Angle detection method, device and equipment and readable storage medium
Through local calibration and cross-correlation theory, combined with the target speckle pattern and the calibrated speckle image, the problem of complex preparation work and low accuracy of existing angle detection methods is solved, and more efficient and accurate angle detection is achieved.
Patent Information
- Application Number
- CN202510192397.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-20
- Publication Date
- 2025-05-27
AI Technical Summary
The preparation work of existing angle detection methods is complex and has low accuracy, making it difficult to improve the accuracy of angle detection on the basis of reducing the preparation workload.
The local calibration method is adopted and combined with the cross-correlation theory, the incidence angle of the target incident light is determined by measuring the target speckle pattern corresponding to the target incident light within the measurement range and the calibrated speckle image.
On the basis of reducing the preparation workload, the accuracy of angle detection is significantly improved, and more efficient angle detection is achieved.
Smart Images
Figure CN120044001A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the technical field of angle detection, and particularly to an angle detection method, device, equipment and readable storage medium. Background Art
[0002] A scattering medium is a substance that can scatter light. Multiple scattering of light in a scattering medium (such as white paint, paper, and biological tissue) randomizes the propagation of light, disrupts the spatial information carried by the light beam, and forms a random granular pattern, i.e., speckle, during the projection process.
[0003] Within the effective range of angular memory, there is a strong correlation between the speckles formed by light beams with different incident angles after passing through the scattering medium. Its output structure remains unchanged and only lateral movement occurs. In order to determine the magnitude of the incident angle, the traditional angle detection method is to record the speckles corresponding to all incident angles within the effective range of angular memory, and then determine the incident angle of the light beam actually corresponding to the measured speckle through a look-up table, which leads to the problems of overly complex preparation work and low detection accuracy.
[0004] Therefore, how to improve the accuracy of angle detection on the basis of reducing the preparation workload is an urgent problem for those skilled in the art. Summary of the Invention
[0005] Based on the above problems, this application provides an angle detection method, device, equipment and readable storage medium, which adopts a local calibration method, combines the cross-correlation theory, and determines the incident angle of the target incident light according to the target speckle pattern corresponding to the target incident light within the measurement range and the calibrated speckle image, thereby improving the accuracy of angle detection on the basis of reducing the preparation workload.
[0006] In a first aspect, an embodiment of this application provides an angle detection method, and the method includes:
[0007] Obtain a target speckle pattern corresponding to a target incident light within a first measurement range;
[0008] Determine a first correlation value between the target speckle pattern and a first speckle pattern;
[0009] Determine position information corresponding to the target incident light based on the first correlation value;
[0010] Determine a second correlation value between the target speckle pattern and a second speckle pattern; the first speckle pattern and the second speckle pattern respectively calibrate the incident angles of the corresponding optical paths;
[0011] Determine the incident angle of the target incident light based on the second correlation value and the position information.
[0012] Optionally, determining the position information corresponding to the target incident light based on the first correlation value includes:
[0013] Based on the first correlation value, using a correlation coefficient function to determine a first angle and a second angle between the target incident light and a first incident light corresponding to the first speckle pattern;
[0014] The correlation coefficient function is:
[0015]
[0016] In the formula is the value of the correlation coefficient, k is the wave vector, L is the thickness of the scattering medium, is the angle between the incident angle of the reference speckle and the incident angle of the target speckle.
[0017] Optionally, determining the incident angle of the target incident light based on the second correlation value and the position information includes:
[0018] Determining the maximum value in the second correlation value;
[0019] According to the maximum value, determining a target angle corresponding to the target incident light from the first angle and the second angle;
[0020] Determining the incident angle of the target incident light based on the target angle.
[0021] Optionally, the method further includes:
[0022] Based on the type and thickness of the scattering medium, determining the range of the angular optical memory effect;
[0023] Based on the range, splicing multiple segments of effective memory effects to obtain a corresponding first measurement range.
[0024] Optionally, the method further includes:
[0025] Based on the multiple segments of effective memory effects and the correlation coefficient function, calibrating each peak and valley in the function image; there are at least two peaks, the valleys correspond to the peaks, and each peak corresponds to two adjacent valleys;
[0026] The speckle pattern corresponding to the peak is the first scattering speckle pattern; the speckle image corresponding to the valley is the second speckle pattern.
[0027] Optionally, determining the first correlation value between the target speckle pattern and the first speckle pattern includes:
[0028] Perform cross-correlation processing on the target speckle pattern and each of the first speckle patterns respectively, and obtain candidate correlation values corresponding to the respective first speckle patterns;
[0029] Compare the magnitudes of the candidate correlation values, and use the candidate correlation value with the largest value as the first correlation value.
[0030] Optionally, the method further includes:
[0031] Determine the first speckle pattern corresponding to the target speckle pattern according to the candidate correlation value with the largest value;
[0032] Based on the first speckle pattern, determine the second speckle pattern corresponding to the target speckle pattern.
[0033] In a second aspect, an embodiment of the present application provides an angle detection device, including:
[0034] An acquisition module, configured to acquire a target speckle pattern corresponding to a target incident light within a first measurement range;
[0035] A first determination module, configured to determine a first correlation value between the target speckle pattern and a first speckle pattern;
[0036] A second determination module, configured to determine position information corresponding to the target incident light based on the first correlation value;
[0037] A third determination module, configured to determine a second correlation value between the target speckle pattern and a second speckle pattern; the first speckle pattern and the second speckle pattern respectively calibrate corresponding optical path incident angles;
[0038] A fourth determination module, configured to determine the incident angle of the target incident light based on the second correlation value and the position information.
[0039] In a third aspect, an embodiment of the present application provides an angle detection device, including:
[0040] A memory, configured to store a computer program;
[0041] A processor, configured to implement the steps of the angle detection method as described above when executing the computer program.
[0042] In a fourth aspect, an embodiment of the present application provides a readable storage medium, on which a computer program is stored, and the computer program, when executed by a processor, implements the steps of the angle detection method as described above.
[0043] As can be seen from the above technical solutions, compared with the prior art, the present application has the following advantages:
[0044] This application first obtains the target speckle pattern corresponding to the target incident light within the first measurement range. Then, it determines the first correlation value between the target speckle pattern and the first speckle pattern, and determines the position information corresponding to the target incident light based on the first correlation value. Finally, it determines the second correlation value between the target speckle pattern and the second speckle pattern, and determines the incident angle of the target incident light based on the second correlation value and the position information. Among them, the first speckle pattern and the second speckle pattern respectively calibrate the incident angles of the corresponding optical paths. In this way, by using the method of local calibration and combining the cross-correlation theory, the incident angle of the target incident light is determined according to the target speckle pattern corresponding to the target incident light within the measurement range and the calibrated speckle images, thereby improving the accuracy of angle detection on the basis of reducing the preparation workload. Description of the Drawings
[0045] Figure 1 Schematic diagram of an experimental device provided by an embodiment of this application;
[0046] Figure 2 Flowchart of an angle detection method provided by an embodiment of this application;
[0047] Figure 3 Experimental effect diagram provided by an embodiment of this application;
[0048] Figure 4 Schematic structural diagram of an angle detection device provided by an embodiment of this application. Detailed Embodiment
[0049] As described above, the existing angle detection method is to gradually change the incident angle of the incident light according to the minimum resolution for identifying different speckles before detection, record the corresponding speckles during this process, and finally obtain a complete look-up table of the correspondence between speckles and incident angles. When performing angle detection later, the target speckle can be compared one by one with the speckles generated previously in the look-up table, so as to find the incident angle of the incident light corresponding to the target speckle. In this way, global calibration is required, and the preparation work is too complicated, and it is easy to make mistakes during the comparison process, resulting in the problems of overly complicated preparation work and low detection accuracy.
[0050] To solve the above problems, an embodiment of this application provides an angle detection method. This method first obtains the target speckle pattern corresponding to the target incident light within the first measurement range. Then, it determines the first correlation value between the target speckle pattern and the first speckle pattern, and determines the position information corresponding to the target incident light based on the first correlation value. Finally, it determines the second correlation value between the target speckle pattern and the second speckle pattern, and determines the incident angle of the target incident light based on the second correlation value and the position information. Among them, the first speckle pattern and the second speckle pattern respectively calibrate the incident angles of the corresponding optical paths.
[0051] In this way, by adopting the method of local calibration and combining the cross-correlation theory, the incident angle of the target incident light is determined according to the target speckle pattern corresponding to the target incident light within the measurement range and the calibrated speckle image, thereby improving the accuracy of angle detection on the basis of reducing the preparation workload.
[0052] It should be noted that an angle detection method, device, equipment and readable storage medium provided by this application can be applied to the field of angle detection. The above is only an example and does not limit the application field of an angle detection method, device, equipment and readable storage medium provided by this application.
[0053] In order to make the objectives, technical solutions and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of this application.
[0054] Figure 1 It is a schematic diagram of an experimental device provided by an embodiment of this application. Combining Figure 1 As shown, the beam emitted by the laser is expanded by an expansion system (lens 1 and lens 2), and then shoots towards the mirror. The mirror reflects the beam to the structured light field generation system. The structured light field generation system consists of a DMD (digital micromirror device) and a 4-f system with a small hole filter. The 4-f system consists of lens 3 and lens 4, conjugates the light field information to the ground glass, and the aperture is used to filter the clutter in the beam. The ground glass is used to generate speckles, and the microscopic device (20x immersion oil objective and lens 5) is used to magnify the speckles. The CCD camera is used to collect the total light intensity and send it to the computer for processing. The focal lengths of lens 1 to lens 5 are 20mm, 1000mm, 300mm, 100mm and 180mm respectively. The angle detection in the embodiment of this application is to detect the incident angle of the incident light shooting towards the ground glass. The preparation work before the experiment can be to locally calibrate the incident light with a given incident angle and its corresponding speckles based on the range of the angular optical memory effect of the ground glass.
[0055] Figure 2 It is a flowchart of an angle detection method provided by an embodiment of this application. Combining Figure 1 As shown, an angle detection method provided by an embodiment of this application may include:
[0056] S201: Obtain the target speckle pattern corresponding to the target incident light within the first measurement range.
[0057] In practical applications, the first measurement range is related to the calibrated effective memory effect, and any incident angle within the calibrated effective memory effect belongs to the first measurement range. The target incident light refers to the beam to be measured that is incident on the ground glass. The speckle pattern generated after the beam to be measured passes through the ground glass is called the target speckle pattern. In the embodiments of the present application, first, a CCD camera is required to collect the target speckle pattern and send it to a computer for subsequent angle detection processing.
[0058] S202: Determine a first correlation value between the target speckle pattern and the first speckle pattern.
[0059] In practical applications, there is a peak and two corresponding valleys on the correlation coefficient function image corresponding to each segment of the effective memory effect. Therefore, in the embodiments of the present application, a local calibration method is adopted to calibrate each segment of the effective memory effect, that is, only the incident angle of the speckle pattern (the first speckle pattern) corresponding to the peak and the incident angle of the speckle pattern (the second speckle pattern) corresponding to the valley are calibrated before the experiment. Thus, if only one segment of the effective memory effect is locally calibrated before the experiment, the first measurement range will be very small, and the number of the first speckle patterns is only one. By performing a cross-correlation operation on the target speckle pattern and this one first speckle pattern through a computer, an accurate value can be obtained, and this accurate value is the first correlation value.
[0060] S203: Determine position information corresponding to the target incident light based on the first correlation value.
[0061] In practical applications, for the case where only one segment of the effective memory effect is locally calibrated before the experiment, the first correlation value corresponds to two points symmetric about the Y-axis on the correlation coefficient function image, and the position information of these two points on the function image is the possible position information corresponding to the target incident light.
[0062] In addition, since the methods for obtaining the position information corresponding to the target incident light are not the same, the embodiments of the present application can illustrate one possible obtaining method.
[0063] In one case, S203: Determine position information corresponding to the target incident light based on the first correlation value, specifically including:
[0064] Based on the first correlation value, use the correlation coefficient function to determine a first included angle and a second included angle between the target incident light and the first incident light corresponding to the first speckle pattern;
[0065] The correlation coefficient function is:
[0066]
[0067] In the formula is the value of the correlation coefficient, k is the wave vector, and L is the thickness of the scattering medium. is the angle between the incident angle of the reference speckle and the incident angle of the target speckle.
[0068] In practical applications, the embodiment of the present application introduces a correlation coefficient function as an evaluation criterion, and sets that when the value of the correlation function drops to 0.2, the boundary of the memory effect is reached. The first correlation value obtained above is the Y value of the function. Substituting the first correlation value into the function and solving the function can obtain the corresponding That is, the angle between the target incident light corresponding to the target speckle pattern and the first incident light corresponding to the first speckle pattern (reference speckle pattern). Based on the characteristics of the function graph, corresponds to two angles, namely the first angle and the second angle, and the two angles are symmetric with respect to the first incident light.
[0069] S204: Determine the second correlation value between the target speckle pattern and the second speckle pattern; the first speckle pattern and the second speckle pattern respectively calibrate the incident angles of the corresponding optical paths.
[0070] In practical applications, continue to illustrate in combination with the situation where only a section of the effective memory effect is locally calibrated before the above experiment. In this case, there is only one first speckle pattern and two corresponding second speckle patterns. By performing a cross-correlation operation on the target speckle pattern and these two second speckle patterns through a computer, two corresponding values can be obtained. The second speckle pattern corresponding to the larger value has a stronger correlation with the target speckle pattern. Therefore, the embodiment of the present application uses the larger value as the second correlation value between the target speckle pattern and the second speckle pattern. Similarly, the embodiment of the present application uses a local calibration method to calibrate each section of the effective memory effect, that is, the incident angles corresponding to the first speckle pattern and the second speckle pattern are calibrated before the experiment.
[0071] S205: Determine the incident angle of the target incident light based on the second correlation value and the position information.
[0072] In practical applications, the position information corresponding to the target incident light determined based on the first correlation value is uncertain, that is, one first correlation value corresponds to two positions on the function graph. The second correlation value refers to the correlation between the target speckle pattern and the second speckle pattern. Due to the principle that the more correlated, the smaller the difference in the incident angles, the unique target position corresponding to the target speckle pattern can be determined from the two positions on the function graph, and then the incident angle of the target incident light can be determined.
[0073] In addition, since the methods for determining the incident angle are not all the same, the embodiment of the present application can illustrate one possible determination method.
[0074] In one case, S205: determining the incident angle of the target incident light based on the second correlation value and the position information specifically includes:
[0075] Determine the maximum value in the second correlation value;
[0076] According to the maximum value, determine the target angle corresponding to the target incident light from the first angle and the second angle;
[0077] Determine the incident angle of the target incident light based on the target angle.
[0078] In practical applications, a first speckle pattern and two corresponding second speckle patterns are calibrated in a period of effective memory effect. The first correlation value corresponds to two positions on the correlation coefficient function image that are symmetric about the Y-axis. To determine the position uniquely corresponding to the target speckle pattern, the embodiments of the present application need to perform cross-correlation processing on the target speckle pattern and the two second speckle patterns respectively, and obtain two second correlation values. Based on the principle that the closer the correlation, the closer the incident angle, the maximum value of the two second correlation values is used to determine the position uniquely corresponding to the target speckle pattern (that is, on the function image, the position of the point corresponding to the target speckle pattern is between the point corresponding to the second speckle pattern with the maximum value and the point corresponding to the first speckle pattern). According to the correlation coefficient function, based on the position uniquely corresponding to the target speckle pattern on the function image, the target angle corresponding to the target incident light can be selected from the first angle and the second angle. Finally, the incident angle of the target incident light is determined based on the target angle and the angle of the first incident angle. For example, if the first incident angle is 0° and the target angle is 1°, then the incident angle of the target incident light is 1°.
[0079] In addition, since the methods for determining the first measurement range are not all the same, the embodiments of the present application can illustrate one possible determination method.
[0080] In one case, the method further includes:
[0081] Determine the range of the angular optical memory effect based on the type and thickness of the scattering medium;
[0082] Based on the range, splice multiple periods of effective memory effect to obtain the corresponding first measurement range.
[0083] In practical applications, there is an expression for the scattering characteristics in a scattering medium: Δθ = λ / 2πL, where Δθ represents the angle between the incident light and the optical axis direction, and λ represents the wavelength of the incident light. From the above formula, it can be seen that for a scattering medium, when its material and thickness are fixed, the range of its angular optical memory effect is also determined. To expand the measurement range, multiple segments of effective memory can be spliced together. Specifically, by combining the above expression, it can be found that as the thickness L of the scattering medium gradually increases, the value of the correlation function will decrease faster and faster, and the range of the angular optical memory effect will become smaller and smaller. Through our experimental measurement, when the thickness L of the scattering medium is approximately 2200 μm, the effective measurement range of the angular optical memory effect is 0.014 rad, which is a very small measurement range. Then, based on the above experiment, as the incident angle increases and the thickness of the incident wavefront passing through the scattering medium remains unchanged, the measurable range is expanded by splicing multiple segments of effective memory effects such as from -0.021 rad to -0.007 rad, from -0.007 rad to 0.007 rad, from 0.007 rad to 0.021 rad, from 0.021 rad to 0.035 rad, etc. The range covered by all the effective memory effects is the first measurement range for subsequently restricting the incident angle of the target incident light.
[0084] In addition, since the calibration content is not the same, the embodiments of the present application can illustrate a possible calibration method.
[0085] In one case, the method further includes:
[0086] Calibrating each peak and valley in the function image based on the multiple segments of effective memory effects and the correlation coefficient function; there are at least two peaks, the valleys correspond to the peaks, and each peak corresponds to two adjacent valleys;
[0087] The speckle pattern corresponding to the peak is the first scattering speckle pattern; the speckle image corresponding to the valley is the second speckle pattern.
[0088] In practical applications, the embodiment of the present application further provides a method for locally calibrating multiple segments of effective memory effects. Specifically, since each segment of effective memory effect has a peak and two valleys on the function image corresponding to the correlation coefficient function. Therefore, when the first measurement range includes multiple segments of effective memory effects, it is necessary to calibrate one peak and two valleys corresponding to each segment of effective memory effect on the function image of the correlation coefficient function. It can be understood that on the correlation coefficient function image corresponding to multiple segments of effective memory effects, each peak corresponds to two adjacent valleys. At the same time, the speckle pattern corresponding to the peak is used as the first scattering speckle pattern, and the speckle image corresponding to the valley is used as the second speckle pattern. At this time, the number of calibrated first speckle patterns is consistent with the number of segments of effective memory effects, and there are at least two. Each first speckle image has two corresponding second speckle images.
[0089] In addition, since the methods for determining the first correlation value corresponding to different numbers of first speckle patterns are different, the embodiment of the present application can illustrate one possible determination method.
[0090] In one case, S202: Determining the first correlation value between the target speckle pattern and the first speckle pattern specifically further includes:
[0091] Performing cross-correlation processing on the target speckle pattern and each of the first speckle patterns respectively, and obtaining candidate correlation values corresponding to each of the first speckle patterns;
[0092] Comparing the magnitudes of the candidate correlation values, and taking the candidate correlation value with the largest value as the first correlation value.
[0093] In practical applications, continuing with the case of locally calibrating multiple segments of effective memory effects before the experiment, that is, the case where the measurement range is expanded. Since there are multiple calibrated first speckle patterns, the computer needs to select one first speckle pattern from all the calibrated first speckle patterns for angle detection of the target incident light. Specifically, performing cross-correlation processing on the target speckle pattern and each of the first speckle patterns, and obtaining multiple candidate correlation values. It should be noted that on the function image, the position corresponding to the target speckle pattern may fall into any segment of effective memory effect. Among the numerous calibrated peaks, the segment of effective memory effect where the peak closest to the position corresponding to the target speckle pattern is located is the effective memory effect corresponding to the target speckle pattern. Based on the principle that the closer the value is, the larger the correlation value is, the embodiment of the present application performs cross-correlation processing on the target speckle pattern and each of the calibrated first speckle patterns respectively, and obtains candidate correlation values corresponding to each of the first speckle patterns. By comparison, the candidate correlation value with the largest value is taken as the first correlation value.
[0094] In addition, since the methods for determining the second speckle pattern are not the same, embodiments of the present application can illustrate one possible determination method.
[0095] In one case, the method further includes:
[0096] Determining a first speckle pattern corresponding to the target speckle pattern according to the candidate correlation value with the largest value;
[0097] Determining a second speckle pattern corresponding to the target speckle pattern based on the first speckle pattern.
[0098] In practical applications, combining the above, the first speckle pattern corresponding to the candidate correlation value with the largest value is used as the first speckle pattern corresponding to the target speckle pattern. This means that on the function image, the position corresponding to the target speckle image falls within the function image of a section of effective memory effect corresponding to this first speckle image. Since in each section of effective memory effect, one first speckle pattern corresponds to two second speckle patterns, therefore, when the first speckle pattern corresponding to the target speckle image is determined, the two second speckle images corresponding to the target speckle image can be determined. Then, combining the angle detection method provided above, the only second speckle pattern more relevant to the target speckle pattern is determined through cross-correlation processing, and then inversion is performed according to the correlation coefficient function, and the wavefront phase detection beyond the memory effect range can be completed through the scattering medium, that is, the angle detection of the target speckle pattern. The resolution accuracy of this technology is 0.0001 rad.
[0099] Figure 3 This is an experimental effect diagram provided by an embodiment of the present application. Combining Figure 3 As shown, in the embodiment of the present application, the wavefront is changed between -0.133 rad and 0.133 rad by controlling the digital micromirror array, and the phase change is detected by the above method to obtain the detection result. The comparison effect between the detection result and the actual phase change shows that the mean square error is 4.77×10 -5 .
[0100] In summary, the present application first obtains the target speckle pattern corresponding to the target incident light within the first measurement range. Then, the first correlation value between the target speckle pattern and the first speckle pattern is determined, and the position information corresponding to the target incident light is determined based on the first correlation value. Finally, the second correlation value between the target speckle pattern and the second speckle pattern is determined, and the incident angle of the target incident light is determined based on the second correlation value and the position information. Among them, the first speckle pattern and the second speckle pattern respectively calibrate the incident angles of the corresponding optical paths. In this way, by using the method of local calibration and combining the cross-correlation theory, the incident angle of the target incident light is determined according to the target speckle pattern corresponding to the target incident light within the measurement range and the calibrated speckle image, thereby improving the accuracy of angle detection on the basis of reducing the preparation workload.
[0101] Based on the angle detection method provided in the above embodiments, an angle detection device is also provided in an embodiment of the present application. The angle detection device will be described below in combination with the embodiments and the accompanying drawings respectively.
[0102] Figure 4 It is a schematic structural diagram of an angle detection device provided in an embodiment of the present application. Combining Figure 4 As shown, the angle detection device 400 provided in an embodiment of the present application includes:
[0103] An acquisition module 401, configured to acquire a target speckle pattern corresponding to target incident light within a first measurement range;
[0104] A first determination module 402, configured to determine a first correlation value between the target speckle pattern and a first speckle pattern;
[0105] A second determination module 403, configured to determine position information corresponding to the target incident light based on the first correlation value;
[0106] A third determination module 404, configured to determine a second correlation value between the target speckle pattern and a second speckle pattern; the first speckle pattern and the second speckle pattern respectively calibrate corresponding optical path incident angles;
[0107] A fourth determination module 405, configured to determine the incident angle of the target incident light based on the second correlation value and the position information.
[0108] As an implementation manner, for how to determine the position information corresponding to the target incident light, the above-mentioned second determination module 403 is specifically configured to:
[0109] Based on the first correlation value, use a correlation coefficient function to determine a first included angle and a second included angle between the target incident light and a first incident light corresponding to the first speckle pattern;
[0110] The correlation coefficient function is:
[0111]
[0112] In the formula is the value of the correlation coefficient, k is the wave vector, L is the thickness of the scattering medium, is the included angle between the incident angle of the reference speckle and the incident angle of the target speckle.
[0113] As an implementation manner, for how to determine the incident angle of the target incident light, the above-mentioned fourth determination module 405 is specifically configured to:
[0114] Determine the maximum value in the second correlation value;
[0115] Determine a target angle corresponding to the target incident light from the first included angle and the second included angle according to the maximum value;
[0116] Determine the incident angle of the target incident light based on the target angle.
[0117] As an implementation manner, for how to determine the first measurement range, the above-mentioned angle detection device 400 further includes a fifth determination module;
[0118] The fifth determination module is used to determine the range of the angular optical memory effect based on the type and thickness of the scattering medium;
[0119] Based on the range, splice multiple segments of effective memory effects to obtain the corresponding first measurement range.
[0120] As an implementation manner, for how to calibrate the first speckle pattern and the second speckle pattern, the above-mentioned angle detection device 400 further includes: a calibration module;
[0121] The calibration module is used to calibrate each peak and valley in the function image based on the multiple segments of effective memory effects and the correlation coefficient function; there are at least two peaks, the valleys correspond to the peaks, and each peak corresponds to two adjacent valleys;
[0122] The speckle pattern corresponding to the peak is the first scattering speckle pattern; the speckle image corresponding to the valley is the second speckle pattern.
[0123] As an implementation manner, for how to determine the first correlation value, the above-mentioned first determination module 402 is specifically used for:
[0124] Perform cross-correlation processing on the target speckle pattern and each first speckle pattern respectively, and obtain candidate correlation values corresponding to the respective first speckle patterns;
[0125] Compare the magnitudes of the candidate correlation values, and use the candidate correlation value with the largest value as the first correlation value.
[0126] As an implementation manner, for how to determine the second speckle pattern, the above-mentioned angle detection device 400 further includes: a sixth determination module;
[0127] The sixth determination module is used to determine the first speckle pattern corresponding to the target speckle pattern according to the candidate correlation value with the largest value;
[0128] Determine the second speckle pattern corresponding to the target speckle pattern based on the first speckle pattern.
[0129] In summary, the present application first obtains a target speckle pattern corresponding to target incident light within a first measurement range. Then, it determines a first correlation value between the target speckle pattern and a first speckle pattern, and determines position information corresponding to the target incident light based on the first correlation value. Finally, it determines a second correlation value between the target speckle pattern and a second speckle pattern, and determines the incident angle of the target incident light based on the second correlation value and the position information. Among them, the first speckle pattern and the second speckle pattern respectively calibrate the incident angles of the corresponding optical paths. In this way, by adopting a local calibration method and combining the cross-correlation theory, the incident angle of the target incident light is determined according to the target speckle pattern corresponding to the target incident light within the measurement range and the calibrated speckle image, thereby improving the accuracy of angle detection on the basis of reducing the preparation workload.
[0130] In addition, the present application also provides an angle detection device, including: a memory for storing a computer program; a processor for implementing the steps of the angle detection method as described above when executing the computer program.
[0131] In addition, the present application also provides a readable storage medium, on which a computer program is stored, and the computer program implements the steps of the angle detection method as described above when executed by a processor.
[0132] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. An angle detection method, characterized in that: The method comprises: Acquire a target speckle pattern corresponding to the target incident light within a first measurement range; determining a first correlation value between the target speckle pattern and a first speckle pattern; determining position information corresponding to the target incident light based on the first correlation value; Determining a second correlation value between the target speckle pattern and a second speckle pattern; the first speckle pattern and the second speckle pattern respectively calibrate a pair of optical path incident angles; An incident angle of the target incident light is determined based on the second correlation value and the position information.
2. The method according to claim 1, characterized in that The determining, based on the first correlation value, position information corresponding to the target incident light comprises: Based on the first correlation value, determining a first angle and a second angle between the target incident light and the first incident light corresponding to the first speckle pattern using a correlation coefficient function; The correlation coefficient function is: In the formula is the value of the correlation coefficient, k is the wave vector, L is the thickness of the scattering medium, is the angle between the incident angle of the reference speckle and the incident angle of the target speckle.
3. The method according to claim 2, characterized in that The determining the incident angle of the target incident light based on the second correlation value and the position information includes: determining a maximum value among said second correlation values; Determining a target angle corresponding to the target incident light from the first angle and the second angle according to the maximum value; An incident angle of the target incident light is determined based on the target included angle.
4. The method according to claim 1, characterized in that The method further comprises: Determine the extent of the angular optical memory effect based on the type and thickness of the scattering medium; Based on the range, multiple sections of effective memory effects are spliced to obtain a corresponding first measurement range.
5. The method according to claim 4, characterized in that The method further comprises: The peaks and troughs in the function image are calibrated based on the multiple effective memory effects and correlation coefficient functions; the peaks are at least two, the troughs correspond to the peaks, and each peak corresponds to two adjacent troughs; The speckle pattern corresponding to the wave crest is the first speckle pattern; the speckle image corresponding to the wave trough is the second speckle pattern.
6. The method according to claim 5, characterized in that The determining a first correlation value between the target speckle pattern and the first speckle pattern comprises: Performing cross-correlation processing on the target speckle pattern and each first speckle pattern respectively, and obtaining a candidate correlation value corresponding to each first speckle pattern; The sizes of the candidate correlation values are compared, and the candidate correlation value with the largest value is taken as the first correlation value.
7. The method according to claim 1, characterized in that The method further comprises: Determine a first speckle pattern corresponding to the target speckle pattern according to the largest candidate correlation value; A second speckle pattern corresponding to the target speckle pattern is determined based on the first speckle pattern.
8. An angle detection device, characterized in that: include: An acquisition module, used to acquire a target speckle pattern corresponding to the target incident light within a first measurement range; A first determining module, configured to determine a first correlation value between the target speckle pattern and a first speckle pattern; A second determination module, configured to determine position information corresponding to the target incident light based on the first correlation value; a third determining module, configured to determine a second correlation value between the target speckle pattern and a second speckle pattern; The first speckle pattern and the second speckle pattern respectively calibrate corresponding light path incident angles; A fourth determination module is used to determine the incident angle of the target incident light based on the second correlation value and the position information.
9. An angle detection device, characterized in that: include: Memory for storing computer programs; A processor, configured to implement the steps of the angle detection method according to any one of claims 1 to 7 when executing the computer program.
10. A readable storage medium, characterized in that: The readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the angle detection method according to any one of claims 1 to 7 are implemented.