A method, system and related device for measuring chromatic aberration of camera lens module

Abstract

The present application discloses a method, system and related device for measuring the chromatic aberration of a camera lens module, which are used to realize quantitative analysis of the chromatic aberration of the lens and improve the chromatic aberration measurement efficiency of the camera lens module. The present application method includes: arranging a camera lens module, a multi-color backlight plate and a resolution plate; controlling the multi-color backlight plate to switch to a white light source, and adjusting the exposure setting of the camera lens module to adjust the grayscale of the target area to a preset grayscale; shooting a first image of the resolution plate through the camera lens module to obtain a first MTF value of the first image; sequentially controlling the multi-color backlight plate to switch to R, G, and B light sources, and adjusting the exposure setting of the camera lens module to adjust the grayscale of the target area to a preset grayscale; shooting a second image of the resolution plate through the camera lens module to obtain a second MTF value of the second image; determining the chromatic aberration of the camera lens module according to the first MTF value and the second MTF value.

Description

Technical Field

[0001] The present application relates to the field of optical technology, and in particular to a method, system and related device for measuring chromatic aberration of a camera lens module. Background Art

[0002] In the fields of optical measurement technology, camera imaging technology and image processing technology, the color difference measurement of camera lens modules is an important link. Since the lens has different refractive indices for different wavelengths of colored light, the color difference of the camera lens module refers to the phenomenon that during the imaging process, light of different wavelengths cannot be focused on the same focal point after passing through the lens, resulting in color stripes or blur at the edge of the image. Therefore, in the production and quality control process of camera lens modules, the measurement and control of color difference is the key to ensure image clarity and quality.

[0003] Existing methods for measuring camera lens module color difference mainly include determining whether the color difference meets the requirements through naked eye observation and empirical judgment, or using measurement tools such as ISO12233 test cards or dot charts, reflective light boxes, color temperature illuminance meters, special tripods, etc., and using specified software for image color difference analysis. Direct observation with the naked eye lacks objectivity and quantitative analysis methods, which to a certain extent affects the accuracy and reliability of the measurement results. The use of professional measurement tools requires professional personnel to operate, and the operation process is complicated and time-consuming, and requires the use of expensive measuring instruments and tools, which not only increases the test cost, but also limits its application in actual production, resulting in low efficiency in measuring camera lens module color difference. Summary of the invention

[0004] The present application provides a method, system and related device for measuring the chromatic aberration of a camera lens module, which are used to achieve quantitative analysis of the chromatic aberration of the lens and improve the chromatic aberration measurement efficiency of the camera lens module.

[0005] The first aspect of the present application provides a method for measuring chromatic aberration of a camera lens module, comprising:

[0006] Arrange the camera lens module, multi-color backlight board and resolution board;

[0007] Controlling the multi-color backlight panel to switch to a white light source, and adjusting the exposure setting of the camera lens module to adjust the grayscale of the target area to a preset grayscale;

[0008] photographing a first image of the resolution plate through the camera lens module, and acquiring a first MTF value of the first image;

[0009] Controlling the multi-color backlight panel to switch to R, G, and B light sources in sequence, and adjusting the exposure setting of the camera lens module to adjust the grayscale of the target area to the preset grayscale;

[0010] photographing a second image of the resolution plate through the camera lens module, and acquiring a second MTF value of the second image;

[0011] The chromatic aberration of the camera lens module is determined according to the first MTF value and the second MTF value.

[0012] Optionally, determining the chromatic aberration of the camera lens module according to the first MTF value and the second MTF value includes:

[0013] Calculating a difference between the first MTF value and the second MTF value, and determining a resolution difference level according to the difference;

[0014] It is determined whether the chromatic aberration of the camera lens module meets application requirements according to the resolution difference level.

[0015] Optionally, calculating the difference between the first MTF value and the second MTF value includes:

[0016] Determine the R, G, and B light source weighting coefficients according to the spectral response characteristics of the camera lens module;

[0017] The difference between the first MTF value and the second MTF value is calculated according to the R, G, B light source weighting coefficients.

[0018] Optionally, acquiring a first MTF value of the first image includes:

[0019] Determine a frequency region according to application requirements, wherein the frequency region includes a low frequency region and a high frequency region;

[0020] A first MTF value of the first image in the frequency region is obtained.

[0021] Optionally, the target area corresponds to a white area on the resolution panel, and the preset grayscale value is 210.

[0022] Optionally, the arrangement of the camera lens module, the multi-color backlight panel and the resolution panel includes:

[0023] Placing a multi-color backlight plate horizontally, using the multi-color backlight plate to evenly illuminate a resolution plate, and placing a camera lens module vertically above the resolution plate;

[0024] The camera lens module is controlled to move up and down so that the field of view of the camera lens module completely covers the resolution board.

[0025] Optionally, before photographing the first image of the resolution plate through the camera lens module, the method further includes:

[0026] The focal length of the camera lens module is adjusted to enable the camera lens module to produce a clear image.

[0027] A second aspect of the present application provides a system for measuring chromatic aberration of a camera lens module, comprising:

[0028] An arrangement unit, used for arranging a camera lens module, a multi-color backlight panel and a resolution panel;

[0029] A first control unit, used for controlling the multi-color backlight panel to switch to a white light source, and adjusting the exposure setting of the camera lens module to adjust the grayscale of the target area to a preset grayscale;

[0030] A first acquisition unit, configured to capture a first image of the resolution plate through the camera lens module, and acquire a first MTF value of the first image;

[0031] A second control unit is used to control the multi-color backlight panel to switch to R, G, and B light sources in sequence, and adjust the exposure setting of the camera lens module to adjust the grayscale of the target area to the preset grayscale;

[0032] A second acquisition unit, configured to capture a second image of the resolution plate through the camera lens module, and acquire a second MTF value of the second image;

[0033] A chromatic aberration determination unit is used to determine the chromatic aberration of the camera lens module according to the first MTF value and the second MTF value.

[0034] Optionally, the color difference determination unit is specifically used for:

[0035] Calculating a difference between the first MTF value and the second MTF value, and determining a resolution difference level according to the difference;

[0036] It is determined whether the chromatic aberration of the camera lens module meets application requirements according to the resolution difference level.

[0037] Optionally, the color difference determination unit is further configured to:

[0038] Determine the R, G, and B light source weighting coefficients according to the spectral response characteristics of the camera lens module;

[0039] The difference between the first MTF value and the second MTF value is calculated according to the R, G, B light source weighting coefficients.

[0040] Optionally, the first acquiring unit is specifically used for:

[0041] Determine a frequency region according to application requirements, wherein the frequency region includes a low frequency region and a high frequency region;

[0042] A first MTF value of the first image in the frequency region is obtained.

[0043] Optionally, the target area corresponds to a white area on the resolution panel, and the preset grayscale value is 210.

[0044] Optionally, the arrangement unit is specifically used for:

[0045] Placing a multi-color backlight plate horizontally, using the multi-color backlight plate to evenly illuminate a resolution plate, and placing a camera lens module vertically above the resolution plate;

[0046] The camera lens module is controlled to move up and down so that the field of view of the camera lens module completely covers the resolution board.

[0047] Optionally, the first acquiring unit is further used for:

[0048] The focal length of the camera lens module is adjusted to enable the camera lens module to produce a clear image.

[0049] A third aspect of the present application provides a device for measuring chromatic aberration of a camera lens module, the device comprising:

[0050] Processor, memory, input-output unit, and bus;

[0051] The processor is connected to the memory, the input and output unit, and the bus;

[0052] The memory stores a program, and the processor calls the program to execute the first aspect and any optional method for measuring the chromatic aberration of a camera lens module in the first aspect.

[0053] A fourth aspect of the present application provides a computer-readable storage medium, on which a program is stored. When the program is executed on a computer, the method for measuring the chromatic aberration of a camera lens module according to the first aspect and any optional method in the first aspect is executed.

[0054] It can be seen from the above technical solutions that this application has the following advantages:

[0055] By using a multi-color backlight panel and a resolution panel, and taking advantage of the different focal lengths of different colors of light focused on the camera sensor after passing through the lens, the MTF values ​​under white, red, green, and blue light sources are obtained, respectively, and the imaging differences of the camera lens under different color light sources can be clearly quantified. By comparing and analyzing the differences of these MTF values, the chromatic aberration of the lens can be clearly and quantitatively measured, and the chromatic aberration level of the lens can be judged based on the MTF changes under different color lights, making the measurement of chromatic aberration more accurate and intuitive, and the chromatic aberration of the lens can be quantitatively analyzed through the changes in the MTF value.

[0056] The entire measurement process only requires the use of a multi-color backlight panel and a resolution panel, without the need for complex instruments such as a reflective light source box and a resolution test card. This simplifies the operation process, makes the operation simpler and more convenient, reduces the measurement difficulty and cost, and greatly improves the color difference measurement efficiency of the camera lens module. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the technical solution in the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0058] Figure 1 A schematic flow chart of an embodiment of a method for measuring chromatic aberration of a camera lens module provided in the present application;

[0059] Figure 2 A schematic diagram of a resolution board in the method for measuring chromatic aberration of a camera lens module provided in the present application;

[0060] Figure 3 A schematic flow chart of another embodiment of the method for measuring chromatic aberration of a camera lens module provided in the present application;

[0061] Figure 4 A schematic diagram of the structure of an embodiment of a system for measuring chromatic aberration of a camera lens module provided in the present application;

[0062] Figure 5 A schematic diagram of the structure of an embodiment of a device for measuring chromatic aberration of a camera lens module provided in the present application. DETAILED DESCRIPTION

[0063] The present application provides a method, system and related device for measuring the chromatic aberration of a camera lens module, which are used to achieve quantitative analysis of the chromatic aberration of the lens and improve the chromatic aberration measurement efficiency of the camera lens module.

[0064] It should be noted that the method for measuring the chromatic aberration of a camera lens module provided in this application can be applied to a terminal or a server. For example, the terminal can be a smart phone or a computer, a tablet computer, a smart TV, a smart watch, a portable computer terminal, or a fixed terminal such as a desktop computer. For the convenience of explanation, this application uses a terminal as an example for the execution subject.

[0065] See also Figure 1 , Figure 1 An embodiment of a method for measuring chromatic aberration of a camera lens module provided in the present application includes:

[0066] 101. Arrange the camera lens module, multi-color backlight panel and resolution panel;

[0067] In optical imaging systems, chromatic aberration is caused by light of different wavelengths (different colors) focusing at different positions, a phenomenon that affects the clarity and detail transmission capabilities of the image. In order to simplify the operational process, in addition to the camera lens module being tested, this embodiment only requires the use of a multi-color backlight panel and a resolution panel when quantifying and measuring the chromatic aberration of a camera lens module. The multi-color backlight panel refers to a light source device that can emit a variety of different color light sources, and the color light sources include at least white light, red light, green light, and blue light. The function of the multi-color backlight panel is to provide illumination with light of different wavelengths, which simulate the effects of light of different colors on lens imaging. In the chromatic aberration test, each color light source has different reflection and refraction characteristics, and therefore has different effects on the lens. The resolution panel can specifically use the USAF1951 resolution panel, which is a standard test target used to evaluate the resolution capabilities of a camera or lens. Please refer to Figure 2 , Figure 2 This is a schematic diagram of the USAF1951 resolution plate. The resolution plate is composed of multiple different stripe patterns with different spatial frequencies. It is usually used to test the resolution, contrast and detail retention capabilities of the lens. Each set of stripe patterns corresponds to a specific spatial frequency.

[0068] Specifically, when arranging the camera lens module, the multi-color backlight panel and the resolution panel, the multi-color backlight panel needs to be placed horizontally on a fixed test platform, the resolution panel needs to be evenly illuminated by the multi-color backlight panel, and the camera lens module needs to be placed vertically above the resolution panel. After the fixation is completed, the camera lens module is controlled to move up and down so that the field of view of the camera lens module completely covers the resolution panel, ensuring that the target area of ​​the resolution panel (such as a specific resolution level area) can be fully captured by the camera lens.

[0069] 102. Control the multi-color backlight panel to switch to a white light source, and adjust the exposure setting of the camera lens module to adjust the grayscale of the target area to a preset grayscale;

[0070] White light is a mixture of red, green, blue and other colors, representing the entire visible spectrum. Testing under white light can serve as the basis for the performance of the lens module in a natural environment. Therefore, in the initial stage, by switching the backlight panel to a white light source, ensure that the reference light source for the test is a standard light source that contains all wavelengths.

[0071] In addition, in order to effectively measure color difference, it is also necessary to ensure that the image has a consistent exposure level under different light source conditions. Therefore, it is necessary to adjust the exposure parameters of the camera lens module to ensure that the target area in the image captured by the camera lens module reaches the preset grayscale, thereby ensuring the accuracy and consistency of the test results. The main parameters of exposure include shutter speed, aperture, and ISO value. According to the brightness of the resolution board and the intensity of the backlight board, these exposure parameters are adjusted to make the grayscale value of the target area reach a predetermined level. The preset grayscale value can be determined according to the measurement requirements or application requirements, and is not specifically limited here.

[0072] 103. Shoot a first image of the resolution plate through a camera lens module to obtain a first MTF value of the first image;

[0073] Use the configured camera lens module to capture the first image of the resolution board, and use the image processing algorithm to obtain the first MTF value of the first image. MTF (Modulation Transfer Function) is one of the important indicators for measuring the performance of camera lenses. MTF describes the ability of the lens system to transfer details of different frequencies. The MTF value refers to the value of the modulation transfer function at a specific spatial frequency. When evaluating the quality of an imaging system, the performance of the MTF value at different spatial frequencies is usually considered. Generally speaking, a good imaging system should have a high MTF value over a wide range of spatial frequencies. For a camera lens, the MTF value at a low spatial frequency reflects the lens's ability to image the large outline of an object, while the MTF value at a high spatial frequency reflects the lens's ability to resolve object details (such as texture). Therefore, by capturing an image of the resolution board and calculating the MTF value, the imaging performance of the camera lens module under specific conditions can be objectively evaluated.

[0074] Generally, the calculation of MTF value is based on the line contrast or edge response of the image. First, the edge or stripe area is extracted from the first image obtained by the image processing algorithm. This step usually includes grayscale conversion, edge detection or Fourier transform of the image. Then, by analyzing the contrast attenuation of the image at different frequencies, the first MTF value of the first image at different spatial frequencies is obtained.

[0075] The first MTF value of the first image taken under white light will be used as the benchmark MTF value. This first MTF value reflects the imaging quality of the camera lens module under full-spectrum light sources and provides a unified standard for comparison with subsequent MTF values ​​under red, green, and blue light sources.

[0076] 104. Control the multi-color backlight panel to switch to R, G, and B light sources in sequence, and adjust the exposure setting of the camera lens module to adjust the grayscale of the target area to a preset grayscale;

[0077] When measuring the chromatic aberration of a camera module, the imaging effect may be different under different light sources, especially under different colors of light (such as red, green and blue), factors such as lens focal length, dispersion and optical distortion may lead to different image quality. Different colors of light sources have different intensities and spectral characteristics. In order to quantify the chromatic aberration under different light sources, different colors of light sources need to be used to test the imaging ability of the camera lens. Therefore, the light source of the backlight needs to be switched to red light R, green light G, and blue light B in turn. These are the three common basic colors of light, which can provide sufficient spectral coverage to detect the chromatic aberration of the lens under different light sources.

[0078] In order to ensure that the brightness of the image obtained each time is consistent, the exposure settings need to be adjusted accordingly after each light source switch to ensure that the grayscale value of the target area in the captured image reaches the preset grayscale, thereby ensuring that the brightness and contrast of the image under different light sources remain consistent, so that the difference in MTF values ​​under different light sources can become the basis for evaluating lens chromatic aberration.

[0079] 105. Shoot a second image of the resolution plate through a camera lens module to obtain a second MTF value of the second image;

[0080] For each color of light source, after adjusting the exposure settings, you need to take a second image of the resolution board at this time and obtain the corresponding second MTF value. The first MTF value specifically represents the resolution of the camera lens module under the standard light source (white light) as a reference. The second MTF value represents the resolution of the lens under red, green, and blue light sources respectively.

[0081] 106. Determine the chromatic aberration of the camera lens module according to the first MTF value and the second MTF value.

[0082] When measuring the chromatic aberration of the lens module, different color light sources are used to illuminate the resolution board, and the MTF value obtained reflects the imaging quality of the lens module under different color lights. Chromatic aberration is caused by the dispersion effect of the lens, which causes different wavelengths of light to focus at different positions after passing through the lens, thereby affecting the clarity and resolution of the image. Therefore, by comparing the difference in MTF values ​​under different color light sources, the chromatic aberration of the lens can be quantitatively evaluated. Under the same camera lens module, due to the optical chromatic aberration effect, red, green, and blue light sources may have different focal lengths when passing through the lens, resulting in different MTF values ​​under different color lights. For example, the focus position of red light may be slightly different from that of blue and green light sources, which will affect the ability to transmit high-frequency details and thus affect the MTF value. It can be seen that chromatic aberration will directly affect the clarity of the image under different color light sources, thereby affecting the MTF value. The difference in MTF values ​​under different light sources can reflect the chromatic aberration performance of the lens module. The larger the MTF value, the more accurate the focus of the light of that color and the smaller the chromatic aberration; conversely, the smaller the MTF value, the more blurred the focus of the light of that color and the larger the chromatic aberration.

[0083] Therefore, by shooting the resolution board under the light source of a white light source (including multiple colors) and a single color light source (such as red, green, and blue), the corresponding first MTF value and the second MTF value are obtained. By comparing the first MTF value and the second MTF value, the chromatic aberration of the lens module can be quantitatively evaluated. Specifically, for each light source (red, green, and blue), the difference between its second MTF value and the first MTF value of white light can be calculated respectively, or the average value of the second MTF value can be used to calculate the difference between it and the first MTF value, which is not limited here. The larger the difference, the worse the focusing accuracy under the color light source and the greater the color difference. Conversely, a smaller difference indicates that the imaging quality under the color light source is better and the color difference is smaller.

[0084] In this embodiment, by using a multi-color backlight panel and a resolution panel, and utilizing the different focal lengths of different colors of light focused on the camera sensor after passing through the lens, the MTF values ​​under white, red, green and blue light sources are obtained respectively, and the imaging differences of the camera lens under different color light sources can be clearly quantified. By comparing and analyzing the differences of these MTF values, the chromatic aberration of the lens can be clearly and quantitatively measured, and the chromatic aberration level of the lens can be judged according to the MTF changes under different color lights, so that the measurement of chromatic aberration is more accurate and intuitive, and the chromatic aberration of the lens can be quantitatively analyzed through the changes in the MTF values.

[0085] The entire measurement process only requires the use of a multi-color backlight panel and a resolution panel, without the need for complex instruments such as a reflective light source box and a resolution test card. This simplifies the operation process, makes the operation simpler and more convenient, reduces the measurement difficulty and cost, and greatly improves the color difference measurement efficiency of the camera lens module.

[0086] The following is a detailed description of the method for measuring the chromatic aberration of the camera lens module provided by this application. Figure 3 , Figure 3 Another embodiment of the method for measuring chromatic aberration of a camera lens module provided by the present application includes:

[0087] 301. Arrange the camera lens module, multi-color backlight panel and resolution panel;

[0088] 302. Control the multi-color backlight panel to switch to a white light source, adjust the exposure setting of the camera lens module, and adjust the grayscale of the target area on the resolution panel to a preset grayscale;

[0089] In this embodiment, step 301 - step 302 are similar to step 101 - step 102 of the aforementioned embodiment, and are not described again here.

[0090] In some specific embodiments, the target area corresponds to the white area on the resolution board, and the preset grayscale value can be set to 210 to ensure that the brightness of the target area is bright enough but not overexposed, and to ensure that the overall brightness of the image is within a reasonable range, which can provide good contrast and avoid signal saturation caused by highlight areas, thereby improving the accuracy of MTF analysis.

[0091] 303. Adjust the focal length of the camera lens module to make the camera lens module have clear imaging;

[0092] Before capturing the first image, the focal length of the camera lens module needs to be adjusted to ensure that the camera lens module can accurately focus when capturing the resolution board and obtain a clear first image. To ensure that the focal length is adjusted correctly, the high-contrast pattern on the resolution board can be used as a reference to determine whether the focal length is appropriate by comparing the clarity of the fine lines on the board.

[0093] 304. Capture a first image of the resolution plate through a camera lens module;

[0094] In this embodiment, step 304 is similar to step 103 in the above embodiment and will not be described again here.

[0095] 305. Determine a frequency region according to application requirements, and obtain a first MTF value of the first image in the frequency region, where the frequency region includes a low-frequency region and a high-frequency region;

[0096] In this embodiment, before obtaining the first MTF value, it is necessary to determine the frequency region according to the application requirements, that is, to determine whether to use the MTF analysis of the low-frequency region or the MTF analysis of the high-frequency region. In the MTF analysis, the low-frequency region corresponds to the large-scale structure in the image, usually including relatively smooth and wide brightness changes, such as the outline of large objects, the gradient in the scene, etc. The low-frequency component usually corresponds to the low spatial frequency of the image, and the MTF value of the low-frequency region reflects the ability of the camera lens to process large-scale structures and gradients. The high-frequency region corresponds to the detail information in the image, such as the details of textures, edges and small objects. The high-frequency component usually corresponds to the high spatial frequency of the image. The MTF value of the high-frequency region indicates the performance ability of the lens for these details and tiny structures, and is usually used to evaluate the sharpness and imaging accuracy of the lens. In applications that require fine identification and detection of tiny objects, the lens is required to present high-quality details, and the MTF value of the high-frequency region is more important. However, if the main application scenario is image presentation and visual effects, the lens needs to ensure the clarity and contour presentation of the image, then the MTF value of the low-frequency region may be more important.

[0097] For the first image taken, it is first necessary to perform frequency domain analysis on it. Specifically, the image can be converted from the spatial domain to the frequency domain through Fourier transform, so as to accurately extract low-frequency or high-frequency information, and then obtain the first MTF value of the low-frequency area and / or obtain the first MTF value of the high-frequency area.

[0098] 306. Control the multi-color backlight panel to switch to R, G, and B light sources in sequence, and adjust the exposure setting of the camera lens module to adjust the grayscale of the target area to a preset grayscale;

[0099] In this embodiment, step 306 is similar to step 104 in the above embodiment and will not be described again here.

[0100] 307. Shoot a second image of the resolution plate through a camera lens module to obtain a second MTF value of the second image in a frequency region;

[0101] Similarly, when obtaining the second MTF value, it is also necessary to extract in the corresponding frequency region to obtain the second MTF value of the second image in the low-frequency region and / or obtain the second MTF value in the high-frequency region.

[0102] By determining the frequency region (low-frequency region and high-frequency region) according to the application requirements and obtaining the MTF value of the corresponding region, the performance of the camera lens module can be comprehensively analyzed. The low-frequency region focuses on the large-scale structure of the image, while the high-frequency region focuses on evaluating the lens's ability to present details. This process helps to evaluate the chromatic aberration and resolution performance of the lens from different angles, providing a quantitative basis for optimizing the performance of the lens module.

[0103] 308. Calculate the difference between the first MTF value and the second MTF value, and determine the resolution difference level according to the difference;

[0104] The MTF value reflects the image resolution capability of the lens at different spatial frequencies. By calculating the difference between the first MTF value and the second MTF value and determining the resolution difference level based on the difference value, the size of the chromatic aberration can be effectively quantified, thereby more accurately evaluating the imaging quality of the lens module. For example, if the resolution under white light is 1000 lines / mm and the resolution under red light is 950 lines / mm, the resolution difference is 50 lines / mm, with 100 lines / mm as one level. This difference is converted into a level according to the set rules. Assuming that the resolution difference of each level is 25 lines / mm, the resolution difference level under the red light source is 2 levels.

[0105] If the resolution difference between the first MTF value and the second MTF value is small, it means that the imaging difference of the lens under different color light sources is small, the chromatic aberration is small, and the resolution difference is not significant. If the resolution difference between the first MTF value and the second MTF value is large, it means that the imaging quality of the lens under different color light sources is significantly different, the chromatic aberration is large, and the lens needs to be optimized or corrected.

[0106] In some specific embodiments, considering that different types of lens modules will have different effects on the wavelength differences of RGB light sources, for example, some lenses may be more sensitive to the reflection of red light and less affected by blue light, in this case, a higher weight should be given to the MTF difference of red light. That is, according to the characteristics of the camera lens module, different weights can be given to light sources of different colors according to their degree of influence on the lens module. The terminal specifically performs the following steps:

[0107] The weighting coefficients of the R, G, and B light sources are determined according to the spectral response characteristics of the camera lens module; and the difference between the first MTF value and the second MTF value is calculated according to the weighting coefficients of the R, G, and B light sources.

[0108] Specifically, a corresponding weighting coefficient is set according to the sensitivity of the lens to different colors. The weighting coefficient represents the contribution of different colors of light to the MTF value. The difference between the weighted first MTF value and the second MTF value is calculated based on the weighting coefficient. This allows for more accurate evaluation of chromatic aberration based on the influence of different light sources, thereby reducing misjudgment caused by being overly sensitive or insensitive to a certain color light source.

[0109] 309. Determine whether the color difference of the camera lens module meets the application requirements according to the resolution difference level.

[0110] In actual applications, it is possible to directly determine whether the chromatic aberration of the camera lens module meets the application requirements based on the resolution difference level. The specific judgment criteria can be adjusted according to the actual situation and are not limited here. For example, for scenes with high requirements such as high-resolution imaging and detail detection (such as 0.001mm / pixel defect detection), if the resolution difference level exceeds level 2, the chromatic aberration may have a significant impact on the image quality, and the camera lens module must be adjusted. Therefore, it can be directly set to determine that the chromatic aberration does not meet the application requirements if the resolution difference level exceeds level 1. That is, by calculating and analyzing the resolution difference level and comparing it with the preset tolerance threshold, it is possible to quantitatively determine whether the chromatic aberration of the camera lens module meets the application requirements, thereby quickly evaluating the quality of the lens module.

[0111] The following is a detailed description of the system for measuring the chromatic aberration of the camera lens module provided by this application. Figure 4 , Figure 4 Another embodiment of the system for measuring chromatic aberration of a camera lens module provided by the present application comprises:

[0112] Arrangement unit 401, used for arranging camera lens modules, multi-color backlight panels and resolution panels;

[0113] The first control unit 402 is used to control the multi-color backlight panel to switch to a white light source, and adjust the exposure setting of the camera lens module to adjust the grayscale of the target area to a preset grayscale;

[0114] A first acquisition unit 403 is used to capture a first image of the resolution plate through a camera lens module to acquire a first MTF value of the first image;

[0115] The second control unit 404 is used to control the multi-color backlight panel to switch to R, G, and B light sources in sequence, and adjust the exposure setting of the camera lens module to adjust the grayscale of the target area to a preset grayscale;

[0116] A second acquisition unit 405 is used to capture a second image of the resolution plate through a camera lens module to acquire a second MTF value of the second image;

[0117] The chromatic aberration determining unit 406 is configured to determine the chromatic aberration of the camera lens module according to the first MTF value and the second MTF value.

[0118] Optionally, the color difference determination unit 406 is specifically configured to:

[0119] Calculating a difference between the first MTF value and the second MTF value, and determining a resolution difference level according to the difference;

[0120] Determine whether the chromatic aberration of the camera lens module meets the application requirements based on the resolution difference level.

[0121] Optionally, the color difference determining unit 406 is further configured to:

[0122] Determine the weighting coefficients of R, G, and B light sources according to the spectral response characteristics of the camera lens module;

[0123] The difference between the first MTF value and the second MTF value is calculated according to the R, G, B light source weighting coefficients.

[0124] Optionally, the first acquiring unit 403 is specifically configured to:

[0125] Determine the frequency region according to application requirements, and the frequency region includes a low frequency region and a high frequency region;

[0126] A first MTF value of the first image in the frequency domain is obtained.

[0127] Optionally, the target area corresponds to a white area on the resolution board, and the preset grayscale value is 210.

[0128] Optionally, the arrangement unit 401 is specifically configured to:

[0129] Place the multi-color backlight plate horizontally, use the multi-color backlight plate to evenly illuminate the resolution plate, and place the camera lens module vertically above the resolution plate;

[0130] The camera lens module is controlled to move up and down so that the field of view of the camera lens module completely covers the resolution board.

[0131] Optionally, the first acquiring unit 403 is further configured to:

[0132] Adjust the focal length of the camera lens module to make the camera lens module have clear imaging.

[0133] In this embodiment, the functions of each unit are the same as those described above. Figure 1 or Figure 3 The steps in the method embodiment shown correspond to each other and will not be repeated here.

[0134] This application also provides a device for measuring the chromatic aberration of a camera lens module, see Figure 5 , Figure 5 An embodiment of a device for measuring chromatic aberration of a camera lens module provided in the present application includes:

[0135] Processor 501, memory 502, input and output unit 503, bus 504;

[0136] The processor 501 is connected to the memory 502, the input and output unit 503 and the bus 504;

[0137] The memory 502 stores a program, and the processor 501 calls the program to execute any of the above methods for measuring the chromatic aberration of a camera lens module.

[0138] The present application also relates to a computer-readable storage medium, on which a program is stored. When the program is run on a computer, the computer executes any of the above methods for measuring chromatic aberration of a camera lens module.

[0139] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0140] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0141] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0142] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0143] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the various embodiments of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, read-only memory), random access memory (RAM, random access memory), disk or optical disk, etc. Various media that can store program codes.

Claims

1. A method for measuring chromatic aberration of a camera lens module, characterized in that: The method comprises: Arrange the camera lens module, multi-color backlight board and resolution board; Controlling the multi-color backlight panel to switch to a white light source, and adjusting the exposure setting of the camera lens module to adjust the grayscale of the target area to a preset grayscale; photographing a first image of the resolution plate through the camera lens module, and acquiring a first MTF value of the first image; Controlling the multi-color backlight panel to switch to R, G, and B light sources in sequence, and adjusting the exposure setting of the camera lens module to adjust the grayscale of the target area to the preset grayscale; photographing a second image of the resolution plate through the camera lens module, and acquiring a second MTF value of the second image; The chromatic aberration of the camera lens module is determined according to the first MTF value and the second MTF value.

2. The method according to claim 1, characterized in that The determining the chromatic aberration of the camera lens module according to the first MTF value and the second MTF value includes: Calculating a difference between the first MTF value and the second MTF value, and determining a resolution difference level according to the difference; It is determined whether the chromatic aberration of the camera lens module meets application requirements according to the resolution difference level.

3. The method according to claim 2, characterized in that The calculating the difference between the first MTF value and the second MTF value includes: Determine the R, G, and B light source weighting coefficients according to the spectral response characteristics of the camera lens module; The difference between the first MTF value and the second MTF value is calculated according to the R, G, B light source weighting coefficients.

4. The method according to claim 1, characterized in that: The obtaining a first MTF value of the first image includes: Determine a frequency region according to application requirements, wherein the frequency region includes a low frequency region and a high frequency region; A first MTF value of the first image in the frequency region is obtained.

5. The method according to claim 1, characterized in that: The target area corresponds to the white area on the resolution panel, and the preset grayscale value is 210.

6. The method according to any one of claims 1 to 5, characterized in that The arrangement of the camera lens module, the multi-color backlight panel and the resolution panel includes: Placing a multi-color backlight plate horizontally, using the multi-color backlight plate to evenly illuminate a resolution plate, and vertically placing a camera lens module above the resolution plate; The camera lens module is controlled to move up and down so that the field of view of the camera lens module completely covers the resolution board.

7. The method according to any one of claims 1 to 5, characterized in that Before capturing the first image of the resolution plate through the camera lens module, the method further includes: The focal length of the camera lens module is adjusted to enable the camera lens module to produce a clear image.

8. A system for measuring chromatic aberration of a camera lens module, characterized in that: The system comprises: An arrangement unit, used for arranging a camera lens module, a multi-color backlight panel and a resolution panel; A first control unit, used for controlling the multi-color backlight panel to switch to a white light source, and adjusting the exposure setting of the camera lens module to adjust the grayscale of the target area to a preset grayscale; A first acquisition unit, configured to capture a first image of the resolution plate through the camera lens module, and acquire a first MTF value of the first image; A second control unit is used to control the multi-color backlight panel to switch to R, G, and B light sources in sequence, and adjust the exposure setting of the camera lens module to adjust the grayscale of the target area to the preset grayscale; A second acquisition unit, configured to capture a second image of the resolution plate through the camera lens module, and acquire a second MTF value of the second image; A chromatic aberration determination unit is used to determine the chromatic aberration of the camera lens module according to the first MTF value and the second MTF value.

9. A device for measuring chromatic aberration of a camera lens module, characterized in that: The device comprises: Processor, memory, input-output unit, and bus; The processor is connected to the memory, the input and output unit, and the bus; The memory stores a program, and the processor calls the program to execute the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a program, and when the program is executed on a computer, the method according to any one of claims 1 to 7 is performed.

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