, it is ensured that the laser beam always remains directed to the target end receiver under different distance and direction conditions, meeting the dynamic control requirements for energy coverage accuracy in laser wireless energy transmission.

[0029] Specific embodiment 5, this embodiment further defines the control unit of the control system described in specific embodiment 1, the control system is equipped with a control unit, and the control unit includes: A rotation axis control signal is generated according to the laser beam pointing angle error.

[0030] This embodiment further limits the control system described in the specific embodiment one. In this embodiment, the control unit generates a rotation axis control signal for controlling the rotation axis of the turntable and adjusting the direction of the rotating mirror of the turntable so that the laser beam propagates toward the target end and the laser spot covers the target end area.

[0031] Specific embodiment 6: This embodiment further defines the laser beam divergence adjustment lens described in specific embodiment 1. The laser beam divergence adjustment lens is a complex layer structure, which is sequentially laminated along the laser incident direction. Incident layer substrate, incident layer electrode, liquid crystal layer, exiting layer electrode and exiting layer substrate.

[0032] This embodiment further limits the laser beam divergence adjustment lens described in the specific embodiment one. In this embodiment, the laser beam divergence adjustment lens realizes the electronic control adjustment of the laser beam output angle through a multi-layer structure including an incident layer substrate, a liquid crystal layer, and an electrode layer. This design can optimize the beam divergence in real time according to the control signal to ensure that the spot size matches the size of the laser receiver.

[0033] Specific embodiment seven: This embodiment further limits the laser beam divergence angle adjustment lens described in specific embodiment six. The laser beam divergence angle adjustment lens receives the laser beam divergence angle control signal and adjusts the laser beam divergence angle through the liquid crystal layer.

[0034] This embodiment further defines the laser beam divergence adjustment lens described in Specific Embodiments 7 or 5. In this embodiment, the lens utilizes a liquid crystal layer structure. Voltage applied to the incident and exit electrodes modulates the arrangement of the liquid crystal molecules, thereby dynamically adjusting the laser beam divergence. This lens structure avoids traditional mechanical focusing mechanisms and instead uses voltage-regulated liquid crystal arrangement to control the laser beam's divergence angle. It offers fast response speed and high precision, enabling real-time optimization of the beam divergence based on control signals to ensure that the spot size matches the laser receiver's dimensions. The liquid crystal layer, controlled by electrodes, dynamically adjusts the laser beam's divergence angle. This structure eliminates the need for mechanical moving parts and achieves real-time adjustment of the laser beam's divergence angle by electrically controlling the arrangement of the liquid crystal molecules to alter the angular distribution of the laser beam's exit direction. The lens responds to the laser beam divergence control signal generated by the control system, ensuring that the laser beam still covers the effective area of ​​the laser receiver at varying distances, thus meeting the need for adaptive adjustment of the irradiation area in laser wireless energy transmission applications.

[0035] Specific embodiment eight, the method for adaptively adjusting the laser beam divergence angle based on the retroreflected light spot described in this embodiment is implemented based on any device described in specific embodiments one to seven, and the method includes: S1. The laser transmitter emits a laser beam; S2. The laser beam is emitted to the rotating mirror after the laser beam divergence adjustment lens adjusts the divergence angle; S3. The laser beam is reflected by the rotating mirror to the target end; S4. The laser beam is reflected back through the target end to the rotating mirror and then reflected by the rotating mirror to the photosensitive surface of the imaging sensor; S5. The imaging sensor converts the received laser signal into an electrical signal and transmits it to the control system; S6. The control system generates a control signal based on the electrical signal from the imaging sensor; the control signal includes a laser beam divergence control signal and a rotation axis control signal; the laser beam divergence control signal is sent to the laser beam divergence adjustment lens, and the rotation axis control signal is sent to the turntable; S7. The turntable adjusts the rotation angle of the rotating mirror according to the received rotation axis control signal.

[0036] In this embodiment, this method uses an imaging sensor to capture laser signals. Combined with control signals generated by a control system, this method drives a turntable to adjust the emission direction and receive reflected laser light, enabling real-time monitoring and analysis of the reflected light spot. The control system then uses a laser beam divergence adjustment lens to adjust the laser beam divergence, thereby achieving adaptive matching between the laser beam coverage and the receiving surface of the target laser receiver. This improves laser energy transmission efficiency and supports stable operation in scenarios with moving targets, ensuring that the beam spot always accurately covers the target receiver, effectively resolving the illumination mismatch problem caused by varying target distance. Specific embodiment 9: This embodiment further limits the control system described in specific embodiment 8. The method for generating the laser beam divergence control signal by the control system is as follows: Analyze the electrical signal from the imaging sensor to form a spot image of the laser beam; Calculating the centroid position offset of the light spot image to obtain the laser beam pointing angle error; Obtain the optimal beam divergence angle based on the distance between the laser transmitter and the target, and the size of the laser receiver; The optimal beam spread angle generates a laser beam spread angle control signal.

[0037] This embodiment further limits the image processing unit described in the specific embodiment 1. In this embodiment, the laser beam pointing angle error and the optimal beam divergence angle are obtained through the image processing unit, and the control unit is used to generate corresponding control signals to realize the control of the laser beam divergence angle and the laser beam pointing.

[0038] The image processing unit analyzes the size, shape, intensity distribution and other characteristics of the retroreflected light spot image.

[0039] Light spot centroid position: used to calculate pointing deviation; Spot diameter: used to calculate the target end distance and spot coverage; Beam spot circularity: evaluates beam quality and medium influence; Energy distribution uniformity: Calculate the standard deviation of pixel intensity and energy concentration of the spot to avoid local overheating; Peak intensity and average intensity of the spot: evaluate the energy density.

[0040] The distance to the target end is calculated mainly based on the size of the image of the retroreflection spot on the imaging sensor. Required characteristics: Retroreflection spot diameter; Required parameters: Aperture of the retroreflection device and the effective focal length of the imaging system Calculation formula:

[0041] And combined with the laser receiver size information, the diameter or length and width of the effective photosensitive surface area of ​​the target end laser power converter (LPC) is obtained.

[0042] Determine the current beam divergence angle The current beam divergence angle is obtained through the control parameters of the liquid crystal lens. There is a pre-calibrated database or function inside the system, which maps the precise relationship between the control signal (such as voltage) applied to the liquid crystal lens and the laser beam divergence angle it produces. Therefore, when the system issues a control instruction, it already knows the current beam divergence angle setting value. Whether it is optimal (evaluation of coverage, overflow) judgment conditions: 1 High coverage: the ratio of the coverage area of ​​the laser spot on the laser receiver at the target end to the total area of ​​the laser receiver, the ideal target is >90%; 2 Low overflow rate: the energy of the light spot beyond the range of the laser receiver should be as little as possible, the ideal target is <10%; and calculate the parameters required for the target optimal beam divergence value: calculated target distance , the effective diameter of the receiver is known Calculation formula: ; Calculate the laser beam pointing angle error based on the centroid position offset of the retroreflected spot imaging The pixel distance deviation between the centroid coordinates of the retroreflected light spot image and the center of the optical axis of the imaging sensor (i.e., the calibrated image center point). This offset directly reflects the deviation between the laser beam pointing to the target end center.

[0043] Calculated by trigonometric function. Required parameters: center of mass position deviation , the physical size of a unit pixel of an imaging sensor (μm / pixel), effective focal length of the imaging system The calculation formula is:

[0044] At long distances and small angles, it can be simplified to .

[0045] It is generated by querying the pre-calibrated "beam divergence angle-control signal" database or function. The process is: input the calculated optimal beam divergence angle , obtained through a pre-calibrated database or function The corresponding control signal value (e.g., voltage) is sent to the driver of the laser beam divergence adjustment lens. Alternatively, a PID controller can be used, with the input error value used to generate a control signal. This signal is then sent to the laser beam divergence adjustment lens to adjust the beam divergence of the emitted laser.

[0046] Specific embodiment 10: This embodiment further limits the control unit described in specific embodiment 8. The method for the control system to generate the shaft control signal is: A rotation axis control signal is generated according to the laser beam pointing angle error.

[0047] This embodiment further limits the control system described in the specific embodiment one. In this embodiment, the control unit generates a control instruction, which is a shaft control signal. The shaft control signal is used to adjust the shaft of the turntable, and the direction of the rotating mirror of the turntable is adjusted by the shaft to make the laser beam propagate toward the target end, so that the laser spot covers the target end area.

Claims

1. A laser beam divergence adaptive adjustment device based on retroreflected light spot, characterized in that: The device comprises: Laser emitting end (1), control system (2), turntable (3) and target end (4); The laser emitting end (1) comprises a laser emitter (11), a laser beam divergence adjustment lens (12) and an imaging sensor (13), wherein: The imaging sensor (13) is arranged on the laser emitter (11); The turntable (3) comprises a rotating shaft (31) and a rotating mirror (32), wherein the rotating shaft (31) is used to drive the mirror (32) to rotate; The target end (4) comprises a laser receiver (41) and a retroreflection device (42), wherein the retroreflection device (42) is arranged at the center of the laser receiver (41); A laser emitter (11) is used to emit a laser beam. The laser beam is emitted to a rotating mirror (32) after its divergence angle is adjusted by a laser beam divergence adjustment lens (12). The laser beam is reflected to a target end (4) by the rotating mirror (32). The target end (4) reflects the received laser beam back to the rotating mirror (32). The rotating mirror (32) reflects the laser beam to a photosensitive surface of an imaging sensor (13). The imaging sensor (13) converts the received laser signal into an electrical signal and transmits the electrical signal to the control system (2); The control system (2) is used to generate a control signal based on an electrical signal from an imaging sensor (13); the control signal includes a laser beam divergence control signal and a rotation axis control signal; the laser beam divergence control signal is sent to a laser beam divergence adjustment lens (12), and the rotation axis control signal is sent to a turntable (3); The turntable (3) is used to adjust the rotation angle of the rotating mirror (32) according to a received rotation axis control signal.

2. The laser beam divergence adaptive adjustment device based on retroreflected light spot according to claim 1, characterized in that: The retroreflection device (42) is used to receive the laser signal and reflect it back along its original path; the laser receiver (41) is used to transmit the received laser signal to the control system (2) via the rotating mirror (32).

3. The laser beam divergence adaptive adjustment device based on retroreflected light spot according to claim 1, characterized in that: The laser signal captured by the imaging sensor (13) is the laser signal reflected by the turntable (3).

4. The laser beam divergence adaptive adjustment device based on retroreflected light spot according to claim 1, characterized in that: The control system (2) is equipped with an image processing unit, wherein the image processing unit: Used to analyze the electrical signal from the imaging sensor (13) to form a spot image of the laser beam; Calculating the centroid position offset of the light spot image to obtain the laser beam pointing angle error; Obtaining an optimal beam divergence angle according to the distance between the laser emitting end (1) and the target end (4), and the size of the laser receiver (4); The optimal beam spread angle generates a laser beam spread angle control signal.

5. The laser beam divergence adaptive adjustment device based on retroreflected light spot according to claim 4, characterized in that: The control system (2) is equipped with a control unit, which includes: A rotation axis control signal is generated according to the laser beam pointing angle error.

6. The laser beam divergence adaptive adjustment device based on retroreflected light spot according to claim 1, characterized in that: The laser beam divergence adjustment lens (21) is a complex layer structure, which is sequentially arranged along the laser incident direction: An incident layer substrate (211), an incident layer electrode (212), a liquid crystal layer (213), an exit layer electrode (214) and an exit layer substrate (215).

7. The laser beam divergence adaptive adjustment device based on retroreflected light spot according to claim 6, characterized in that: The laser beam divergence angle adjustment lens (12) receives the laser beam divergence angle control signal and adjusts the laser beam divergence angle through the liquid crystal layer (231).

8. A method for adaptively adjusting the laser beam divergence angle based on a retroreflected light spot, characterized in that: The method is implemented based on any one of the devices described in claims 1 to 7, and the method includes: S1. A laser transmitter (11) emits a laser beam; S2. The laser beam is emitted to the rotating mirror (32) after adjusting the divergence angle of the laser beam through the laser beam divergence adjustment lens (12); S3. The laser beam is reflected by the rotating mirror (32) to the retroreflective device (42) at the target end (4); S4. The laser beam is reflected back through the retroreflective device (42) to the rotating mirror (32), and is incident on the photosensitive surface of the imaging sensor (13) through the rotating mirror (32); S5. The imaging sensor (13) converts the received laser signal into an electrical signal and transmits it to the control system (2); S6. The control system (2) generates a control signal based on the electrical signal from the imaging sensor (13); the control signal includes a laser beam divergence control signal and a rotation axis control signal; the laser beam divergence control signal is sent to the laser emitter (11), and the rotation axis control signal is sent to the turntable (3); S7. The turntable (3) adjusts the rotation angle of the rotating mirror (32) according to the received rotation axis control signal.

9. The method for adaptively adjusting the laser beam divergence angle based on the retroreflected light spot according to claim 8, characterized in that: The control system (2) generates a laser beam divergence control signal in the following manner: Analyzing the electrical signal from the imaging sensor (13) to form a spot image of the laser beam; Calculating the centroid position offset of the light spot image to obtain the laser beam pointing angle error; Obtaining an optimal beam divergence angle according to the distance between the laser emitting end (1) and the target end (4), and the size of the laser receiver (4); The optimal beam spread angle generates a laser beam spread angle control signal.

10. The method for adaptively adjusting the laser beam divergence angle based on the retroreflected light spot according to claim 8, characterized in that: The control system (2) generates a shaft control signal in the following manner: A rotation axis control signal is generated according to the laser beam pointing angle error.

Images