A method of beam property probing
By combining a dual-channel high-intensity beam spot meter with mirror reflection attenuation and image grayscale analysis, the problems of resolution and accuracy in large spot measurement are solved, achieving efficient evaluation of laser beam characteristics, simplifying the optomechanical structure and expanding the measurement range.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINA JIUYUAN HI TECH EQUIP
- Filing Date
- 2026-04-27
- Publication Date
- 2026-06-05
Smart Images
Figure CN122149634A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of laser beam characteristic detection technology, and in particular to a method for detecting beam characteristics. Background Technology
[0002] The energy distribution characteristics of a light spot are a core evaluation indicator in the research and development and testing of lidar, optical detection systems, beam quality diagnostic equipment, etc. In the existing technology, there are two common methods for measuring large light spot distribution: one is the light spot imaging method, and the other is the array detection method.
[0003] For spot imaging methods, charge-coupled devices (CCDs) or complementary metal-oxide-semiconductor (CMOS) detectors are typically used. However, the target surface size of the detector is limited. When the size of the measured spot exceeds the effective photosensitive area of the detector, complete spot distribution data cannot be directly obtained. Therefore, existing solutions usually employ two types of indirect measurement methods: one is the imaging method, which projects a large spot onto a uniform reflective screen and then uses a detector to image the screen, indirectly inferring the spot distribution; the other is the beam-shrinking measurement method, which uses a complex beam-shrinking optical system to compress the spot size into the detector target surface before sampling and detection. Spot imaging methods have significant drawbacks. On the one hand, the imaging method relies on the uniformity of the reflective screen, and the absolute distribution of spot intensity needs to be calculated by extrapolating grayscale values, resulting in limited accuracy and making it difficult to meet the requirements of high-precision optical testing. On the other hand, beam-shrinking systems are complex in structure, have high debugging costs, and the beam-shrinking process may introduce beam distortion, affecting measurement reliability.
[0004] Furthermore, for large spot detection scenarios, the industry has also attempted to adopt large spot measurement array detector solutions. However, the resolution of this solution is far lower than that of traditional CCD / CMOS devices. To improve the resolution, the number of detector units per unit area needs to be significantly increased, which is extremely difficult to achieve under current semiconductor process conditions. At the same time, array detectors generally cannot support measurements under long-term high-power laser environments, and cannot meet the actual needs of related systems for high-precision and high-stability testing. Summary of the Invention
[0005] In view of this, the purpose of this application is to provide at least one method for detecting beam characteristics, which combines the reflection attenuation relationship of the beam by the mirror group, power sampling and image grayscale analysis to achieve high-resolution and high-precision evaluation of the characteristics of aurora light to the target.
[0006] This application mainly includes the following aspects: In a first aspect, embodiments of this application provide a beam characteristic detection method applied to a dual-channel high-intensity light spot detector. The dual-channel high-intensity light spot detector includes a spot detector housing, a diffuse reflection screen, optical components, a data acquisition component, and a control component. The diffuse reflection screen is fixed at the front end of the spot detector housing, and the optical components, data acquisition component, and control component are disposed inside the spot detector housing. The method includes: the optical components receiving a laser beam emitted by the system under test and reflecting the laser beam onto the diffuse reflection screen to form a diffuse reflection spot; the data acquisition component acquiring multiple sets of beam measurement data according to a preset acquisition cycle, each set of beam measurement data including a spot sampling image corresponding to the diffuse reflection screen acquired simultaneously and the transmitted laser power transmitted through the optical components; and the control component analyzing the laser beam based on the spot sampling image and transmitted laser power corresponding to each set of beam measurement data, utilizing the reflection attenuation relationship between the mirror groups to obtain the laser characteristic parameters corresponding to the system under test.
[0007] In one possible implementation, the optical components include an entrance window mirror, a primary reflector, and an exit window mirror. The entrance window mirror is fixed to the entrance window at the front end of the target spot instrument housing, forming a first preset angle with the vertical plane. Multiple optical sampling marks are set on the surface of the entrance window mirror. A diffuse reflection screen is set in the light path reflection direction of the entrance window mirror. The primary reflector is set at the rear end of the entrance window mirror. The primary reflector adopts a film structure with local high transmittance and overall high reflectivity. The primary reflector forms a second preset angle with the vertical plane. The exit window mirror is set on the top of the target spot instrument housing opposite to the primary reflector. The entrance window mirror receives the laser beam emitted by the system under test and reflects part of the laser beam to the diffuse reflection screen to form a diffuse reflection spot corresponding to the entire diffuse reflection screen. Marking spots corresponding to the optical sampling marks are formed inside the diffuse reflection spot. The entrance window mirror transmits part of the laser beam to the primary reflector. The primary reflector guides part of the received transmitted light to the atmosphere through the exit window mirror and transmits part of the transmitted light through a given central transmission area of the primary reflector to the data acquisition component.
[0008] In one possible implementation, for each set of beam measurement data acquired, the control component performs the following: extracting the number of marked spots from the spot sampling image corresponding to the set of beam measurement data, and determining whether the number of marked spots is equal to the number of optical sampling marks; if the number of marked spots is equal to the number of optical sampling marks, then the diffuse reflection spot sampling is complete, and the set of beam measurement data is retained; if the number of marked spots is not equal to the number of optical sampling marks, then the diffuse reflection spot sampling is incomplete, and the set of beam measurement data is discarded.
[0009] In one possible implementation, the laser characteristic parameters include a target beam quality index. The control component performs the following for each set of beam measurement data: grayscale restoration of the diffuse reflection spot to obtain a processed diffuse reflection spot; truncating the spot area of the processed diffuse reflection spot according to a given energy distribution, and performing circle fitting on the spot area to obtain the fitting radius corresponding to the given energy distribution circle; importing the fitting radius, the wavelength of the laser beam, the aperture of the system under test, and the focal length of the system under test into the beam quality formula to obtain the beam quality of the laser beam reflected by the diffuse reflection spot; and calculating the average beam quality of all beam measurement data, using the average beam quality as the target beam quality index.
[0010] In one possible implementation, the control component performs grayscale restoration of the diffuse reflection spot by: removing the marker spot from the diffuse reflection spot to form a removal area corresponding to the marker spot; using interpolation to fit the grayscale values at the outline of the removal area to obtain the fitted grayscale data corresponding to the removal area; and using the fitted grayscale data to fill the removal area to obtain the processed diffuse reflection spot.
[0011] In one possible implementation, after obtaining the fitting radius, the control component performs the following steps: restoring the fitting radius to the surface of the incident window mirror according to the angle between the diffuse reflection screen and the incident window mirror to obtain the fitting radius to be processed; restoring the fitting radius to be processed to the vertical position according to the first preset angle between the diffuse reflection screen and the vertical plane to obtain the restored fitting radius; and importing the restored fitting radius, the radius of the central region of the primary reflector, the wavelength corresponding to the laser beam, the aperture of the system under test, and the focal length of the system under test into the beam quality formula to obtain the beam quality of the laser beam reflected by the diffuse reflection spot.
[0012] In one possible implementation, the laser characteristic parameters further include a beam power index, wherein the control component determines the laser beam power index by: for each set of beam measurement data: analyzing the sampled image of the light spot to determine the grayscale data of the projection area corresponding to the center area of the primary reflector on the diffuse reflection screen; using the beam attenuation relationship within the optical components, determining the unit grayscale power within the projection area based on the transmitted laser power, the transmittance of the incident window mirror, the transmittance of the center area of the primary reflector, and the grayscale data of the projection area; multiplying the unit grayscale power by the target grayscale data corresponding to the diffuse reflection light spot after grayscale restoration processing to determine the real-time measured total power of the laser beam under that set of beam measurement data; and averaging the real-time measured total power corresponding to multiple sets of beam measurement data to determine the beam power index of the laser beam.
[0013] In one possible implementation, the control component determines the unit grayscale power within the projection area by: utilizing the beam attenuation relationship within the optical component, and based on the transmitted laser power, the transmittance of the incident window mirror, and the transmittance of the central region of the primary reflector, determining the calculated power of the projection area formed by the central region of the primary reflector on the diffuse reflection screen; and determining the ratio between the calculated power and the grayscale data of the projection area as the unit grayscale power within the projection area.
[0014] In one possible implementation, the data acquisition component includes a screen-capturing device and a power acquisition device. The screen-capturing device is located below the front of the incident window mirror, and the power acquisition device is located behind the primary reflector in the optical component. The screen-capturing device captures a light spot sampling image corresponding to the diffuse reflection screen and sends it to the control component; the power acquisition device captures the transmitted laser power and sends it to the control component.
[0015] In one possible implementation, the data acquisition component further includes a long-focal-length camera, which is arranged parallel to the incident direction of the laser beam. The long-focal-length camera acquires positioning images of the system under test and sends them to the host computer via the control component.
[0016] This application provides a beam characteristic detection method applied to a dual-channel high-intensity light target spot meter. The method includes: an optical component receiving a laser beam emitted by the system under test and reflecting the laser beam onto a diffuse reflection screen, forming a diffuse reflection spot on the screen; a data acquisition component acquiring multiple sets of beam measurement data according to a preset acquisition cycle, each set of beam measurement data including a sampled image of the spot corresponding to the diffuse reflection screen acquired simultaneously and the transmitted laser power transmitted through the optical component; and a control component analyzing the laser beam based on the sampled image of the spot and the transmitted laser power corresponding to each set of beam measurement data, utilizing the reflection attenuation relationship between the mirror groups to obtain the laser characteristic parameters corresponding to the system under test. This application combines the reflection attenuation relationship of the beam by the mirror groups, power sampling, and image grayscale analysis to achieve high-resolution and high-precision evaluation of the characteristics of aurora light reaching the target.
[0017] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description
[0018] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0019] Figure 1An axonometric view of a dual-channel high-intensity light target spot meter provided in an embodiment of this application is shown; Figure 2 A flowchart of a beam characteristic detection method provided in an embodiment of this application is shown; Figure 3 One of the cross-sectional views of a dual-channel high-intensity light target spot instrument provided in an embodiment of this application is shown; Figure 4 This illustration shows a schematic diagram of the internal positional structure of an optical component provided in an embodiment of this application; Figure 5 This is a second cross-sectional view of a dual-channel high-intensity light target spot instrument provided in an embodiment of this application. Detailed Implementation
[0020] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the drawings in this application are for illustrative and descriptive purposes only and are not intended to limit the scope of protection of this application. Furthermore, it should be understood that the schematic drawings are not drawn to scale. The flowcharts used in this application illustrate operations implemented according to some embodiments of this application. It should be understood that the operations in the flowcharts may not be implemented in sequence, and steps without logical contextual relationships may be reversed or implemented simultaneously. In addition, those skilled in the art, guided by the content of this application, may add one or more other operations to the flowcharts, or remove one or more operations from the flowcharts.
[0021] Furthermore, the described embodiments are merely some, not all, of the embodiments of this application. The components of the embodiments of this application described and illustrated herein can typically be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.
[0022] In the development of laser systems, there are two common methods for measuring large spot distribution: spot imaging and array detection.
[0023] The beam spot imaging method is widely used in low-power beam spot measurement. With the rapid development of CCD imaging technology, CCD-based beam quality measurement has been widely applied. The advantages of the beam spot imaging method are that it is non-contact, has a simple system structure, is easy to operate and use, and has high spatial resolution.
[0024] The advantages of array detection methods include direct measurement of the laser spot, high signal-to-noise ratio, wide range of motion, high sampling frequency, good real-time performance, and high temporal resolution. Based on their principles, array detection methods are classified into calorimetric array detection methods, photoelectric array detection methods, and calorimetric / photoelectric composite detection methods.
[0025] Because the target surface of CCD / CMOS detectors is small, it is impossible to directly measure the distribution characteristics of large light spots. Indirect measurement is usually performed by taking pictures or using beam-contraction measurement methods, which are suitable for measuring the relative distribution characteristics of light spots. The absolute distribution characteristics of light spot intensity need to be extrapolated from gray values, and the accuracy is difficult to guarantee.
[0026] The disadvantage of large spot measurement array detection method is that the resolution is much lower than that of CCD. If the resolution is to be improved, the number of detectors per unit area needs to be increased dramatically, which is not achievable with current technology. In addition, array detectors cannot support long-term high-power laser measurement and are difficult to cover the measurement requirements of related systems.
[0027] Based on this, embodiments of this application provide a beam characteristic detection method, which combines the reflection attenuation relationship of the beam by the mirror group, power sampling, and image grayscale analysis to achieve high-resolution and high-precision evaluation of the characteristics of aurora light to the target, as detailed below: Please see Figure 1 , Figure 1 An axonometric view of a dual-channel high-intensity light target spot instrument provided in an embodiment of this application is shown. Figure 1 As shown, the dual-channel high-intensity light spot detector provided in this embodiment includes a spot detector housing 1, a diffuse reflection screen 2, optical components (not shown in the figure), a data acquisition component (not shown in the figure), and a control component (not shown in the figure). The diffuse reflection screen 2 is fixed at the front end of the spot detector housing 1 and is adjustable. The optical components, data acquisition component, and control component are located inside the spot detector housing 1. Preferably, the diffuse reflection screen 2 serves as the sampling area for the light spot sampling image and has a high spherical reflectivity to ensure the accuracy of subsequent data measurement.
[0028] Please see Figure 2 , Figure 2 This paper illustrates a flowchart of a beam characteristic detection method provided in an embodiment of this application. The beam characteristic detection method provided in this application is applied to... Figure 1 The dual-channel high-intensity light target spot instrument shown is as follows: Figure 2 As shown, the method includes: S100: The optical component receives the laser beam emitted by the system under test and reflects the laser beam onto the diffuse reflection screen, forming a diffuse reflection spot on the screen.
[0029] S200: The data acquisition component acquires multiple sets of beam measurement data according to a preset acquisition cycle.
[0030] Preferably, each set of beam measurement data includes the light spot sampling image corresponding to the diffuse reflection screen acquired simultaneously and the transmitted laser power through the optical components.
[0031] S300 and the control component analyze the laser beam based on the spot sampling image and transmitted laser power corresponding to each group of beam measurement data, and obtain the laser characteristic parameters corresponding to the system under test by utilizing the reflection attenuation relationship between the beams between the mirror groups.
[0032] This invention provides a beam characteristic detection method for a dual-channel high-intensity laser beam speckle instrument. By analyzing the reflection attenuation relationship of the beam using a lens group, power sampling, and image grayscale analysis, it can measure the power of laser beams ranging from tens of thousands of watts to hundreds of thousands of watts and measure the real-time dynamic distribution of the laser. Furthermore, by post-processing the beam measurement data, the laser characteristic parameters of the laser beam emitted by the system under test can be calculated. These laser characteristic parameters reflect the target-reaching capability of the laser beam emitted by the system under test. The measurement time of the dual-channel high-intensity laser beam speckle instrument provided in this application can reach tens to hundreds of seconds, greatly shortening the time for evaluating the target-reaching capability of the laser beam emitted by the system under test. Moreover, by sampling the laser beam power locally (transmitted laser power) to infer the overall power index of the laser beam, the power limitation of the power acquisition device is removed, increasing the detection range of laser beam power (tens of thousands to hundreds of thousands of watts). It also utilizes the characteristics of beam speckle imaging to achieve high resolution and high measurement accuracy. Compared with the beam speckle imaging method, its optomechanical structure design is simpler, and it can achieve absolute intensity measurement. Compared with the array detection method, it has higher measurement resolution and can perform measurements for a longer period of time.
[0033] In a preferred embodiment, please refer to Figure 3 , Figure 3 This image shows one of the cross-sectional views of a dual-channel high-intensity light target spot meter provided in an embodiment of this application. Please refer to... Figure 4 , Figure 4 A schematic diagram of the internal structure of an optical component according to an embodiment of this application is shown. Please refer to... Figure 5 , Figure 5 This is a second cross-sectional view of a dual-channel high-intensity light target spot instrument provided in an embodiment of this application.
[0034] like Figures 3-5 As shown, the optical components include an entrance window mirror 3, a primary reflector 4, and an exit window mirror 5. The entrance window mirror 3 is fixed at the entrance window 6 at the front end of the target spot instrument chamber 1. The entrance window mirror 3 forms a first preset angle with the vertical plane (exemplarily 0°~60°). The surface of the entrance window mirror 3 has multiple optical sampling marks set by a special process.
[0035] The diffuse reflection screen 2 is set in the light path reflection direction of the incident window mirror 3, and the main reflector 4 is set at the rear end of the incident window mirror 3. The main reflector 4 adopts a film structure with local high transmittance and main high reflectivity to realize the detection of subsequent transmitted laser power. The main reflector 4 forms a second preset angle with the vertical plane (exemplarily 30°~60°). The main reflector 4 is fixed to the bottom of the target spot instrument chamber by the reflector frame 41. The exit window mirror 5 is set at the exit window 7 on the top of the target spot instrument chamber opposite to the main reflector 4.
[0036] The transmittance and reflectance of the incident window mirror 3, the transmittance and reflectance of the primary reflector 4, and the design of the optical sampling marks can be adapted to the actual measurement requirements. For example, given the given central transmission area of the primary reflector 4, the transmittance and reflectance setting of the given central transmission area can be determined according to the range of the power acquisition device. In addition, this application can use the entire given central transmission area as the sampling area of the power acquisition device, or a part of the given central transmission area as the sampling area of the power acquisition device. No specific limitation is made here.
[0037] In one specific embodiment, such as Figures 3-5 As shown, the incident window mirror 3 receives the laser beam emitted by the system under test and reflects part of the laser beam onto the diffuse reflection screen 2 to form a diffuse reflection spot corresponding to the entire diffuse reflection screen 2. The diffuse reflection spot contains a marker spot corresponding to the optical sampling mark. The incident window mirror 3 transmits part of the laser beam to the main reflector 4. The main reflector 4 sends part of the received transmitted light out to the atmosphere through the exit window mirror 5. The transmitted light passes through the given central transmission area T1 of the main reflector 4 to the data acquisition component, so that the corresponding transmitted laser power can be acquired by the data acquisition component.
[0038] Preferably, the data acquisition component includes a screen capturing device 8 and a power acquisition device 9. The screen capturing device 8 is located at the lower front of the incident window mirror 3 and is positioned opposite to the diffuse reflection screen 2. The power acquisition device 9 is positioned behind the main reflector 4. The screen capturing device 8 captures the light spot sampling image corresponding to the diffuse reflection screen 2 (specifically, the image corresponding to the diffuse reflection light spot) and sends it to the control component. The power acquisition device 9 captures the transmitted laser power and sends it to the control component.
[0039] In one specific embodiment, the camera selection for the screen-capturing device 8 is determined based on the ratio of the light intensity of the sampling area on the diffuse scattering screen 2 to the light intensity of the surrounding area of the sampling area. If the light intensity of the sampling area is extremely high, it may cause overexposure. In order to filter noise and achieve complete restoration of the diffuse reflection spot, a resolution of 9 to 12 bits is generally sufficient based on calculation and economic efficiency. The exposure time is adjustable. At the same time, in order to facilitate alignment with the power time axis, the screen-capturing device 8 has a manual shutter function. In addition, to avoid the influence of external natural light, the screen-capturing device 8 needs to use a near-infrared lens. For the incident laser wavelength, the lens needs to have high transmittance near 1µm in the near-infrared range. The output frame rate of the screen-capturing device 8 is greater than the power acquisition frequency of the power acquisition device 9, and is generally an integer multiple thereof, to facilitate time alignment.
[0040] In one specific embodiment, the power acquisition device 9 includes a power acquisition probe 91 and a power acquisition device 92, wherein the power acquisition device 92 uses the power acquisition probe 91 to acquire the transmitted laser power corresponding to the transmitted light of the main reflector 4 through the transmission window 93 and feeds it back to the control component.
[0041] The selection of the power acquisition device 9 is determined by the rated target power and power density of the laser beam and the size of the transmitted beam received by the main reflector. The design selects the target power of the laser beam to be 50% or more of the range of the power acquisition device 9 to ensure the accuracy of the measurement. The power acquisition device 9 is equipped with a water-cooled unit with equivalent cooling capacity, and the water-cooled unit is connected to the corresponding control equipment.
[0042] In a preferred embodiment, such as Figure 5 As shown, the data acquisition component also includes a long-focal-length photographic device 10, which is arranged parallel to the incident direction of the laser beam. In this application, the control component is connected to the host computer via a network cable or a wireless transmission module to realize data interaction with the host computer.
[0043] Preferably, the lens selection of the telephoto camera 10 needs to meet the following requirements: short focal length makes it easy to find the system under test, and long focal length can clearly image the system under test. Therefore, the telephoto camera 10 needs to be selected with electric zoom and electric magnification according to the distance of the system under test.
[0044] Before performing step S100, the method provided in this application further includes: The control component sends a shooting command to the telephoto camera 10. In response to the shooting command, the telephoto camera 10 acquires a positioning image of the system under test and sends it to the host computer via the control component. The host computer determines whether the dual-channel high-intensity light target spot instrument is axially aligned with the system under test based on the positioning image. If axial alignment is achieved, the host computer sends an axial alignment end command to the control component. In response to the axial alignment end command, the control component stops the telephoto camera 10 from shooting. If axial alignment is not achieved, the tester can adjust the position of the dual-channel high-intensity light target spot instrument and, after adjustment, send a shooting command to the telephoto camera 10 via the host computer and control component to allow the telephoto camera 10 to acquire the positioning image again until the axial alignment between the dual-channel high-intensity light target spot instrument and the system under test is completed.
[0045] After completing the axis alignment between the dual-channel high-intensity light spot instrument and the system under test, the dual-channel high-intensity light spot instrument executes steps S100 to S300.
[0046] In step S200, in one embodiment, the control component can simultaneously trigger the power acquisition device 9 to acquire power and trigger the screen capture device 8 to acquire the light spot sampling image through a preset acquisition cycle. In another embodiment, the operator can also manually issue sampling instructions for the light spot sampling image and transmitted laser power to the control component through the host computer. Here, there are no specific restrictions on the triggering method for acquiring beam measurement data.
[0047] In a preferred embodiment, the control component performs the following for each set of beam measurement data acquired: The number of marked spots is extracted from the spot sampling image corresponding to the beam measurement data. It is determined whether the number of marked spots is equal to the number of optical sampling marks. If the number of marked spots is equal to the number of optical sampling marks, the diffuse reflection spot sampling is complete, and the beam measurement data is retained. If the number of marked spots is not equal to the number of optical sampling marks, the diffuse reflection spot sampling is incomplete, and the beam measurement data is discarded.
[0048] In one specific embodiment, in order to ensure the accuracy of the laser characteristic parameters corresponding to the system under test obtained subsequently, this application performs quality screening on the collected multiple sets of beam measurement data by comparing the number of marked light spots with the number of optical sampling marks, so as to improve the accuracy of the subsequent laser characteristic parameters.
[0049] In a preferred embodiment, the laser characteristic parameters include a target beam quality index, and the control component performs the following for each set of beam measurement data: S3001. Perform grayscale restoration on the diffuse reflection spot to obtain the processed diffuse reflection spot.
[0050] S3002. Based on the given energy distribution, extract the light spot area of the processed diffuse reflection light spot, perform circle fitting on the light spot area, and obtain the fitting radius corresponding to the circle of the given energy distribution.
[0051] S3003. By importing the fitting radius, the wavelength corresponding to the laser beam, the aperture of the system under test, and the focal length of the system under test into the beam quality formula, the beam quality of the laser beam reflected by the diffuse reflection spot is obtained.
[0052] S3004. Calculate the average beam quality of all beam measurement data and use the average beam quality as the target beam quality index.
[0053] In one specific embodiment, step S3001 performed by the control component includes: The marked light spot is removed from the diffuse reflection light spot to form a removal area that corresponds one-to-one with the marked light spot. The gray value at the outline of the removal area is fitted by interpolation to obtain the fitted gray value data corresponding to the removal area. The removal area is filled with the fitted gray value data to obtain the processed diffuse reflection light spot.
[0054] In one example, the first grayscale data corresponding to the diffuse reflection spot is determined. And the second grayscale data corresponding to each marked spot. The fitted grayscale data corresponding to each elimination region is The final result is the target grayscale data corresponding to the diffuse reflection light after restoration. Represented as:
[0055] in, This represents the second grayscale data corresponding to the i-th marked spot. k represents the number of marked light spots. This represents the fitted grayscale data corresponding to the i-th marked spot. .
[0056] In a preferred embodiment, in step S3002 executed by the control component, the given energy distribution can be selected as 86.4%. The restored diffuse reflection spot is processed according to 86.4% of the energy distribution and fitted with a circle to obtain a circle with the given energy distribution and its corresponding fitting radius. .
[0057] Specifically, due to the angle between the incident window mirror and the incident laser beam, the horizontally incident laser beam will be distorted on the incident window mirror. Therefore, in order to increase the accuracy of subsequent feature analysis of the laser beam emitted by the system under test, the fitting radius needs to be adjusted. To perform the restoration, the fitting radius is obtained at the angle where the diffuse reflection screen 2 is located. Gradually restore to the vertical direction to resist the influence of angular distortion, specifically regarding the fitted radius. The restoration process includes: Based on the angle between the diffuse reflection screen and the incident window mirror, the fitted radius is restored to the surface of the incident window mirror to obtain the fitted radius to be processed. Based on the first preset angle between the diffuse reflection screen and the vertical plane, the fitted radius to be processed is restored to the vertical position to obtain the restored fitted radius.
[0058] In a preferred embodiment, in step S3003 performed by the control component, the beam quality formula is:
[0059] in, Indicates beam quality, This represents the reconstructed fitting radius corresponding to the diffuse reflection spot. Indicates the diameter of the system being tested. Indicates the wavelength of the laser beam. This indicates the focal length of the system being measured.
[0060] In step S3004 executed by the control component, the target beam quality index is determined using the following formula:
[0061] In this formula, This indicates the target beam quality index of the laser beam. Indicates the number of sets of beam measurement data. Indicates the first The restored fitting radius is obtained by solving the beam measurement data.
[0062] Preferably, the laser characteristic parameters also include beam power indicators. In a preferred embodiment, step S300 performed by the control component further includes: For each set of beam measurement data: S3005. Analyze the light spot sampling image to determine the grayscale data of the projection area on the diffuse screen corresponding to the central area of the main reflector.
[0063] S3006. Utilizing the beam attenuation relationship within the optical components, the unit grayscale power within the projection area is determined based on the transmitted laser power, the transmittance of the incident window mirror, the transmittance of the central region of the primary reflector, and the grayscale data of the projection area.
[0064] S3007. The product between the unit gray power and the target gray data corresponding to the diffuse reflection spot after gray restoration is determined as the real-time measured total power of the laser beam under this set of beam measurement data.
[0065] S3008. The average value of the real-time measured total power corresponding to multiple sets of beam measurement data is determined as the beam power index of the laser beam.
[0066] In step S3005 of the control component, the given central transmission area T1 of the primary reflector 4 (with a radius of...) Transmittance rate ) through the incident window mirror 3 (transmittance is The reflection onto the diffuse reflection screen forms an area of... Grayscale data is The projection area.
[0067] Step S3006 further includes: By utilizing the beam attenuation relationship within the optical components, and based on the transmitted laser power, the transmittance of the incident window mirror, and the transmittance of the central region of the primary reflector, the calculated power of the projection area formed by the central region of the primary reflector on the diffuse reflection screen is determined. The ratio between the calculated power of the projection area and its corresponding grayscale data is then defined as the unit grayscale power within the projection area.
[0068] In one specific embodiment, the calculated power of the projection area is determined by the following formula:
[0069] In this formula, This represents the unit grayscale power corresponding to the projected area. This represents the transmitted laser power collected by the power acquisition device corresponding to the projection area.
[0070] In another specific embodiment, the unit grayscale power of the projection area is determined by the following formula:
[0071] In step S3007, the real-time measured total power of the laser beam under each set of beam measurement data is determined by the following formula. :
[0072] In step S3008, due to the acquisition delay, the real-time measured total power is directly calculated using the measurement data from a single set of beams. As a measure of laser beam power, the error is relatively large. This application utilizes real-time measurement of total power from multiple sets of beam measurement data. The average value is used as the beam power index of the laser beam to improve the accuracy of the beam power index.
[0073] In one specific embodiment, the beam power index of the laser beam is determined by the following formula. :
[0074] Represents the real-time measured total power under the j-th beam measurement data. .
[0075] In a preferred embodiment, based on the concept of strong and weak light isolation, the target spot instrument chamber 1 of the dual-channel strong light target spot instrument of this application is further divided into a strong light chamber 11 and a weak light chamber 12. The strong light chamber 11 is sealed and can be filled with nitrogen to establish a dry and clean optical environment. Furthermore, the incident window mirror 3 and the main reflector 4 are set inside the strong light chamber 11. The weak light chamber 12 is equipped with a screen capture device 8, a power acquisition device 9 and its corresponding water-cooled unit, control components (not shown in the figure), and a long focal length photographic device 10. The weak light chamber 12 is also equipped with electrical connection lines, pipelines, and convection heat dissipation for the dual-channel strong light target spot instrument.
[0076] Preferably, considering the impact of solar radiation on the dual-channel high-intensity light target spot instrument during normal use, the exterior of the entire target spot instrument cabin 1 is designed with a corresponding heat insulation layer as needed. The heat insulation layer is made of non-metallic material and forms a certain air gap with the interior of the cabin to avoid the thermal impact of solar radiation on the electrical equipment inside the cabin.
[0077] In a preferred embodiment, the dual-channel high-intensity light target spot instrument also includes a power supply module. The power supply module can be an external power supply module located outside the target spot instrument chamber or an internal power supply module located inside the low-intensity light chamber 12. The power supply module is responsible for supplying power to the electrical equipment inside the target spot instrument chamber. The power supply module integrates a power conversion unit adapted to different electrical equipment, depending on the voltage and power consumption of each electrical equipment.
[0078] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems and devices described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here. In the several embodiments provided in this application, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of units is only a logical functional division; in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Another point is that the displayed or discussed mutual coupling or direct coupling or communication connection may be through some communication interfaces; the indirect coupling or communication connection of devices or units may be electrical, mechanical, or other forms.
[0079] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.
[0080] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.
[0081] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a processor-executable, non-volatile, computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.
[0082] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.
Claims
1. A method for detecting beam characteristics, characterized in that, This invention relates to a dual-channel high-intensity light target spot meter, which includes a target spot meter housing, a diffuse reflection screen, optical components, a data acquisition component, and a control component. The diffuse reflection screen is fixed to the front end of the target spot meter housing, while the optical components, data acquisition component, and control component are located inside the target spot meter housing. The method includes: The optical component receives the laser beam emitted by the system under test and reflects the laser beam onto the diffuse reflection screen, forming a diffuse reflection spot on the diffuse reflection screen; The data acquisition component acquires multiple sets of beam measurement data according to a preset acquisition cycle. Each set of beam measurement data includes the light spot sampling image corresponding to the diffuse reflection screen acquired simultaneously and the transmitted laser power transmitted through the optical component. The control component analyzes the laser beam based on the spot sampling image and transmitted laser power corresponding to each set of beam measurement data, and uses the reflection attenuation relationship between the mirror groups to obtain the laser characteristic parameters corresponding to the system under test.
2. The method according to claim 1, characterized in that, The optical components include an entrance window mirror, a primary reflector, and an exit window mirror. The entrance window mirror is fixed to the entrance window at the front end of the target spot instrument cabin and forms a first preset angle with the vertical plane. Multiple optical sampling marks are set on the surface of the entrance window mirror. The diffuse reflection screen is positioned along the optical path reflection direction of the incident window mirror. The main reflector is positioned at the rear end of the incident window mirror and employs a film structure with localized high transmittance and overall high reflectivity. The main reflector forms a second predetermined angle with the vertical plane. The exit window mirror is positioned on the top of the target spot instrument cabin, opposite the main reflector. The incident window mirror receives the laser beam emitted by the system under test and reflects part of the laser beam onto the diffuse reflection screen to form a diffuse reflection spot corresponding to the entire diffuse reflection screen. A marker spot corresponding to the optical sampling mark is formed inside the diffuse reflection spot. The incident window mirror transmits a portion of the laser beam to the main reflecting mirror; The primary reflector directs a portion of the received transmitted light to the atmosphere through the exit window mirror, and transmits a portion of the transmitted light through the given central transmission area of the primary reflector to the data acquisition component.
3. The method according to claim 2, characterized in that, The control component executes the following for each set of beam measurement data acquired: The number of marked spots is extracted from the spot sampling image corresponding to the set of beam measurement data, and it is determined whether the number of marked spots is equal to the number of optical sampling marks; If the number of marked light spots is equal to the number of optical sampling marks, then the diffuse reflection light spot sampling is complete, and the measurement data of this set of beams is retained; If the number of marked light spots is not equal to the number of optical sampling marks, it is determined that the diffuse reflection light spot sampling is incomplete, and the measurement data of that set of beams is discarded.
4. The method according to claim 2, characterized in that, The laser characteristic parameters include the target beam quality index. The control component performs the following for each set of beam measurement data: The diffuse reflection spot is restored to grayscale to obtain the processed diffuse reflection spot; Based on the given energy distribution, the light spot area of the processed diffuse reflection light spot is extracted, and the light spot area is circle-fitted to obtain the fitting radius corresponding to the circle of the given energy distribution. By importing the fitting radius, the wavelength corresponding to the laser beam, the aperture of the system under test, and the focal length of the system under test into the beam quality formula, the beam quality of the laser beam reflected by the diffuse reflection spot is obtained. The control component calculates the average beam quality of all beam measurement data and uses the average beam quality as the target beam quality index.
5. The method according to claim 4, characterized in that, The control component restores the grayscale of the diffuse reflection spot in the following manner: The marked light spot is removed from the diffuse reflection light spot to form a removal area that corresponds one-to-one with the marked light spot; Interpolation was used to fit the gray values at the outline of the eliminated area to obtain the fitted gray data corresponding to the eliminated area. The removed area is filled with the fitted grayscale data to obtain the processed diffuse reflection spot.
6. The method according to claim 4, characterized in that, After obtaining the fitting radius, the control component performs the following: Based on the angle between the diffuse reflection screen and the incident window mirror, the fitting radius is restored to the surface of the incident window mirror to obtain the fitting radius to be processed; According to the first preset angle between the diffuse reflection screen and the vertical plane, the fitting radius to be processed is restored to the vertical position to obtain the restored fitting radius; By incorporating the restored fitting radius, the radius of the central region of the primary reflector, the wavelength corresponding to the laser beam, the aperture of the system under test, and the focal length of the system under test into the beam quality formula, the beam quality of the laser beam reflected by the diffuse reflection spot is obtained.
7. The method according to claim 4, characterized in that, The laser characteristic parameters also include beam power indicators. The control component determines the beam power index in the following manner: For each set of beam measurement data: analyze the sampled image of the light spot to determine the grayscale data of the projection area on the diffuse reflection screen corresponding to the central area of the main reflector; Using the beam attenuation relationship within the optical component, and based on the transmitted laser power, the transmittance of the incident window mirror, the transmittance of the central region of the primary reflector, and the grayscale data of the projection area, the unit grayscale power within the projection area is determined. The product of the unit gray power and the target gray data corresponding to the diffuse reflection spot after gray restoration is determined as the real-time total measured power of the laser beam under this set of beam measurement data. The average value of the total real-time measured power corresponding to multiple sets of beam measurement data is determined as the beam power index of the laser beam.
8. The method according to claim 6, characterized in that, The control component determines the unit grayscale power within the projection area in the following manner: Using the beam attenuation relationship within the optical components, the calculated power of the projection area formed by the central region of the main reflector on the diffuse reflection screen is determined based on the transmitted laser power, the transmittance of the incident window mirror, and the transmittance of the central region of the main reflector. The ratio between the calculated power and the grayscale data of the projection area is determined as the unit grayscale power within the projection area.
9. The method according to claim 2, characterized in that, The data acquisition component includes a screen-capturing device and a power acquisition device. The screen-capturing device is located below the front of the incident window mirror, and the power acquisition device is located behind the primary reflector in the optical assembly. The screen-capturing device collects a light spot sampling image corresponding to the diffuse reflection screen and sends it to the control component; The power acquisition device acquires the transmitted laser power and sends it to the control component.
10. The method according to claim 1, characterized in that, The data acquisition component also includes a long-focal-length photographic device, which is arranged parallel to the incident direction of the laser beam. The telephoto lens captures the positioning image of the system under test and sends it to the host computer via the control component.