Apparatus and testing methods for camera module performance testing

Abstract

This application provides an apparatus and method for testing the performance of camera modules. The apparatus includes: a position correction platform, a first rotating axis, a fixed plate, a second rotating axis, a column, a cantilever, a lead screw, a collimator, and a test chart including a transparent annular area. The position correction platform is horizontally fixed, with the first rotating axis vertically mounted at its center and the second rotating axis horizontally mounted on its outer side; the fixed plate is horizontally mounted on the upper end of the first rotating axis; one end of the column is vertically fixed to the outer end of the second rotating axis, and the cantilever is fixed to the other end of the column through the horizontal mounting slot; the collimator is vertically fixed to the other end of the cantilever; one end of the lead screw is connected to the test chart built into the collimator. By processing the same captured image using this apparatus, the SFR resolution and Flare glare tests of wide-angle and / or telephoto camera modules with corresponding FOV and focal length can be completed, simplifying the testing process, reducing testing costs, and improving testing efficiency.

Description

Technical Field

[0001] This application relates to the field of camera module testing technology, and in particular to a technology for testing the performance of camera modules. Background Art

[0002] ADAS (Advanced Driver Assistance System) utilizes various sensors installed in automobiles, such as cameras, radar, lasers, and ultrasonic sensors, to collect environmental data inside and outside the vehicle in real time. This data is processed through techniques such as identifying, detecting, and tracking static and dynamic objects, enabling drivers to detect potential dangers as quickly as possible, thus raising their awareness and improving safety. Benefiting from the development of automotive intelligence, ADAS technology has rapidly developed and been widely adopted. Active intervention during driving is becoming increasingly common, leading to a greater demand for camera modules. Generally, a complete ADAS system deployed in a car requires at least six wide-angle and / or telephoto camera modules (1 front-view + 1 rear-view + 4 surround-view) to collect data on the external environment.

[0003] The resolution of a camera module refers to its ability to reproduce details of the subject. If the resolution is low, even with a high-resolution camera module, the captured image will still be blurry. Resolution performance can be evaluated using metrics such as SFR (Spatial Frequency Response) or MTF (Modulation Transfer Function). Glare is a visual phenomenon that occurs when the light source is extremely bright or when there is a large difference in brightness between the background and the center of the field of view. Glare not only hinders viewing but also affects eyesight and can easily cause visual fatigue. Therefore, the resolution and glare performance of wide-angle and / or telephoto camera modules used in ADAS must meet the required standards.

[0004] In one existing resolution testing method, a rectangular patterned planar test chart is used as the test object, and a collimator is used as the light source. An image including the black-and-white boundary diagonal line area is captured. Software conforming to relevant resolution testing standards processes the black-and-white boundary diagonal line area in the image and calculates the SFR value. Traditional Flare testing uses two methods: one is the ISO 18844 scheme, using a radial dot matrix patterned test chart as the test object and a collimator as the light source. For camera modules with a relatively small FOV (Field of View) (e.g., FOV < 130°), a planar test chart can be used. However, for camera modules with a larger FOV, a curved test chart is usually required based on the lens parameters of the camera module. Another method uses the ISO 9358 scheme, employing a single light source that can move along an arc centered on the center of the camera module's lens. After capturing the image, software conforming to relevant glare performance testing standards processes and calculates the bright areas in the image, and the glare performance can be evaluated based on the calculation results.

[0005] Currently, the resolution performance test and glare performance test of camera modules are completed by obtaining different images in different test environments and then processing the images, rather than using the same image. Summary of the Invention

[0006] The purpose of this application is to provide an apparatus and method for testing the performance of camera modules, so as to process the same image captured by the apparatus to complete the resolution performance test and glare performance test of wide-angle and / or telephoto camera modules.

[0007] One embodiment of this application provides an apparatus for testing the performance of a camera module, wherein the apparatus includes:

[0008] The position correction platform includes a first rotating axis, a fixed plate, a second rotating axis, a column, a cantilever, a lead screw, a collimator, and a test chart with a circular transparent area, wherein the light transmission contrast between the transparent and opaque areas in the test chart meets a preset value.

[0009] The position correction platform is fixed horizontally, the first rotating shaft is vertically installed at the center of the position correction platform, and the second rotating shaft is horizontally installed on the outside of the position correction platform.

[0010] A fixing plate is horizontally mounted on the upper end of the first rotating shaft, wherein the fixing plate is provided with a fixing device for horizontally fixing the camera module;

[0011] One end of the column is vertically fixed to the outer end of the second rotating shaft, and one end of the cantilever is provided with a horizontal mounting slot. The cantilever is fixed to the other end of the column through the horizontal mounting slot.

[0012] The parallel light tube is vertically fixed to the other end of the cantilever.

[0013] One end of the lead screw is connected to the test chart card built into the collimator.

[0014] Optionally, the device further includes:

[0015] The controller, the first motor, the second motor, and the third motor, wherein,

[0016] The controller is electrically connected to the first motor, the second motor, and the third motor, respectively;

[0017] The first motor is connected to the first rotating shaft via a transmission, and is used to drive the first rotating shaft to rotate horizontally;

[0018] The second motor is connected to the second rotating shaft via a transmission, and is used to drive the second rotating shaft to rotate vertically;

[0019] The third motor is connected to the lead screw drive and is used to drive the lead screw to move the test chart inside the parallel light tube vertically.

[0020] Optionally, the device further includes:

[0021] An image processing unit, electrically connected to the camera module, is used to process the first image corresponding to the test chart captured by the camera module to complete the glare test of the camera module, wherein the first image includes a bright area in a circular shape corresponding to the transparent area in a circular shape.

[0022] Optionally, the image processing unit is further configured to process the first image to complete the resolution test of the camera module.

[0023] Another embodiment of this application provides a method for testing the performance of a camera module, using the aforementioned apparatus, wherein the method includes:

[0024] The camera module is fixed on the fixing plate of the position correction platform. Based on the field of view and focal length of the camera module, the position of the test pattern card including the transparent area in the annular shape in the collimator and the position of the collimator relative to the camera module are set.

[0025] Capture a first image corresponding to the test chart, wherein the first image includes a bright area corresponding to the transparent area of ​​the annular shape;

[0026] Determine the centroid of the bright region in the first image, and based on the centroid, fit a circular bright region, and determine the radius of the inner and outer circles of the circular bright region;

[0027] The first image is subjected to grayscale processing and Gamma enhancement processing to obtain the second image;

[0028] Based on the radii of the inner and outer circles within the annular bright area in the second image, determine the area of ​​the annular bright area and the area and / or length of the brightness abrupt portion in the bright area outside it;

[0029] Calculate the ratio of the area of ​​the brightness abrupt change portion in the bright region outside the annular bright region to the area of ​​the annular bright region, and compare the ratio with a first preset threshold, and / or compare the length of the brightness abrupt change portion in the bright region outside the annular bright region with a second preset threshold, in order to determine whether the camera module has glare.

[0030] Optionally, the method further includes:

[0031] Based on the radius of the outer circle of the annular bright area in the first image, several points on the edge contour of the outer circle of the annular bright area are determined, and each point is taken as the center point of a ROI region.

[0032] Based on the center point of each ROI region and preset ROI parameters, several ROI regions are determined, and based on the several ROI regions, the SFR value of the camera module is calculated.

[0033] This application provides an apparatus and method for testing the performance of a camera module. The apparatus includes: a position correction platform, a first rotating axis, a fixed plate, a second rotating axis, a column, a cantilever, a lead screw, a collimator, and a test chart including a transparent annular area. The steps for performing performance testing of a camera module based on this device include: fixing the camera module on a fixed plate of a position correction platform; setting the position of a test chart including a transparent annular region in a collimator and the position of the collimator relative to the camera module according to the field of view and focal length of the camera module; capturing a first image corresponding to the test chart, wherein the first image includes a bright region corresponding to the transparent annular region; determining the centroid of the bright region in the first image, and fitting a circular bright region based on the centroid, and determining the radius of the inner and outer circles of the circular bright region; performing grayscale processing and Gamma enhancement processing on the first image to obtain a second image; determining the area of ​​the circular bright region and the area and / or length of the brightness abrupt change portion in the bright region outside the circular bright region based on the radius of the inner and outer circles of the circular bright region in the second image; calculating the ratio of the area of ​​the brightness abrupt change portion in the bright region outside the circular bright region to the area of ​​the circular bright region, and comparing the ratio with a first preset threshold, and / or comparing the length of the brightness abrupt change portion in the bright region outside the circular bright region with a second preset threshold to determine whether the camera module has glare. Optionally, the method further includes: determining several points on the edge contour of the outer circle of the annular bright area in the first image based on the radius of the outer circle, and taking each point as the center point of a Region of Interest (ROI); determining several ROI regions based on the center point of each ROI region and preset ROI parameters; and calculating the SFR value of the camera module based on the several ROI regions. Through this device and the above steps, processing the same image captured under the same test environment can complete the SFR resolution and Flare glare tests of wide-angle and / or telephoto camera modules with corresponding FOV and focal length. This integrates existing two or more separate camera module performance testing environments and methods, simplifies the testing process, reduces testing costs, and improves testing efficiency. Attached Figure Description

[0034] Other features, objects, and advantages of the invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0035] Figure 1 This illustration shows a schematic diagram of a device structure for testing the performance of a camera module according to an embodiment of this application;

[0036] Figure 2This illustration shows a test chart pattern for camera module performance testing according to an embodiment of this application;

[0037] Figure 3 This illustration shows a structural diagram of a camera module performance test at different field of view angles according to an embodiment of this application.

[0038] Figure 4 This illustration shows a flowchart of a method for testing the performance of a camera module according to another embodiment of this application.

[0039] Figure 5 This illustration shows a flowchart of a method for testing the performance of a camera module, representing an alternative embodiment of another embodiment of this application.

[0040] In the accompanying drawings, the same or similar reference numerals represent the same or similar parts. For the sake of simplicity, the parts shown in each drawing are schematic representations of the parts relevant to the invention and do not represent their actual structure as a product.

[0041] In addition, to make the drawings concise and easy to understand, some drawings may only schematically indicate one of the components that have the same structure or function. DETAILED DESCRIPTION

[0042] The present invention will now be described in further detail with reference to the accompanying drawings.

[0043] Benefiting from the development of automotive intelligence, more and more cars are equipped with ADAS. Camera modules with wide-angle and / or telephoto lenses are usually deployed at the front, sides and rear of the car to collect images of the external environment around the car and provide them to ADAS to achieve driving and parking assistance. Therefore, the performance of the camera module must meet the requirements, including the resolution performance and glare performance of the camera module.

[0044] One existing method for testing the resolution of wide-angle and / or telephoto camera modules used in ADAS typically uses a planar test chart with a rectangular pattern as the test object and a collimator as the light source to capture an image including the black-and-white boundary diagonal line area. Then, relevant software processes the black-and-white boundary diagonal line area in the image and calculates the SFR value to evaluate the resolution performance of the camera module. Traditional Flare testing uses two methods: one is the ISO 18844 scheme, which uses a test chart with a radial dot matrix pattern as the test object and a collimator as the light source. For camera modules with a small field of view (FOV), such as FOV < 130°, a planar test chart can be used. However, for camera modules with a large FOV, a curved test chart is usually required based on the lens parameters of the camera module. Another method is the ISO 9358 scheme, which uses a single light source that can move along an arc centered on the center of the camera module's lens. The light source moves along the arc to the appropriate position according to the FOV of the camera module and then captures an image of the curved test chart. Relevant software is used to process and calculate bright areas in the image, and the glare performance can be evaluated based on the calculation results. Since the environment used for testing the resolution performance of the camera module differs from that used for testing glare performance, different testing environments need to be deployed to conduct the relevant performance tests. This process is complex, time-consuming, and inefficient.

[0045] This application provides a technical solution for testing the performance of camera modules. It can process and calculate images captured under the same test environment, evaluate the glare performance of the camera module based on the calculation results, and process and calculate the same image to obtain the SFR value.

[0046] To further illustrate the technical means adopted and the effects achieved in this application, the technical solution of this application will be clearly and completely described below in conjunction with the accompanying drawings and preferred embodiments.

[0047] Figure 1 This application illustrates an apparatus for testing the performance of a camera module according to one embodiment, wherein the apparatus includes:

[0048] The position correction platform 1, the first rotating axis 2, the fixed plate 3, the second rotating axis 4, the column 5, the cantilever 6, the lead screw 7, the parallel light tube 8, and the test chart 9 including a transparent area in the shape of a ring, wherein the light transmission contrast between the transparent area and the opaque area in the test chart 9 meets a preset value;

[0049] The position correction platform 1 is fixed horizontally, the first rotating shaft 2 is vertically installed at the center of the position correction platform 1, and the second rotating shaft 4 is horizontally installed on the outside of the position correction platform 1.

[0050] A fixing plate 3 is horizontally mounted on the upper end of the first rotating shaft 2, wherein the fixing plate 3 is provided with a fixing device for horizontally fixing the camera module;

[0051] One end of the column 5 is vertically fixed to the outer end of the second rotating shaft 4, and one end of the cantilever 6 is provided with a horizontal mounting slot. The cantilever 6 is fixed to the other end of the column 5 through the horizontal mounting slot.

[0052] The parallel light tube 8 is vertically fixed to the other end of the cantilever 6;

[0053] One end of the lead screw 7 is connected to the test chart 9 built into the collimator.

[0054] In this embodiment, the camera module is first horizontally fixed to the fixing plate 3 by a fixing device on the fixing plate 3. The fixing device can be a spring-loaded plate or a device that achieves fixation through the cooperation of positioning holes and fixing bolts / screws. This is merely an example and does not limit the specific form of the fixing device. Other existing or future fixing devices that are applicable to this application should also be included within the scope of protection of this application. The cantilever 6 can be adjusted to fix its position to the column 5 through a horizontal slot. Then, the cantilever 6 is fixed to the other end of the column 5 so that the center or other position of the annular pattern of the test pattern card in the collimator 8 is aligned with the center of the lens of the camera module under test on the same axis. Based on the field of view and focal length parameters of the camera module under test, the first rotating shaft 2, the second rotating shaft 4, and the lead screw 7 are adjusted to set the position of the test pattern card 9 in the collimator 8 and the position of the collimator 8 relative to the camera module under test. The test pattern card 9, including the annular transparent area, is as follows: Figure 2 As shown, the light transmission contrast between the transparent and opaque areas should meet a preset value. For example, the light transmission contrast between the transparent and opaque areas of the pattern in test chart 9 should not be less than 40. The camera module under test can be rotated clockwise or counterclockwise on the horizontal plane via the first rotation axis 2 to meet different field-of-view testing requirements, such as the upper left or lower right positions of the pattern in the test chart. The column 5 can be rotated left or right on the vertical plane via the second rotation axis 4 to meet different field-of-view requirements, such as... Figure 3As shown, for example, if the FOV of the camera module under test is 130°, the collimator 8 can be rotated left and right within a 130° range on the vertical plane via the second rotating axis 4, taking pictures at different positions corresponding to different FOVs to obtain corresponding images. Then, by analyzing the bright areas in the images, the resolution and glare performance of the camera module under test at different field of view angles within the 130° range can be obtained. The test chart 9 can be adjusted up or down on the vertical plane inside the collimator 8 via the lead screw 7 to meet different focal length requirements and simulate the test object at different positions (it can simulate the test object from 4 cm to infinity away from the lens of the camera module under test). Then, the camera module under test takes pictures of the test chart 9 in the collimator 8 to obtain the first images taken by the wide-angle and / or telephoto camera modules at different field of view angles and / or focal lengths.

[0055] The scale can be marked at appropriate positions on the end faces of the position correction platform 1, the first rotating shaft 2 and the second rotating shaft 4, the lead screw 7 and / or related components to assist in the above adjustments.

[0056] In an optional embodiment, the device further includes:

[0057] Controller 10, first motor 11, second motor 12 and third motor 13, wherein,

[0058] The controller 10 is electrically connected to the first motor 11, the second motor 12 and the third motor 13 respectively;

[0059] The first motor 11 is connected to the first rotating shaft 2 for driving the first rotating shaft 2 to rotate horizontally;

[0060] The second motor 12 is connected to the second rotating shaft 4 for driving the second rotating shaft 4 to rotate vertically;

[0061] The third motor 13 is connected to the lead screw 7 and is used to drive the lead screw 7 to move the test chart 9 inside the parallel light tube vertically.

[0062] In this optional embodiment, the controller 10 can also control different high-precision motors to drive the first rotating shaft 2, the second rotating shaft 4 and the lead screw 7 respectively, so as to realize the alignment of the camera module under test with the collimator 8, determine the position of the collimator 8 relative to the camera under test and the position of the test chart 9 respectively.

[0063] In an optional embodiment, the device further includes:

[0064] The image processing unit 15 is electrically connected to the camera module and is used to process the first image corresponding to the test chart 9 captured by the camera module to complete the glare test of the camera module. The first image includes a bright area in a circular shape corresponding to the transparent area in a circular shape.

[0065] The camera module under test is also electrically connected to the image processing unit 15, which transmits the captured first image to the image processing unit 15. The image processing unit 15 processes the first image, and the processing result can be used to evaluate the glare performance of the camera module.

[0066] In an optional embodiment, the image processing unit 15 is further configured to process the first image to complete the resolution test of the camera module.

[0067] The image processing unit 15 further processes the first image to obtain an SFR value used to evaluate the resolution performance of the camera module.

[0068] Figure 4 This application illustrates another embodiment of a method for testing camera performance, employing the apparatus described in the above embodiment, wherein the method includes:

[0069] S201 fixes the camera module on the fixing plate of the position correction platform. Based on the field of view and focal length of the camera module, the position of the test pattern card including the transparent area in the annular shape in the collimator and the position of the collimator relative to the camera module are set.

[0070] S202 captures a first image corresponding to the test chart, wherein the first image includes a bright area corresponding to the transparent area of ​​the annular shape;

[0071] S203 determines the centroid of the bright region of the first image, and based on the centroid, fits a circular bright region, and determines the radius of the inner and outer circles of the circular bright region;

[0072] S204 performs grayscale processing and Gamma enhancement processing on the first image to obtain the second image;

[0073] S205 determines the area of ​​the annular bright region and the area and / or length of the brightness abrupt portion in the bright region outside it based on the radii of the inner and outer circles of the annular bright region in the second image;

[0074] S206 calculates the ratio of the area of ​​the brightness abrupt change portion in the bright region outside the annular bright region to the area of ​​the annular bright region, and compares the ratio with a first preset threshold, and / or compares the length of the brightness abrupt change portion in the bright region outside the annular bright region with a second preset threshold, in order to determine whether the camera module has glare.

[0075] The method embodiments employ the apparatus described in the above-described apparatus embodiments.

[0076] In this embodiment of the method, in step S201, the camera module is first horizontally fixed on the fixing plate 3, and then the horizontal slot of the cantilever 6 and the fixing position of the other end of the column 5 are adjusted so that the collimator 8 and the lens center of the camera module to be tested are aligned on the same axis. Then, according to the field of view and focal length parameters of the camera module to be tested, the first rotating axis 2, the second rotating axis 4 and the lead screw 7 are adjusted to set the position of the test chart 9 including the annular transparent area in the collimator 8 and the position of the collimator 8 relative to the camera module to be tested.

[0077] In this embodiment of the method, in step S202, the camera module under test takes a picture of the test pattern card 9 in the collimator 8 to obtain a corresponding first image, which is then sent to the image processing unit 15. The first image includes a bright area corresponding to the transparent ring-shaped area in the test pattern card 9.

[0078] Referring to the ISO18844 test scheme, the image processing unit 15 can determine whether there is glare by determining the brightness difference between the bright area and the surrounding area in the first image, so as to realize the glare performance test of the camera module under test.

[0079] Continuing in this method embodiment, in step S203, the image processing unit 15 determines the centroid of the bright area of ​​the first image, and based on the centroid, fits a circular bright area, and determines the radius of the inner and outer circles of the circular bright area.

[0080] In this embodiment of the method, in step S204, the image processing unit 15 performs grayscale processing and Gamma enhancement processing on the first image to obtain a second image.

[0081] Specifically, based on the centroid of the bright region in the first image, the fitted annular bright region, and the radii of its inner and outer circles, the corresponding annular bright region and the radii of its inner and outer circles in the second image can be determined.

[0082] Continuing in this method embodiment, in step S205, the image processing unit 15 can calculate the area of ​​the annular bright area and the area and length of the brightness abrupt change portion in the bright area outside it based on the radius of the inner and outer circles of the annular bright area in the second image.

[0083] Continuing in this method embodiment, in step S206, the image processing unit 15 calculates the ratio of the area of ​​the brightness abrupt change portion in the bright region outside the annular bright region to the area of ​​the calculated annular bright region, and compares the calculated ratio with a first preset threshold. If the ratio is greater than the first preset threshold, it can be considered that there is glare in the brightness abrupt change portion in the bright region outside the annular bright region; or it compares the length of the brightness abrupt change portion in the bright region outside the annular bright region with a second preset threshold. If the length is greater than the second preset threshold, it can be considered that there is glare in the brightness abrupt change portion in the bright region outside the annular bright region; or both can be used simultaneously for judgment, that is, if the ratio of the area of ​​the brightness abrupt change portion in the bright region outside the annular bright region to the area of ​​the calculated annular bright region is greater than the first preset threshold, and the length of the brightness abrupt change portion in the bright region outside the annular bright region is greater than the second preset threshold, then it is considered that there is glare in the brightness abrupt change portion in the bright region outside the annular bright region.

[0084] An optional implementation, for example Figure 5 As shown, in this optional embodiment, in addition to steps S201 to S206 of the above embodiment, the method further includes the following steps:

[0085] S207 Based on the radius of the outer circle of the annular bright area in the first image, determine several points on the edge contour of the outer circle of the annular bright area, and take each point as the center point of a ROI region;

[0086] S208 determines several ROI regions based on the center point of each ROI region and preset ROI parameters, and calculates the SFR value of the camera module based on the several ROI regions.

[0087] In this optional embodiment, in step S207, the image processing unit 15 determines several points on the outer circle shape edge contour of the annular bright area based on the calculated radius of the outer circle of the annular bright area in the first image, and uses each point as the center point of a ROI region.

[0088] Continuing in this optional embodiment, in step S208, the image processing unit 15 can use the center point of each ROI region as the center of a circle, and determine several circular ROI regions according to preset ROI parameters. Then, oversampled edge diffusion is performed on each pixel within each circular ROI region. That is, by calculating the distance between each pixel within the ROI region and the centroid of the circular bright region, and rearranging the pixel values ​​based on the distance between each pixel and the centroid of the circular bright region, the relationship between the pixel value and the distance can be obtained. Then, the oversampled edge diffusion is averaged onto the same oblique edge diffusion function to obtain the ESF (Edge Spread Function). The ESF is then differentiated to obtain the LSF (Line Spread Function). To reduce the influence of high-frequency noise and avoid frequency leakage caused by the discontinuity at both ends (start and end) of the curve obtained by directly performing DFT (Discrete Fourier Transform) operations, a Hamming window can be applied to the LSF for windowing operations. Finally, a DFT operation is performed, and the SFR value can be obtained from the result. Compared with the existing oblique edge method for calculating SFR values, this method can directly process and calculate the SFR value for images with large distortion at the edges of bright regions, without requiring the edges of bright regions to include oblique straight edges.

[0089] In this optional embodiment, the image processing unit 15 processes the first images captured by the camera module under test with different FOVs and / or different focal lengths to finally obtain the resolution performance and glare performance of the camera module under test with different FOVs and / or different focal lengths.

[0090] The above-described processing steps for the first image can be written into a software tool using C++ or other languages. The software tool can then be used to process the first image to obtain the SFR value and glare performance.

[0091] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be embraced within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims. Furthermore, it is clear that the word "comprising" does not exclude other units or steps, and the singular does not exclude the plural. Multiple units or devices recited in the apparatus claims may also be implemented by a single unit or device through software and / or hardware. The terms "first," "second," etc., are used to indicate names and do not indicate any particular order.

Claims

1. A method for testing the performance of a camera module, based on a device, characterized in that, The device includes: a position correction platform, a first rotating shaft, a fixed plate, a second rotating shaft, a column, a cantilever, a lead screw, a collimator, a test chart including a circular transparent area, and an image processing unit; wherein, the light transmission contrast between the transparent and opaque areas in the test chart meets a preset value; the position correction platform is horizontally fixed, the first rotating shaft is vertically installed at the center of the position correction platform, and the second rotating shaft is horizontally installed on the outer side of the position correction platform; a fixed plate is horizontally installed at the upper end of the first rotating shaft, wherein the fixed plate is provided with a horizontal fixing mechanism. A fixing device for the fixed camera module; one end of the column is vertically fixed to the outer end of the second rotating shaft, one end of the cantilever is provided with a horizontal mounting slot, and the cantilever is fixed to the other end of the column through the horizontal mounting slot; the collimator is vertically fixed to the other end of the cantilever; one end of the lead screw is connected to the test pattern card built into the collimator; the image processing unit is electrically connected to the camera module and is used to process the first image corresponding to the test pattern card captured by the camera module, wherein the first image includes a bright area in a circular shape corresponding to the transparent area in a circular shape; The method includes: The camera module is fixed on the fixing plate of the position correction platform. Based on the field of view and focal length of the camera module, the position of the test chart card in the collimator and the position of the collimator relative to the camera module are set. Capture a first image corresponding to the test chart, wherein the first image includes a bright area corresponding to the transparent area of ​​the annular shape; Determine the centroid of the bright region in the first image, and based on the centroid, fit a circular bright region, and determine the radius of the inner and outer circles of the circular bright region; The first image is subjected to grayscale processing and Gamma enhancement processing to obtain the second image; Based on the radii of the inner and outer circles within the annular bright area in the second image, determine the area of ​​the annular bright area and the area and / or length of the brightness abrupt portion in the bright area outside it; Calculate the ratio of the area of ​​the brightness abrupt change portion in the bright region outside the annular bright region to the area of ​​the annular bright region, and compare the ratio with a first preset threshold, and / or compare the length of the brightness abrupt change portion in the bright region outside the annular bright region with a second preset threshold, in order to determine whether the camera module has glare.

2. The method according to claim 1, characterized in that, The method further includes: Based on the radius of the outer circle of the annular bright area in the first image, several points on the edge contour of the outer circle of the annular bright area are determined, and each point is taken as the center point of a ROI region. Based on the center point of each ROI region and preset ROI parameters, several ROI regions are determined, and based on the several ROI regions, the SFR value of the camera module is calculated.

Images