Optical device angle offset measurement method and device for high-speed optical module

Abstract

The application relates to the technical field of optical measurement, in particular to an optical device angle offset measurement method and device for a high-speed optical module. The method collects a light spot image, acquires light spot pixel points, concentric circles and circle sub-regions, calculates the light spot distribution difference degree, offset regularity and circle center possibility of a first circle center, calculates the symmetry regularity, light spot edge fitting degree and real circle center evaluation value of the first circle center, determines the real optical center of the light spot image, and calculates the angle offset of the optical device according to the real optical center. The application can improve the accuracy of optical device angle offset measurement.

Description

Technical Field

[0001] This application relates to the field of optical measurement technology, specifically to a method and apparatus for measuring the angular offset of optical devices for high-speed optical modules. Background Technology

[0002] The optical components of a high-speed optical module are the core optical elements within the module that perform optical-to-electrical or electro-optical signal conversion, responsible for transmitting, receiving, and coupling optical signals. They are the foundation for the signal conversion function of the optical module. Optical component angular offset measurement refers to measuring the deviation between the actual installation angle of the core optical component inside the optical module and the design reference angle using optical detection methods. Optical component angular offset measurement can ensure optical coupling efficiency, improve transmission performance, reduce signal crosstalk, and improve the signal-to-noise ratio.

[0003] The angular offset of optical devices can be measured using the spot scanning method, the key to which lies in the identification and positioning of the spot. However, optical signals are easily affected by external interference during propagation, causing irregular spot images and resulting in a deviation between the acquired optical center and the true optical center, leading to inaccurate angular offset measurement results. Summary of the Invention

[0004] To address the aforementioned technical problems, this application provides a method and apparatus for measuring the angular offset of optical devices in high-speed optical modules. The specific technical solution adopted is as follows:

[0005] In a first aspect, one embodiment of this application provides a method for measuring the angular offset of optical devices in a high-speed optical module, the method comprising the following steps:

[0006] Acquire light spot images and identify the initial optical center in the light spot images;

[0007] Based on the differences in the center position and radius of the circles identified from the spot image, a first center is set, concentric circles and annexes of the first center are established, and the concentric annexes are divided into annular sub-regions; spot pixels in the spot image are identified; the spot distribution difference degree of the first center is calculated based on the difference in the number of spot pixels contained in different annular sub-regions of the first center; the offset regularity of the first center is calculated based on the difference in the number of pixels contained in the annular sub-regions corresponding to different concentric annexes of the first center and the concentric annexes containing the annular sub-regions, and combined with the spot distribution difference degree, the probability of the first center being the center is obtained;

[0008] Based on the difference in gray values ​​of pixels contained in adjacent ring sub-regions corresponding to different concentric rings of the first center, the symmetry regularity of the first center is calculated. Based on the positional distribution of edge pixels in the concentric circles of the first center and the spot pixels, the edge fitting degree of the first center is calculated. Combining the probability of the first center and the symmetry regularity, the true center evaluation value of the first center is calculated. Based on the true center evaluation values ​​of the first center and its adjacent pixels, the true light center of the spot image is determined.

[0009] Calculate the angular offset of the optical device based on the true optical center of the light spot image.

[0010] Furthermore, the specific methods for setting the first center, establishing concentric circles and annexes around the first center, and dividing the annulus into annular sub-regions are as follows:

[0011] Identify all circles in the edge image of the light spot, and determine the coordinates of the first circle's center based on the coordinates of the centers of all identified circles and the initial light center;

[0012] The minimum absolute value of the difference between the radii of all the identified different circles is used as the radius step size; based on the radii of all the identified circles, the shortest standard radius and the longest standard radius are determined; the longest standard radius is reduced by taking the first circle center as the center and the longest standard radius as the radius, with the radius step size as the step size, until the radius is smaller than the shortest standard radius, thus obtaining concentric circles; the annulus formed by adjacent concentric circles is taken as the concentric annulus with the first circle center;

[0013] The concentric rings with the first center are each divided into ring sub-regions.

[0014] Furthermore, the method for obtaining the difference in the light spot distribution at the center of the first circle is as follows:

[0015] The average number of light spot pixels contained in all annular sub-regions of the first circle is denoted as the standard number of light spots at the first circle.

[0016] The normalized sum of the absolute values ​​of the differences between the number of spot pixels contained in all annular sub-regions of the first circle and the number of standard spots is denoted as the spot distribution difference degree of the first circle.

[0017] Furthermore, the method for obtaining the regularity of the offset of the first circle center is as follows:

[0018] The two concentric rings with different centers are denoted as the first concentric ring and the second concentric ring, respectively. Any one of the corresponding ring sub-regions of the first concentric ring and the second concentric ring is denoted as the target ring sub-region.

[0019] The ratio of the number of pixels contained in the target annular sub-region of the first concentric annulus to the number of pixels contained in the first concentric annulus is denoted as the first ratio of the first concentric annulus. The ratio of the number of pixels contained in the target annular sub-region of the second concentric annulus to the number of pixels contained in the second concentric annulus is denoted as the second ratio of the second concentric annulus.

[0020] The absolute value of the difference between the first ratio of the first concentric ring and the second ratio of the second concentric ring is denoted as the first absolute value of the first and second concentric rings in the target ring sub-region. Based on the first absolute values ​​of the first and second concentric rings in all corresponding ring sub-regions, the first cumulative sum of the first and second concentric rings is calculated. The negative correlation processing result of the first cumulative sum of all different concentric rings of the first center is denoted as the offset regularity of the first center.

[0021] Furthermore, the method for obtaining the probability of the center of the first circle is as follows:

[0022] The normalized value of the ratio of the regularity of the first circle's offset to the difference in the distribution of the light spot is denoted as the probability of the first circle's center.

[0023] Furthermore, the method for obtaining the symmetry regularity of the first circle center is as follows:

[0024] The difference between the average gray values ​​of the pixels contained in the first concentric ring and the second concentric ring in the target ring sub-region is denoted as the average gray value difference between the first concentric ring and the second concentric ring in the target ring sub-region. Adjacent ring sub-regions are determined in a clockwise direction. The absolute value of the difference between the average gray value difference between the first concentric ring and the second concentric ring in the target ring sub-region and the adjacent ring sub-region is denoted as the symmetrical gray value difference between the first concentric ring and the second concentric ring in the target ring sub-region.

[0025] The sum of the symmetrical grayscale differences of the first and second concentric rings in all corresponding ring sub-regions is denoted as the third sum of the first and second concentric rings. The negative correlation result of the third sum of all different concentric rings at the first center is denoted as the symmetrical regularity of the first center.

[0026] Furthermore, the method for obtaining the edge fitting degree of the light spot at the center of the first circle is as follows:

[0027] All pixels on the edge of the region formed by the light spot pixels are denoted as light spot edge pixels, and the concentric circle with the largest number of light spot edge pixels and the first center is denoted as the standard concentric circle.

[0028] The minimum distance between the edge pixel of the light spot and all pixels on the standard concentric circle is denoted as the standard difference distance of the edge pixel of the light spot. The negative correlation result of the standard difference distances of all edge pixels of the light spot is denoted as the edge fitting degree of the first circle.

[0029] Furthermore, the true center evaluation value of the first circle is: the positive correlation between the probability of the first circle center, the symmetry regularity, and the fitting degree of the light spot edge.

[0030] Furthermore, the method for determining the true optical center of the light spot image is as follows:

[0031] Calculate the true center evaluation value of all points within the eight-neighborhood of the first center, and take the point with the largest true center evaluation value of all points within the eight-neighborhood of the first center as the center to be determined;

[0032] The point with the highest evaluation value of the true center of the circle to be determined is taken as the updated center of the circle to be determined. This process is repeated until the center of the circle to be determined can no longer be updated. The center of the circle to be determined is then taken as the true optical center of the spot image.

[0033] Secondly, another embodiment of this application provides an optical device angle offset measurement device for high-speed optical modules, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the above-described optical device angle offset measurement method for high-speed optical modules.

[0034] The embodiments of this application have at least the following beneficial effects:

[0035] This application establishes concentric rings with a first center as the center. Based on the characteristic that the gray values ​​of pixels in an ideal light spot image should be uniformly distributed, the distribution difference of the light spot at the first center is obtained. Since angular offset easily leads to uneven distribution of light spot pixels within the concentric rings in the light spot image, the differences in the proportion of pixels contained in the sub-regions of the rings corresponding to different concentric rings at the first center are analyzed to obtain the offset regularity of the first center. The smaller the offset regularity, the more significant the regular distribution characteristics caused by the angular offset, and the higher the probability that the first center is the true light center, thus obtaining the probability of the first center being the center; furthermore, the light spot at the first center... Symmetry analysis is performed to obtain the symmetry regularity of the first circle center. Based on the positions of the concentric circles of the first circle center and the edge pixels in the spot pixels, the similarity between the edge pixels of the spot and the shape of the standard concentric circles is judged to obtain the spot edge fitting degree of the first circle center. Then, the true circle center evaluation value of the first circle center is calculated. Based on the true circle center evaluation values ​​of the first circle center and its adjacent pixels, the true optical center of the spot image is determined. The true optical center is the accurately located spot center. Finally, based on the true optical center of the spot image, the angular offset of the optical device is calculated to solve the problem of inaccurate spot positioning leading to deviations in the angular offset measurement results of the optical device. Attached Figure Description

[0036] To more clearly illustrate the technical solutions and advantages in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 This is a flowchart illustrating the steps of a method for measuring the angular offset of optical devices in a high-speed optical module, as provided in one embodiment of this application. Detailed Implementation

[0038] To further illustrate the technical means and effects adopted by this application to achieve the intended purpose of the invention, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effects of the optical device angle offset measurement method and apparatus for high-speed optical modules proposed in this application. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0040] The following description, in conjunction with the accompanying drawings, details the specific scheme of the optical device angle offset measurement method and device for high-speed optical modules provided in this application.

[0041] Please see Figure 1 The document illustrates a flowchart of a method for measuring the angular offset of optical devices in a high-speed optical module according to an embodiment of this application. The method includes the following steps:

[0042] Step S001: Acquire a light spot image and identify the initial optical center in the light spot image.

[0043] An imaging lens is used to reflect and focus the laser light spot from the optical device onto the screen onto a CCD sensor, which then acquires the image of the light spot. The centroid of the light spot image is obtained using the centroid method, and this centroid is recorded as the initial optical center.

[0044] At this point, the initial optical center in the light spot image is obtained.

[0045] Step S002: Based on the differences in center position and radius between the circle identified from the spot image and the initial optical center, a first center is set, concentric circles and annexes of the first center are established, and the concentric annexes are divided into annular sub-regions; spot pixels in the spot image are identified; the spot distribution difference degree of the first center is calculated based on the difference in the number of spot pixels contained in different annular sub-regions of the first center; the offset regularity of the first center is calculated based on the difference in the number of pixels contained in the annular sub-regions corresponding to different concentric annexes of the first center and the concentric annexes containing the annular sub-regions, and the probability of the center of the first center is obtained by combining the spot distribution difference degree.

[0046] An ideal light spot image should have uniformly distributed gray values ​​among its pixels. Based on this characteristic, the uniformity of pixel distribution and the regularity of gray value distribution within the annular region divided by the Hough circle can be evaluated, and the probability that the optical center corresponds to the true optical center can be analyzed. The worse the uniformity of pixel distribution and the weaker the regularity of gray value distribution within the annular region determined by the optical center, the lower the probability that the optical center is the true optical center; conversely, the closer the optical center is to the true optical center.

[0047] Edge detection is performed on the spot image to obtain the spot edge image. The Hough circle algorithm is used to identify all circles in the spot edge image. The arithmetic mean of the x-coordinates of all identified circles and the initial optical center is used as the x-coordinate value, and the arithmetic mean of the y-coordinates of all identified circles and the initial optical center is used as the y-coordinate value to obtain the coordinates of the first circle center. The minimum absolute value of the difference between the radii of all identified different circles is used as the radius step size. When the radius step size is less than a first preset parameter, the radius step size is set to the first preset parameter. The minimum radius of all identified circles is recorded as the shortest standard radius, and the maximum radius of all identified circles is recorded as the longest standard radius. Using the first circle center as the center and the longest standard radius as the radius, the longest standard radius is reduced by the radius step size until it is less than the shortest standard radius, obtaining concentric circles. The annulus formed by adjacent concentric circles is taken as the concentric annulus of the first circle center. The concentric annulus of the first circle center is divided into equal parts in the same way. A circular sub-region.

[0048] Specifically, the annular sub-region is divided as follows: Centered on the first circle, sectors are divided along the circumference at preset angular intervals. Each concentric circle is divided into several sector-shaped annular regions, which are the annular sub-regions. The preset angular intervals are determined by… The value of is determined.

[0049] In this embodiment, the first preset parameter is set to 1; the number of concentric circles obtained is the same as the number of all circles identified by the Hough circle algorithm. This represents the first preset quantity, which is 8 in this embodiment.

[0050] Pixels in the spot image with gray values ​​greater than a first preset threshold are denoted as spot pixels. The average number of spot pixels contained in all annular sub-regions of the first circle is denoted as the standard spot count of the first circle. The normalized sum of the absolute values ​​of the differences between the number of spot pixels contained in all annular sub-regions of the first circle and the standard spot count is denoted as the spot distribution difference of the first circle.

[0051] In this embodiment, the first preset threshold value is 128. In this embodiment, the sigmoid function is used to calculate the normalized value. The sigmoid function is a well-known technology and will not be described in detail here. As other implementation methods, implementers can use other methods of the prior art, such as the tanh function.

[0052] When the number of light spot pixels contained in all the annular sub-regions of the first center is closer, the difference in the distribution of light spots at the first center is smaller, and at this time, the probability that the first center is the true center of the light spot is greater.

[0053] Angular offset can easily lead to uneven distribution of pixels within concentric rings in a light spot image. In this case, the closer the optical center is to the true location, the more regular the pixel distribution around the optical center becomes, i.e., the pixels are generally biased towards one side of the light spot image. Therefore, we analyzed the differences in the proportion of pixels contained in the sub-regions of the rings corresponding to different concentric rings of the first center. The smaller the difference, the more significant the regular distribution characteristics caused by the angular offset, and the higher the probability that the first center is the true optical center.

[0054] Since the concentric rings at the first center are divided into annular sub-regions in the same way, different concentric rings have corresponding annular sub-regions. Let the two different concentric rings at the first center be designated as the first concentric ring and the second concentric ring, respectively. Let any corresponding annular sub-region of the first and second concentric rings be designated as the target annular sub-region. Let the ratio of the number of pixels in the target annular sub-region of the first concentric ring to the number of pixels in the first concentric ring be designated as the first ratio of the first concentric ring. Let the ratio of the number of pixels in the target annular sub-region of the second concentric ring be designated as the first ratio of the first concentric ring. The ratio of the number of points to the number of pixels contained in the second concentric ring is denoted as the second ratio of the second concentric ring; the absolute value of the difference between the first ratio of the first concentric ring and the second ratio of the second concentric ring is denoted as the first absolute value of the first and second concentric rings in the target ring sub-region; the sum of the first absolute values ​​of the first and second concentric rings in all corresponding ring sub-regions is denoted as the first sum of the first and second concentric rings; and the negative correlation processing result of the first sums of all different concentric rings of the first center is denoted as the offset regularity of the first center.

[0055] It is understandable that a negative correlation is applied to the first cumulative sum of all different concentric rings around the first center, ensuring a negative correlation between the first cumulative sum of all different concentric rings around the first center and the offset regularity of the first center. It is also understood that the negative correlation in this application refers to the relationship between the independent and dependent variables, where the independent variable is the first cumulative sum of all different concentric rings around the first center, and the dependent variable is the offset regularity of the first center. The negative correlation means that the dependent variable decreases (increases) as the independent variable increases (decreases), and can be an inverse relationship, a subtraction relationship, etc.

[0056] Preferably, as an embodiment of this application, the normalized value of the sum of the sums of the first sums of all different concentric rings of the first center is recorded as the second sum of the first center, and the difference between the number 1 and the second sum of the first center is recorded as the offset regularity of the first center.

[0057] In this embodiment, the sigmoid function is used to calculate the normalized value. The sigmoid function is a well-known technology and will not be described in detail here. As other implementation methods, implementers can use other methods of the prior art, such as the tanh function.

[0058] The smaller the regularity of the offset of the first center, the greater the possibility that the overall offset of the light spot at the first center is caused by interference from other factors, and the greater the possibility that the first center is the true center of the light spot.

[0059] The normalized value of the ratio of the regularity of the first circle's offset to the difference in the distribution of the light spot is denoted as the probability of the first circle's center.

[0060] In this embodiment, the sigmoid function is used to calculate the normalized value. The sigmoid function is a well-known technique and will not be described in detail here. In other implementations, the implementer can use other methods from the prior art, such as the tanh function. During the ratio calculation, to avoid the denominator being zero, a preset value needs to be added to the denominator. In this embodiment, the preset value is 0.01.

[0061] The greater the probability that the first center is the center of the circle, the greater the probability that the first center is the true center of the light spot.

[0062] At this point, we have determined the possible centers of the first circle.

[0063] Step S003: Based on the difference in grayscale values ​​of pixels contained in adjacent ring sub-regions corresponding to different concentric rings of the first center, calculate the symmetry regularity of the first center. Based on the positional distribution of edge pixels in the concentric circles of the first center and the spot pixels, calculate the edge fitting degree of the first center. Combining the probability of the first center and the symmetry regularity, calculate the true center evaluation value of the first center. Based on the true center evaluation values ​​of the first center and its adjacent pixels, determine the true optical center of the spot image.

[0064] Based on the differences in pixel grayscale values ​​in the sub-regions of the concentric rings corresponding to the first center, we analyze whether the light spot at the first center exhibits symmetry. The more significant the central symmetry of the light spot at the first center, the greater the likelihood that the first center is the true center of the light spot.

[0065] The difference between the mean gray values ​​of the pixels contained in the target annular sub-region by the first and second concentric rings is denoted as the average gray-level difference between the first and second concentric rings in the target annular sub-region. Following a clockwise direction, the next adjacent annular sub-region of the target annular sub-region of the first and second concentric rings is denoted as the adjacent annular sub-region. The absolute value of the difference between the average gray-level differences of the first and second concentric rings in the target annular sub-region and the adjacent annular sub-region is denoted as the symmetrical gray-level difference between the first and second concentric rings in the target annular sub-region. The sum of the symmetrical gray-level differences of the first and second concentric rings in all corresponding annular sub-regions is denoted as the third sum of the first and second concentric rings. The negative correlation result of the third sum of all different concentric rings at the first center is denoted as the symmetrical regularity of the first center.

[0066] Preferably, as an embodiment of this application, the difference between the value 1 and the normalized value of the third cumulative sum of all different concentric rings of the first center is denoted as the symmetry regularity of the first center.

[0067] In this embodiment, the sigmoid function is used to calculate the normalized value.

[0068] The greater the symmetry of the first center, the smaller the difference in grayscale values ​​of pixels in the sub-regions corresponding to the different concentric rings of the first center, the more significant the central symmetry of the light spot at the first center, and the greater the possibility that the first center is the true center of the light spot.

[0069] All pixels on the edge of the region formed by the light spot pixels are denoted as light spot edge pixels. The concentric circle with the largest number of light spot edge pixels and the first center is denoted as the standard concentric circle. The minimum distance between the light spot edge pixels and all pixels on the standard concentric circle is denoted as the standard difference distance of the light spot edge pixels. The negative correlation result of the standard difference distances of all light spot edge pixels is denoted as the light spot edge fitting degree of the first center.

[0070] Preferably, as an embodiment of this application, the ratio of the mean of the standard difference distances of all edge pixels of the light spot to the maximum value of the standard difference distances of all edge pixels of the light spot is denoted as the standard distance ratio of the first center, and the difference between the number 1 and the standard distance ratio of the first center is denoted as the light spot edge fitting degree of the first center.

[0071] When the standard difference distance of the edge pixels of the light spot is smaller and there are more edge pixels of the light spot on the standard concentric circle, the shape of the edge pixels of the light spot is closer to that of the standard concentric circle, and the first center is more likely to be the true light center.

[0072] The positive correlation between the probability of the first center, the symmetry regularity, and the fitting degree of the light spot edge is recorded as the true center evaluation value of the first center.

[0073] Preferably, as an embodiment of this application, the product of the probability of the first center, the symmetry regularity, and the fitting degree of the light spot edge is recorded as the true center evaluation value of the first center.

[0074] Using the same method, calculate the true center evaluation value of all points within the eight-neighborhood of the first center. Take the point with the largest true center evaluation value among all points within the eight-neighborhood of the first center as the center to be determined. Take the point with the largest true center evaluation value among all points within the eight-neighborhood of the center to be determined as the updated center to be determined. Repeat the update process until the center to be determined can no longer be updated. Take the center to be determined as the true optical center of the spot image.

[0075] The conditions under which updates cannot continue include: the current true center evaluation value of the circle to be determined is not greater than the true center evaluation value of the circle to be determined in the previous round, or the number of iterations reaches a preset maximum iteration threshold, to prevent the algorithm from falling into an infinite loop. In this embodiment, the maximum iteration threshold is set to 20.

[0076] At this point, the true optical center of the light spot image is obtained.

[0077] Step S004: Calculate the angular offset of the optical device based on the true optical center of the light spot image.

[0078] Calculate the angular offset of the optical device based on the true optical center of the light spot image.

[0079] The calculation of the angular offset of the optical device is a well-known technique and will not be elaborated further. The specific calculation process for the angular offset of the optical device is as follows:

[0080]

[0081] in, Indicates optical devices in Angular offset of direction The direction includes the horizontal axis and the vertical axis, and the unit of angular offset is radians; For the true optical center and the ideal optical center of the light spot image at The offset in direction, the ideal optical center is obtained by a person skilled in the art through calibration; This indicates the pixel size of the light spot image, expressed in mm / pixel. This indicates the effective focal length of the imaging lens, expressed in mm.

[0082] Thus, the measurement results of the optical device angular offset of the high-speed optical module are obtained.

[0083] This application also proposes an optical device angle offset measurement device for high-speed optical modules, including a memory, a processor, and a computer program stored in the memory and executable on the processor. The processor executes the computer program to implement the steps described above. Since the optical device angle offset measurement method for high-speed optical modules has been described in detail above, it will not be repeated here.

[0084] It should be noted that the order of the embodiments described above is merely for descriptive purposes and does not represent the superiority or inferiority of the embodiments. Furthermore, specific embodiments of this specification have been described above. Additionally, the processes depicted in the accompanying drawings do not necessarily require a specific or sequential order to achieve the desired results. In some implementations, multitasking and parallel processing are possible or may be advantageous.

[0085] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0086] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them; modifications to the technical solutions described in the foregoing embodiments, or equivalent substitutions of some of the technical features, do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A method for measuring the angular offset of optical devices in high-speed optical modules, characterized in that, The method includes the following steps: Acquire light spot images and identify the initial optical center in the light spot images; Based on the differences in center position and radius between the circle identified from the spot image and the initial optical center, a first center is set, concentric circles and annexes of the first center are established, and the concentric annexes are divided into annular sub-regions; spot pixels in the spot image are identified; the spot distribution difference degree of the first center is calculated based on the difference in the number of spot pixels contained in different annular sub-regions of the first center; the offset regularity of the first center is calculated based on the difference in the number of pixels contained in the annular sub-regions corresponding to different concentric annexes of the first center and the concentric annexes containing the annular sub-regions, and combined with the spot distribution difference degree, the probability of the first center being the center is obtained; Based on the difference in gray values ​​of pixels contained in adjacent ring sub-regions corresponding to different concentric rings of the first center, the symmetry regularity of the first center is calculated. Based on the positional distribution of edge pixels in the concentric circles of the first center and the spot pixels, the edge fitting degree of the first center is calculated. Combining the probability of the first center and the symmetry regularity, the true center evaluation value of the first center is calculated. Based on the true center evaluation values ​​of the first center and its adjacent pixels, the true light center of the spot image is determined. Calculate the angular offset of the optical device based on the true optical center of the light spot image.

2. The method for measuring the angular offset of optical devices for high-speed optical modules according to claim 1, characterized in that, The specific methods for setting the first center, establishing concentric circles and annexes around the first center, and dividing the annulus into annular sub-regions are as follows: Identify all circles in the edge image of the light spot, and determine the coordinates of the first circle's center based on the coordinates of the centers of all identified circles and the initial light center; The minimum absolute value of the difference between the radii of all the identified different circles is used as the radius step size; based on the radii of all the identified circles, the shortest standard radius and the longest standard radius are determined. Using the first center as the center, the longest standard radius as the radius, and the radius step size as the step size, the longest standard radius is reduced until the radius is smaller than the shortest standard radius to obtain concentric circles; the annulus formed by adjacent concentric circles is taken as the concentric annulus with the first center. The concentric rings with the first center are each divided into ring sub-regions.

3. The method for measuring the angular offset of optical devices for high-speed optical modules according to claim 1, characterized in that, The method for obtaining the difference in the distribution of light spots at the center of the first circle is as follows: The average number of light spot pixels contained in all annular sub-regions of the first circle is denoted as the standard number of light spots at the first circle. The normalized sum of the absolute values ​​of the differences between the number of spot pixels contained in all annular sub-regions of the first circle and the number of standard spots is denoted as the spot distribution difference degree of the first circle.

4. The method for measuring the angular offset of optical devices for high-speed optical modules according to claim 1, characterized in that, The method for obtaining the regularity of the offset of the first circle center is as follows: The two concentric rings with different centers are denoted as the first concentric ring and the second concentric ring, respectively. Any one of the corresponding ring sub-regions of the first concentric ring and the second concentric ring is denoted as the target ring sub-region. The ratio of the number of pixels contained in the target annular sub-region of the first concentric annulus to the number of pixels contained in the first concentric annulus is denoted as the first ratio of the first concentric annulus. The ratio of the number of pixels contained in the target annular sub-region of the second concentric annulus to the number of pixels contained in the second concentric annulus is denoted as the second ratio of the second concentric annulus. The absolute value of the difference between the first ratio of the first concentric ring and the second ratio of the second concentric ring is denoted as the first absolute value of the first and second concentric rings in the target ring sub-region. Based on the first absolute values ​​of the first and second concentric rings in all corresponding ring sub-regions, the first cumulative sum of the first and second concentric rings is calculated. The negative correlation processing result of the first cumulative sum of all different concentric rings of the first center is denoted as the offset regularity of the first center.

5. The method for measuring the angular offset of optical devices for high-speed optical modules according to claim 1, characterized in that, The method for obtaining the probability of the center of the first circle is as follows: The normalized value of the ratio of the regularity of the first circle's offset to the difference in the distribution of the light spot is denoted as the probability of the first circle's center.

6. The method for measuring the angular offset of optical devices for high-speed optical modules according to claim 4, characterized in that, The method for obtaining the symmetry regularity of the first circle center is as follows: The difference between the average gray values ​​of the pixels contained in the first concentric ring and the second concentric ring in the target ring sub-region is denoted as the average gray value difference between the first concentric ring and the second concentric ring in the target ring sub-region. Adjacent ring sub-regions are determined in a clockwise direction. The absolute value of the difference between the average gray value difference between the first concentric ring and the second concentric ring in the target ring sub-region and the adjacent ring sub-region is denoted as the symmetrical gray value difference between the first concentric ring and the second concentric ring in the target ring sub-region. The sum of the symmetrical grayscale differences of the first and second concentric rings in all corresponding ring sub-regions is denoted as the third sum of the first and second concentric rings. The negative correlation result of the third sum of all different concentric rings at the first center is denoted as the symmetrical regularity of the first center.

7. The method for measuring the angular offset of optical devices for high-speed optical modules according to claim 1, characterized in that, The method for obtaining the edge fitting degree of the light spot at the center of the first circle is as follows: All pixels on the edge of the region formed by the light spot pixels are denoted as light spot edge pixels, and the concentric circle with the largest number of light spot edge pixels and the first center is denoted as the standard concentric circle. The minimum distance between the edge pixel of the light spot and all pixels on the standard concentric circle is denoted as the standard difference distance of the edge pixel of the light spot. The negative correlation result of the standard difference distances of all edge pixels of the light spot is denoted as the edge fitting degree of the first circle.

8. The method for measuring the angular offset of optical devices for high-speed optical modules according to claim 1, characterized in that, The true center evaluation value of the first circle is the positive correlation between the probability of the first circle center, the symmetry regularity, and the fitting degree of the light spot edge.

9. The method for measuring the angular offset of optical devices for high-speed optical modules according to claim 1, characterized in that, The method for determining the true optical center of the light spot image is as follows: Calculate the true center evaluation value of all points within the eight-neighborhood of the first center, and take the point with the largest true center evaluation value of all points within the eight-neighborhood of the first center as the center to be determined; The point with the highest evaluation value of the true center of the circle to be determined is taken as the updated center of the circle to be determined. This process is repeated until the center of the circle to be determined can no longer be updated. The center of the circle to be determined is then taken as the true optical center of the spot image.

10. An optical device angle offset measuring device for high-speed optical modules, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the optical device angle offset measurement method for high-speed optical modules as described in any one of claims 1 to 9.

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