Sensor image acquisition device and image acquisition equipment

Abstract

The invention discloses a sensor image acquisition device and image acquisition equipment, and the device comprises at least two linear array sensors which are used for dispersedly acquiring at least two regions in the long-axis direction of a laser image according to preset defocusing amount sampling points; the at least two one-dimensional optical fiber arrays are used for transmitting the image information of each defocusing amount sampling point in the long axis direction of the laser image to the linear array sensor; and the fixer is used for respectively and independently fixing the input ends of the one-dimensional optical fiber arrays according to a preset interval so as to correspond to the defocusing amount sampling points, and enabling the output ends of the one-dimensional optical fiber arrays to be aligned and coupled with the corresponding linear array sensors. According to the invention, through the plurality of independently arranged one-dimensional optical fiber arrays and aligned and coupled with the corresponding single-line linear array image sensors, adaptive adjustment can be carried out according to the length of a laser image, so that sampling is carried out, the problem of insufficient sampling area of a traditional multi-line linear array image sensor is solved, and the sampling precision is improved. And meanwhile, the characteristic advantages of the multi-line linear array sensor are effectively combined, and the defocusing amount sampling rate is improved.

Description

Technical Field

[0001] The present invention belongs to the field of machine vision, and in particular relates to a sensor image acquisition device and image acquisition equipment. Background Art

[0002] Currently, the mainstream microscope autofocus methods can be divided into passive and active.

[0003] Passive methods often use the clarity of the microscopic image captured by the inspection camera to directly calculate the object plane's defocus. This is then fed back to the Z axis, causing the objective lens to move up and down for focusing. The defocus sampling rate of this method is limited by the inspection camera's image frame rate, typically only reaching hundreds of Hz.

[0004] Active methods, on the other hand, typically insert an additional sensor capable of detecting defocus into the microscope's optical path. For example, a coaxial laser light source is used to project the laser directly onto the sample surface. The image sensor that receives the signal analyzes the state of the laser reflected from the sample surface to determine the magnitude and direction of the objective lens's defocus. This allows for real-time detection of the objective lens's defocus, and transmits the defocus signal to the Z-axis actuator for defocus compensation, ensuring that the target object is always within the objective lens' depth of field and that the microscopic image remains clear. Therefore, active laser autofocus methods offer the advantages of a high signal-to-noise ratio, low susceptibility to ambient light interference, a large focus range, and fast focusing speeds.

[0005] Current mainstream active laser autofocus methods typically use multiple image segments or multiple sampling points to sample the defocus signal to enhance focus stability. This requires the use of an area array image sensor for high-speed analysis of multi-point / segment laser image signals. Traditional area array image sensors read row data one by one, and only analyze sampling points along each column after all rows have been read, thereby enabling defocus analysis of multiple sampling points in the laser image. Therefore, the defocus signal sampling rate is limited by the frame rate of the area array image sensor, with a maximum sampling rate typically in the kHz range. At far focus points, the sampling rate further decreases to the hundreds of Hz range as the laser image signal is broadened. Advances in motion control technology have led to the development of Z-axis actuators with response bandwidths in the kHz range, such as piezoelectric ceramic Z-axis actuators. These high-kHz response bandwidths can be used to address the need for tracking focus on target surfaces with high-frequency fluctuations. Consequently, the focus sensor's defocus sampling rate must exceed 10kHz to achieve stable focus feedback.

[0006] Therefore, in order to solve the problem of low sampling rate caused by the defocus sampling rate being limited by the frame rate of the area array image sensor, the present invention proposes a sampling method using a multi-line array image sensor. However, there may also be a problem of insufficient sampling area. In this regard, a sensor imaging device and imaging equipment are provided. Summary of the Invention

[0007] The purpose of the present invention is to overcome the above problems existing in the prior art and provide a sensor imaging device and imaging equipment.

[0008] In order to achieve the above technical objectives and the above technical effects, the present invention is implemented through the following technical solutions: A sensor image acquisition device is used to acquire a semi-elliptical laser image projected on the surface of an object to be measured in an autofocus system to calculate the defocus amount corresponding to the laser image. The device includes: At least two linear array sensors, used for sampling points according to a preset defocus amount and dispersively collecting data from at least two areas in the long axis direction of the laser image; At least two one-dimensional optical fiber arrays are arranged along the long axis of the laser image and perpendicular to the long axis of the laser image, and are used to transmit image information of each defocus sampling point along the long axis of the laser image to the linear array sensor. The area where the linear array sensor collects the laser image is expanded by adjusting the spacing between the one-dimensional optical fiber arrays. A holder is used to independently fix the input ends of the one-dimensional optical fiber array at preset intervals to correspond to the defocus sampling points, and to align and couple the output ends of the one-dimensional optical fiber array with the corresponding linear array sensor; The linear array sensor is a single-row pixel linear array image sensor, and the defocus amount corresponding to the laser image is calculated by analyzing the defocus amounts of valid sampling points among all defocus amount sampling points.

[0009] Furthermore, each one-dimensional optical fiber array is distributed at equal intervals along the long axis direction of the laser image to uniformly collect image information of the laser image.

[0010] Furthermore, the output end of each one-dimensional optical fiber array is aligned with its corresponding linear array sensor and coupled through packaging and bonding.

[0011] Furthermore, the defocus values ​​of valid sampling points among all defocus value sampling points are analyzed, including: Collecting sampling data of the corresponding areas of each one-dimensional optical fiber array in groups to correspond to a number of defocus sampling points respectively; Filtering valid data from all sampled data to obtain a number of valid sampling points, and calculating the defocus amount corresponding to each valid sampling point; The standard deviation of the defocus values ​​at the valid sampling points is analyzed, and several valid defocus values ​​are screened to output the final defocus value.

[0012] Furthermore, after collecting the sampling data of different areas of the laser image along the long axis in groups, when reading the sampling data corresponding to the current area, it is simultaneously analyzed whether the sampling data corresponding to the previous area is valid data.

[0013] Furthermore, the valid data analysis method includes: calculating the maximum grayscale value in each group of sampled data to analyze whether the maximum grayscale value is greater than a grayscale threshold; if so, it is determined to be valid data, otherwise it is invalid data.

[0014] Furthermore, the defocus amount corresponding to each valid sampling point is obtained by calculating the offset between the grayscale centroid of each valid sampling point and the focus reference zero point.

[0015] Furthermore, the effective defocus amount is the defocus amount of the effective sampling points that are within the range corresponding to the standard deviation.

[0016] Furthermore, the final defocus amount is the average of all valid defocus amounts.

[0017] The present invention also provides a map collecting device, comprising: Such as the above-mentioned map collection device; The lens is arranged in front of the one-dimensional optical fiber array along the light propagation path.

[0018] The beneficial effects of the present invention are: (1) The present invention uses several independently arranged one-dimensional optical fiber arrays and aligns and couples them with corresponding single-line array image sensors, which can be adaptively adjusted according to the length of the laser image to perform sampling. This not only solves the problem of insufficient sampling area of ​​traditional multi-line array image sensors, but also effectively combines the characteristic advantages of multi-line array sensors and improves the defocus sampling rate.

[0019] (2) The present invention makes the long axis direction of the light-sensitive line perpendicular to the laser image, so that the image data collected by the light-sensitive line will directly correspond to the sampling data. Therefore, the corresponding sampling point can be calculated after the corresponding data of the current light-sensitive line is read, and the corresponding data of the next light-sensitive line can be read synchronously. This eliminates the resource consumption of the dynamic ROI and eliminates the need to calculate each sampling point after all the corresponding data of all light-sensitive lines are read. It can realize calculation while reading, ensuring that the defocus sampling rate in the near focus and far focus states remains consistent, thereby improving the stability of the working rate of the focusing system. In actual work, only a small amount of The defocus amount can be calculated using the sensitive light line, such as K=10, and the total number of pixel rows in the ROI area is usually higher than 20. It can be seen that compared with the original ROI method, the laser image provided by the present invention has a lower data volume, and the rates of transmission to the processing chip and calculation of the defocus amount are faster, thereby further improving the sampling rate; by flexibly collecting sampling data of different areas of the laser image along the long axis direction in groups, a one-to-one correspondence between the defocus amount sampling points and the sensitive light lines is achieved; by analyzing the valid data in all the sampling data and the standard deviation of the defocus amount of the valid sampling points, the sampling data involved in the defocus amount calculation can be dynamically adjusted to reduce the amount of calculation.

[0020] (3) The present invention can select a multi-line array sensor to significantly reduce the amount of data compared to an area array sensor, thereby increasing the defocus sampling rate to above 10kHz, solving the problem that a conventional single-line array sensor can only achieve high-speed acquisition of a single-point defocus signal but lacks focus stability; it can also be implemented using multiple regions of interest of an area array sensor. By selecting multiple rows of pixel signals of the area array sensor for output, the amount of data can be reduced, and high-speed, multi-point defocus sampling can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings: Figure 1 is a flow chart of the analysis method of the present invention; Figure 2 Schematic diagram of the optical path of the autofocus system in the present invention; Figure 3 Schematic diagram of light beam cross sections corresponding to different object distances in the autofocus system of the present invention; Figure 4 Schematic diagram of a laser image of a conventional area array image sensor in an autofocus system; Figure 5 is a schematic diagram of a laser image of a multi-line array image sensor in an autofocus system; Figure 6 FIG. 1 is a schematic diagram of a laser image in an autofocus system after an area array image sensor is set using multiple regions of interest; Figure 7 It is a structural schematic diagram of the image acquisition device in the present invention; Figure 8 It is a structural block diagram of the analysis system in the present invention.

[0022] In the figure: 1-laser; 2-cylindrical lens; 3-baffle; 4-first beam splitter; 5-second beam splitter; 6-microscope objective; 7-motor; 8-focusing lens; 9-image sensor; 10-object to be measured. DETAILED DESCRIPTION

[0023] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention. Example 1

[0024] This embodiment first provides a high-speed image signal analysis method, which analyzes the collected data of the laser image in the auto-focus system to output the defocus value, wherein the focus optical path of the auto-focus system is as follows: Figure 2 As shown, the details are as follows: The autofocus system includes: a laser 1, a cylindrical lens 2, a baffle 3, a first beam splitter 4, a second beam splitter 5, a microscope objective 6, a motor 7, a focusing lens 8, an image sensor 9, and an object to be measured 10. The circular parallel light emitted by the laser 1 enters the cylindrical lens 2. After being modulated by the cylindrical lens 2, it becomes an asymmetric beam that is collimated in a direction parallel to the paper surface and diverges in a direction perpendicular to the paper surface. After passing through the baffle 3, the asymmetric beam loses half of its energy and propagates only on one side of the optical axis. After being reflected by the first beam splitter 4, it reaches the second beam splitter 5. After being reflected by the second beam splitter 5, it enters one side of the microscope objective 6 and is projected onto the surface of the object to be measured 10 by the microscope objective 6. Due to the reflection of the surface of the object to be measured, the laser light is again collected by the other side of the microscope objective 6. After being reflected by the second beam splitter 5 and refracted by the first beam splitter 4, it reaches the focusing lens 8. After being converged by the focusing lens 8, it is received by the image sensor 9. The defocus amount of the microscope objective lens 6 is calculated according to the state of the light spot received by the image sensor 9, and the defocus amount is converted into a control signal of the motor 7. The motor 7 is driven to drive the microscope objective lens 6 to move, thereby achieving automatic focusing.

[0025] Assume that the focal length of the microscope objective lens 6 is f and the object distance is L. When L increases from less than f to greater than f, the cross-sectional shape of the light beam passing through the microscope objective lens 6 changes, as shown in FIG. Figure 3 As shown, when L is less than f, the cross section of the light beam is an upper semi-ellipse, and the larger L is, the smaller the minor axis length of the ellipse is. When L is equal to f, in the direction parallel to the paper surface, the light beam incident on the microscope objective lens 6 is parallel light, which is converged to a point after being modulated by the microscope objective lens 6. In the direction perpendicular to the paper surface, the light beam incident on the microscope objective lens 6 is divergent light, and is a line segment at the focal position of the microscope objective lens 6. Therefore, the cross section of the light beam is a line with a line width of l. When L is greater than f, the cross section of the light beam is a lower semi-ellipse, and the larger L is, the larger the minor axis length of the ellipse is.

[0026] like Figure 4 The figure shows a schematic diagram of a laser image of a conventional area array image sensor in an autofocus system. Figure 2Image sensor 9 in the image processing apparatus uses an area array image sensor to process the laser image signal reflected from the sample surface. The area array image sensor has N rows of pixels (r1, r2, ..., rN), with the rows of the area array image sensor parallel to the long axis of the laser image. Traditionally, defocus calculations for laser images require cumulatively collecting the grayscale values ​​of all pixels within the entire laser image area and calculating the corresponding defocus values. To reduce the computational complexity and increase the sampling rate, the laser image can be divided into several sub-images by column. The laser line signals in each sub-image can be independently processed to calculate defocus data for K sampling points (s1, s2, ..., sK).

[0027] Depend on Figure 3 It can be seen that near the focus of the objective lens, that is, the focus reference zero point, the width of the laser image in the short axis direction is small and the laser line is thin; away from the focus reference zero point, the laser image will be widened and the laser line will be thick. Therefore, near the focus reference zero point, only a smaller number of lines of image area size is required to fully capture the laser image signal; away from the focus reference zero point, a larger number of lines of image area size is required to capture the complete laser image signal. High-speed area array image sensors need to use global shutter technology. Global shutter area array image sensors have the characteristics that the fewer the number of output lines, the higher the image frame rate. Therefore, Figure 3 The corresponding laser image signal processing method uses dynamic ROI (region of interest) technology to reduce the number of output image lines near the focus reference zero point, which can achieve the highest image frame rate, that is, the defocus sampling rate. However, at farther defocus, the number of image lines increases, the image frame rate decreases, the defocus sampling rate decreases, and the focusing speed decreases.

[0028] Therefore, it can be seen that even if the dynamic ROI technology is used to output only the region of interest corresponding to the laser image, it is still necessary to first read several rows of data corresponding to the dynamic ROI in sequence, and then perform sampling point analysis in each column direction after all rows of data are read, thereby realizing the defocus analysis of multiple sampling points of the laser image.

[0029] In order to further improve the processing speed of laser image signals, such as Figure 1 As shown, the analysis methods include: Step 1: Adjust the sensor posture until the sensor's several light-sensitive lines are perpendicular to the long axis direction of the laser image, so that the image data collected by the light-sensitive lines can be directly used as sampling data, wherein the collection range of the sensor's several light-sensitive lines covers the entire laser image.

[0030] The multiple sensitive lines of the sensor are perpendicular to the long axis of the line laser, so that the multiple sensitive lines can directly divide the line laser image signal. Taking a single line of sensitive lines corresponding to a defocus sampling point as an example, the line data formed by each sensitive line will be sent to the processing chip for reading and processing. At this time, the processing chip can calculate the corresponding sampling point after reading the current line of data, and can also read the next line of data synchronously. When all the line data are read, the calculation of all the sampling points can be completed. Figure 4 In comparison, it not only eliminates the resource consumption of dynamic ROI, but also eliminates the need to wait until all row data are read before calculating the sampling points in all column directions. By combining the row data reading of the sensor with the sampling point calculation, the collected data of each sensitive line can be directly used as the sampling data, which effectively improves the sampling efficiency.

[0031] Step 2: Collect sampling data of different areas of the laser image along the long axis in groups to correspond to several defocus sampling points respectively.

[0032] As a specific embodiment of the present invention, each group of sampling data corresponds to a single line of sensitive light or multiple lines of continuous sensitive light. A single line of sensitive light can correspond to one defocus amount sampling point, or multiple lines of continuous sensitive light can correspond to one defocus amount sampling point.

[0033] like Figure 5 As shown, each pixel column (or light-sensing line) captures a portion of the linear laser segment's sub-image, corresponding to a single defocus sampling point. K defocus sampling points require the linear array image sensor to have K light-sensing lines. Multi-line linear array sensors can achieve defocus sampling rates on the order of 10kHz or even 100kHz, maintaining maximum line frequency in both near and far focus states without requiring dynamic ROI manipulation. Combined with a high-response-bandwidth Z-axis actuator, they achieve ultra-fast focus tracking response, improving adaptability to surfaces with large height variations.

[0034] As a specific embodiment of the present invention, after collecting sampling data of different areas of the laser image along the long axis in groups, when reading the sampling data corresponding to the current area, it is synchronously analyzed whether the sampling data corresponding to the previous area is valid data.

[0035] The corresponding sampling points can be calculated after the corresponding data of the current sensitive line is read, and the corresponding data of the next sensitive line can be read synchronously. This not only eliminates the resource consumption of the dynamic ROI, but also eliminates the need to wait until the corresponding data of all sensitive lines are read before calculating each sampling point. It can realize reading and calculation at the same time, ensuring that the defocus sampling rate in the near focus and far focus states remains consistent, thereby improving the stability of the focusing system's working rate.

[0036] While eliminating the dynamic ROI, this invention still retains the advantage of reduced computational complexity. By cleverly establishing a one-to-one correspondence between defocus sampling points and light-sensitive lines, it further addresses the large data volume inherent in dynamic ROIs when in far focus, maintaining a stable defocus sampling rate in both near and far focus states. Furthermore, since the corresponding sampling points can be calculated after each reading of the corresponding data from the current light-sensitive line, only a small amount of cache space is required to cache image data, significantly reducing resource consumption even compared to dynamic ROIs.

[0037] Since the sampling rate is more than 10 times higher than that of conventional area array image sensor detection solutions, the computing resources required for high-speed image processing per unit time will also increase synchronously. In order to fully utilize the high line frequency of the linear array sensor, when calculating the defocus amount using multiple sampling points, the effective pixel columns can be screened based on the morphological information of the laser profile image received by the image sensor, and the number of pixel columns involved in the defocus amount calculation can be dynamically adjusted to reduce the amount of calculation. The steps for pixel column screening and defocus amount calculation are as follows: Step 3: Filter valid data from all sampled data to obtain a number of valid sampling points, and calculate the defocus amount corresponding to each valid sampling point.

[0038] As a specific implementation of valid data analysis, screening valid data from all sampled data includes: calculating the maximum grayscale value in each group of sampled data to analyze whether the maximum grayscale value is greater than the grayscale threshold. If so, it is determined to be valid data, otherwise it is invalid data, as follows: like Figure 5 As shown, the current image frame is first analyzed to calculate the maximum grayscale value Gmax_i of each of the K pixel columns (c1, c2, ..., cK), where i = 1, 2, ..., K. If Gmax_i is greater than the grayscale threshold G_valid of the valid laser image signal, the data of the corresponding pixel column is considered valid; otherwise, it is invalid, resulting in M ​​valid pixel columns c_i.

[0039] In order to calculate the defocus amount corresponding to each valid sampling point, the offset between the grayscale centroid of each valid sampling point and the focus reference zero point can be calculated as follows: Continue to process M valid pixel columns c_i and calculate the grayscale centroid P_i of each valid pixel column

[0040] Get the defocus value of M effective sampling points

[0041] Where, j=1,2,...,n; G i(j) is the grayscale value of different positions of the effective sampling point, i=1,2,...,M; P_ref is the pixel coordinate of the focus reference zero point, and A_pf is the conversion factor between pixel coordinate and defocus amount.

[0042] Step 4: Analyze the standard deviation of the defocus values ​​at the valid sampling points, and screen out several valid defocus values ​​to output the final defocus value.

[0043] In order to screen and obtain a number of effective defocus values, as a specific embodiment of the present invention, the effective defocus value is the defocus value of the effective sampling points within the range corresponding to the standard deviation, specifically as follows: According to the standard deviation σ of the defocus value F_i of the effective sampling point F , we can further screen out L more reasonable effective defocus values ​​Fv_x, satisfying

[0044] Where x=1,2,...,L.

[0045] After L valid defocus amounts Fv_x are screened and obtained, as a specific embodiment of the present invention, the final defocus amount is the mean of all valid defocus amounts, that is, the mean Fv_mean of Fv_x is calculated as the final single-sample defocus amount output.

[0046] As a specific embodiment of the present invention, the sensor can be a multi-line array image sensor, and the height of the multi-line array image sensor corresponds to the long axis span of the laser image; it can also be an area array image sensor, and includes several regions of interest corresponding to each group of sampling data, and each region of interest corresponds to a single line of sensitive light or multiple lines of continuous sensitive light.

[0047] When using an area array image sensor, a global shutter area array image sensor can be used for simulation, and multiple regions of interest of the global shutter area array image sensor need to be enabled. Figure 6 As shown, the area array image sensor is rotated 90 degrees. The long side of each of the K regions of interest (a1, a2, ..., aK) is perpendicular to the long axis of the line laser focus image signal. Each region of interest can process a single row or multiple consecutive rows of laser images. This reduction in the amount of image data to be processed significantly improves the frame rate of the area array image sensor, reaching its highest frame rate when each region of interest contains only one row of pixels. Similarly, with this relative positional relationship between the image sensor and the laser image signal, dynamic ROI operations are no longer necessary, and the microscope focusing device can maintain the maximum defocus sampling rate in both near-focus and far-focus states. Example 2

[0048] Another aspect of the present invention provides a sensor image acquisition device for acquiring a semi-elliptical laser image projected on the surface of an object to be measured in an autofocus system to calculate the defocus amount corresponding to the laser image. The device comprises: At least two linear array sensors, used for sampling points according to a preset defocus amount and dispersively collecting data from at least two areas in the long axis direction of the laser image; At least two one-dimensional optical fiber arrays are arranged along the long axis of the laser image and perpendicular to the long axis of the laser image, and are used to transmit image information of each defocus sampling point along the long axis of the laser image to the linear array sensor. The area where the linear array sensor collects the laser image is expanded by adjusting the spacing between the one-dimensional optical fiber arrays. A holder is used to independently fix the input ends of the one-dimensional optical fiber array at preset intervals to correspond to the defocus sampling points, and to align and couple the output ends of the one-dimensional optical fiber array with the corresponding linear array sensor; The linear array sensor is a single-row pixel linear array image sensor, and the defocus amount corresponding to the laser image is calculated by analyzing the defocus amounts of valid sampling points among all defocus amount sampling points.

[0049] In order to fully capture laser image signals with a length of millimeters, a conventional multi-line array image sensor, such as a typical line array image sensor with 2K resolution, 256 lines, and 3.5um pixel size, can only cover laser images of less than 1mm in length, resulting in partial signal loss. Moreover, the computational complexity is too large to simultaneously sample the defocus amount of 256 light-sensitive lines at a frequency of 10kHz. To address the problem of insufficient sampling area of ​​this multi-line array image sensor, a line array image sensor encapsulated with several sparsely spaced light-sensitive lines can be used for processing, where the light-sensitive line interval is D_line. K light-sensitive lines can sample laser image signals with a length of (K-1)×D_line, and D_line can be adjusted to adapt to laser lines of different lengths. However, this special line array image sensor usually needs to be customized. The present invention is based on a two-dimensional transmission fiber array and several single-line array image sensors spliced ​​into a multi-line array image sensor. The single-line array image sensor is a single-row pixel array image sensor, specifically as follows: like Figure 7 As shown, a two-dimensional optical fiber array is used to relay the laser image signal at the focal plane of the focusing lens in the optical path of the laser focus sensor to multiple independent single-line array image sensors at the back end.

[0050] First, a two-dimensional fiber array is formed by splicing K one-dimensional fiber arrays FA_i, i = 1, 2, ..., K. Each FA_i consists of N fibers with a core diameter of several microns. f N adjacent optical fibers are spliced ​​together. fThe larger the value, the stronger the far-focus laser image signal that can be collected, and the larger the focusing range of the laser focus sensor. As a specific embodiment of the present invention, each one-dimensional optical fiber array is evenly spaced along the long axis of the laser image to uniformly collect image information of the laser image.

[0051] K one-dimensional fiber arrays correspond to K defocus sampling points. When the number of sampling points is constant, the uniformity and integrity of the laser line signal sampling can be guaranteed by adjusting the interval D_line of the one-dimensional fiber array so that (K-1)×D_line is equal to the length of the laser image.

[0052] After the laser image signal is collected at the inlet of K one-dimensional fiber arrays, it is segmented and sampled, and then flexibly transmitted to K single-line array image sensors at the back end via a fiber bundle assembly. The outlet of the i-th one-dimensional fiber array FA_i is directly aligned and coupled with the light-sensitive line of the single-line array image sensor LS_i. This coupling method involves mechanically limiting alignment and fixation, using a mechanical three-axis adjustment structure to pre-align the light-sensitive line, and then bonding the FA_i outlet to the linear array image sensor package. Because defocus signal extraction only requires the centroid coordinates of the laser image signal's illumination distribution, not image details, precise alignment of the fiber array outlet of FA_i and the light-sensitive line of the linear array image sensor LS_i within the pixel size is not required. Lateral offsets of a few pixels have no significant impact on image signal processing.

[0053] The fixer is divided into a first fixing component and a second fixing component. The first fixing component is used to independently fix the input end of the one-dimensional optical fiber array to correspond to the defocus sampling point. For example, it includes several independently arranged adjustable substrates. The adjustable substrates have several optical fiber grooves or holes for installing optical fibers arrayed in a straight line direction. The optical fibers can be fixed by clamping or bonding so that the optical fibers are aligned with the defocus sampling point, such as perpendicular to the image area corresponding to the defocus sampling point; the second fixing component is used to complete the alignment and coupling of the output end of the one-dimensional optical fiber array with the corresponding linear array sensor. For example, the output end of the one-dimensional optical fiber array can be aligned with the corresponding linear array sensor and then packaged and bonded to achieve alignment and coupling.

[0054] After the K single-line array image sensors LS_i synchronously complete the acquisition of the segmented laser image signals, the back-end image processing chip calculates the K defocus signals. The calculation can also be performed by a host computer, manually, or by other computing entities. The specific calculation algorithm refers to the description of the above analysis method.

[0055] As a specific embodiment of the present invention, analyzing the defocus amounts of valid sampling points among all defocus amount sampling points includes: Collecting sampling data of the corresponding areas of each one-dimensional optical fiber array in groups to correspond to a number of defocus sampling points respectively; Filtering valid data from all sampled data to obtain a number of valid sampling points, and calculating the defocus amount corresponding to each valid sampling point; The standard deviation of the defocus values ​​at the valid sampling points is analyzed, and several valid defocus values ​​are screened to output the final defocus value.

[0056] By aligning and coupling several independently set one-dimensional optical fiber arrays with corresponding single-line linear array image sensors, sampling can be adaptively adjusted according to the length of the laser image. This not only solves the problem of insufficient sampling area of ​​traditional multi-line linear array image sensors, but also effectively combines the characteristic advantages of multi-line linear array sensors to improve the defocus sampling rate. Example 3

[0057] Another aspect of the present invention provides a map collecting device, comprising: Such as the above-mentioned map collection device; The lens is arranged in front of the one-dimensional optical fiber array along the light propagation path. Example 4

[0058] like Figure 8 As shown, the present invention further provides a high-speed image signal analysis system, comprising: A posture adjustment module is used to adjust the posture of the sensor until several sensitive light lines of the sensor are perpendicular to the long axis direction of the laser image, so that the image data collected by the sensitive light lines can be directly used as sampling data; A grouping acquisition module is used to collect sampling data of different areas of the laser image along the long axis in groups, so as to correspond to a number of defocus sampling points respectively; The effective analysis module is used to screen the effective data from all the sampled data to obtain a number of effective sampling points, so as to calculate the defocus value corresponding to each effective sampling point; The defocus analysis module is used to analyze the standard deviation of the defocus values ​​of the valid sampling points and screen out a number of valid defocus values ​​to output the final defocus value. Example 5

[0059] Another aspect of the present invention provides a computer-readable storage medium comprising a computer program, wherein the computer program implements the above-mentioned analysis method when executed by a processor.

[0060] In practical applications, computer-readable storage media may take the form of any combination of one or more computer-readable media. Computer-readable media may be computer-readable signal media or computer-readable storage media. Computer-readable storage media may be, but are not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or components, or any combination thereof. More specific examples of computer-readable storage media may include: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In this embodiment, a computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, device, or component.

[0061] A computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, which carries computer-readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium that can transmit, propagate, or transport a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0062] Program code embodied on a computer readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

[0063] Computer program code for performing the operations of the present application may be written in one or more programming languages, or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a stand-alone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0064] Throughout this specification, references to terms such as "one embodiment," "example," and "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0065] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention, and such changes and modifications fall within the scope of the invention as claimed.

Claims

1. A sensor image acquisition device for acquiring a semi-elliptical laser image projected on the surface of an object to be measured in an autofocus system to calculate the defocus amount corresponding to the laser image, characterized in that: The device comprises: At least two linear array sensors are used to collect samples of at least two areas in the long axis direction of the laser image according to preset defocus amount sampling points; At least two one-dimensional optical fiber arrays are arranged along the long axis direction of the laser image and perpendicular to the long axis of the laser image, and are used to transmit the image information of each defocus amount sampling point in the long axis direction of the laser image to the linear array sensor, and the area for collecting the laser image by the linear array sensor is expanded by adjusting the spacing between the one-dimensional optical fiber arrays; A fixture is used to independently fix the input ends of the one-dimensional optical fiber array at preset intervals to correspond to the defocus amount sampling points, and to align and couple the output ends of the one-dimensional optical fiber array with the corresponding linear array sensor; Wherein, the linear array sensor is a single-row pixel linear array image sensor, and the defocus amount corresponding to the laser image is calculated by analyzing the defocus amounts of effective sampling points among all defocus amount sampling points.

2. A sensor image acquisition device according to claim 1, characterized in that: Each one-dimensional optical fiber array is distributed at equal intervals along the long axis direction of the laser image to uniformly collect image information of the laser image.

3. A sensor image acquisition device according to claim 1, characterized in that: The output end of each one-dimensional optical fiber array is aligned with its corresponding linear array sensor and coupled through packaging and bonding.

4. A sensor image acquisition device according to any one of claims 1 to 3, characterized in that: Analyze the defocus of valid sampling points in all defocus sampling points, including: Collecting sampling data of the corresponding areas of each one-dimensional optical fiber array in groups to correspond to a number of defocus amount sampling points respectively; Filter valid data from all sampled data to obtain a number of valid sampling points, so as to calculate the defocus amount corresponding to each valid sampling point; The standard deviation of the defocus values ​​at the effective sampling points is analyzed, and several effective defocus values ​​are screened to output the final defocus value.

5. A sensor image acquisition device according to claim 4, characterized in that: After collecting the sampling data of different areas of the laser image along the long axis direction in groups, when reading the sampling data corresponding to the current area, it is synchronously analyzed whether the sampling data corresponding to the previous area is valid data.

6. A sensor image acquisition device according to claim 4, characterized in that: The valid data analysis method includes: calculating the maximum grayscale value in each group of sampled data to analyze whether the maximum grayscale value is greater than a grayscale threshold, and if so, it is judged as valid data, otherwise it is invalid data.

7. A sensor image acquisition device according to claim 6, characterized in that: The defocus amount corresponding to each valid sampling point is obtained by calculating the offset between the grayscale centroid of each valid sampling point and the focus reference zero point.

8. A sensor image acquisition device according to claim 7, characterized in that: The effective defocus amount is the defocus amount of the effective sampling points within the corresponding range of the standard deviation.

9. A sensor image acquisition device according to claim 8, characterized in that: The final defocus value is the average of all valid defocus values.

10. A map collecting device, characterized in that: include: The image acquisition device according to any one of claims 1 to 9; The lens is arranged in front of the one-dimensional optical fiber array along the light propagation path.

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