A Mini LED screen backlight brightness unevenness detection system

Abstract

The utility model is suitable for display detection technical field provides a kind of Mini LED screen backlight brightness uneven detection system, including: darkroom box body, inside is equipped with the load platform for placing the Mini LED screen to be measured;Image acquisition module is arranged in darkroom box body and is located the load platform directly above, for the backlight brightness image of the Mini LED screen to be measured;Light source drive module is electrically connected with the Mini LED screen to be measured, for driving the backlight module of the Mini LED screen to be measured and is lit according to preset rule;Image processing module is connected with image acquisition module communication, for carrying out zoned processing to backlight brightness image and calculating the luminance of each zone;Uneven detection module is connected with image processing module communication, for judging whether backlight brightness is uneven according to the luminance difference of each zone, the utility model significantly optimizes the detection ability of the uniformity of Mini LED screen backlight brightness.

Description

Technical Field

[0001] This utility model relates to the field of display testing technology, specifically a Mini LED screen backlight brightness unevenness detection system. Background Technology

[0002] Mini LED (micro-light-emitting diode), as a next-generation display technology, has become a core solution in high-end monitors, televisions, and automotive displays due to its micron-level chip size (typically 50-200μm), high zone density (up to thousands to tens of thousands of zones), high brightness (peak brightness exceeding 1000 nits), and high contrast ratio (typically 1,000,000:1). Its backlight module is formed by an array of Mini LED chips, each of which can be independently controlled to light up. Precise zone dimming enables fine control of local brightness and darkness in the image, significantly improving display quality.

[0003] However, since Mini LED backlight modules are composed of a large number of micro LED chips, uneven backlight brightness is easily caused by differences in chip performance and packaging process deviations during the production process, affecting the display effect. Existing detection methods mostly rely on manual visual inspection or simple optical inspection, which suffers from low detection accuracy, poor efficiency, and inability to quantify and analyze. Therefore, in view of the above situation, there is an urgent need to provide a Mini LED screen backlight brightness unevenness detection system to overcome the shortcomings in current practical applications. Utility Model Content

[0004] The purpose of this invention is to provide a Mini LED screen backlight brightness unevenness detection system, which aims to solve the problems mentioned in the background art.

[0005] This utility model is implemented as follows: a Mini LED screen backlight brightness unevenness detection system, comprising: Darkroom enclosure, wherein the darkroom enclosure is provided with a support platform for placing the Mini LED screen to be tested; An image acquisition module is installed inside the darkroom and located directly above the support platform. The image acquisition module is used to acquire the backlight brightness image of the Mini LED screen under test. A light source driving module is electrically connected to the Mini LED screen under test and is used to drive the backlight module of the Mini LED screen under test to light up according to a preset rule. An image processing module, which is communicatively connected to an image acquisition module, is used to perform partitioning processing on the backlight brightness image and calculate the brightness value of each partition. The unevenness detection module is communicatively connected to the image processing module and is used to determine whether the backlight brightness is uneven based on the difference in brightness values ​​of each zone.

[0006] As a further embodiment of this utility model: the image acquisition module includes: An industrial camera, wherein the lens axis of the industrial camera is perpendicular to the surface of the support platform; A lens filter for filtering ambient stray light, the lens filter being mounted on the front of the lens of an industrial camera; A camera focusing assembly for adjusting the focal length of the industrial camera, wherein the Mini LED screen under test is connected to the industrial camera.

[0007] As a further embodiment of this utility model: the light source driving module includes: A partition driving unit is used to independently drive multiple sub-regions of the Mini LED screen backlight module under test; A brightness adjustment unit, connected to the partition driving unit, is used to adjust the backlight brightness of each sub-region; The timing control unit, connected to the partition drive unit, is used to control the lighting timing of each sub-region.

[0008] As a further embodiment of this utility model: the image processing module includes: An image preprocessing unit is used to perform noise reduction and contrast enhancement processing on the backlight brightness image; The grid division unit is used to divide the preprocessed image into multiple detection partitions according to a preset grid size; The brightness calculation unit is used to calculate the average brightness value and brightness standard deviation of each detection zone.

[0009] As a further embodiment of this utility model: the unevenness detection module includes: The difference calculation unit is used to calculate the brightness difference between adjacent detection zones and the global brightness fluctuation coefficient; A threshold determination unit is used to compare the brightness difference and brightness fluctuation coefficient with a preset threshold. The result output unit is used to output the detection results and position coordinates of uneven brightness based on the comparison results.

[0010] As a further aspect of this utility model, it also includes: A temperature and humidity control module is installed inside the darkroom chamber to adjust the temperature and humidity inside the darkroom chamber to a preset range.

[0011] As a further aspect of this utility model, it also includes: The automatic positioning module includes multiple positioning sensors mounted on the support platform and a displacement adjustment component connected to the positioning sensors, used to automatically correct the placement position of the Mini LED screen under test.

[0012] As a further embodiment of this utility model: the image acquisition module further includes: A multispectral acquisition unit is used to acquire backlight spectral images of the Mini LED screen under test at different wavelengths. The image processing module also includes a spectral analysis unit, used to calculate the color temperature deviation of each zone based on the spectral image.

[0013] As a further aspect of this utility model, it also includes: A data storage module, connected to the unevenness detection module, is used to store the brightness detection data and unevenness analysis results of the Mini LED screen under test; The report generation module, connected to the data storage module, is used to generate a brightness unevenness detection report.

[0014] As a further embodiment of this utility model: the inner wall of the darkroom box is provided with a light-absorbing layer, and the surface of the light-absorbing layer has a honeycomb structure, which is used to absorb the backlight reflected light of the Mini LED screen under test.

[0015] Compared with the prior art, the beneficial effects of this utility model are as follows: This invention constructs an interference-free detection environment by using a darkroom enclosure with a honeycomb light-absorbing layer, effectively avoiding the influence of external light reflection and stray light on the detection results. Through the coordinated operation of the image acquisition module and the light source driving module, it can achieve global detection in a static, fully lit state, as well as precise local detection during dynamic, zoned lighting, adapting to different backlight operating modes. Through the zoned processing and spectral analysis functions of the image processing module, it can not only accurately analyze differences in brightness distribution but also identify color-shifted brightness unevenness caused by spectral characteristic deviations, expanding the detection dimensions. Combined with automatic positioning adjustment and full-process automated control, it reduces manual intervention, improves detection consistency and efficiency, and supports flexible adaptation to Mini LED screens of different sizes and specifications. It provides comprehensive and reliable technical support for quality screening, performance evaluation, and reliability verification during the production process, significantly optimizing the detection capability of Mini LED screen backlight brightness uniformity. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a system architecture diagram of the present invention.

[0018] Figure 2 This is an architectural diagram of the light source driving module in this utility model.

[0019] Figure 3 This is an architectural diagram of the image processing module in this utility model.

[0020] Figure 4 This is a diagram illustrating the architecture of the unevenness detection module in this invention. Detailed Implementation

[0021] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0022] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0023] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0024] The specific implementation of this utility model will be described in detail below with reference to specific embodiments.

[0025] Please see Figures 1-4 This utility model provides a Mini LED screen backlight brightness unevenness detection system, which includes: Darkroom enclosure 100, the darkroom enclosure 100 is provided with a support platform 110 for placing the Mini LED screen to be tested; An image acquisition module 200 is installed inside the darkroom enclosure 100 and located directly above the support platform 110. The image acquisition module 200 is used to acquire the backlight brightness image of the Mini LED screen under test. The image acquisition module 200 includes: An industrial camera 210, wherein the lens axis of the industrial camera 210 is perpendicular to the surface of the support platform 110; A lens filter 220 for filtering ambient stray light is mounted on the front end of the lens of an industrial camera 210. A camera focusing assembly 230 for adjusting the focal length of the industrial camera 210, wherein the Mini LED screen to be tested is connected to the industrial camera 210; The multispectral acquisition unit 240 is used to acquire backlight spectrum images of the Mini LED screen under test at different wavelengths. A light source driving module 300 is electrically connected to the Mini LED screen under test and is used to drive the backlight module of the Mini LED screen under test to light up according to a preset rule. The light source driving module 300 includes: The partition driving unit 310 is used to independently drive multiple sub-regions of the backlight module of the Mini LED screen under test; The brightness adjustment unit 320 is connected to the partition driving unit 310 and is used to adjust the backlight brightness of each sub-region. The timing control unit 330 is connected to the partition driving unit 310 and is used to control the lighting timing of each sub-region. Image processing module 400, which is communicatively connected to image acquisition module 200, is used to perform partitioning processing on the backlight brightness image and calculate the brightness value of each partition; The image processing module 400 includes: Image preprocessing unit 410 is used to perform noise reduction and contrast enhancement processing on the backlight brightness image; The grid division unit 420 is used to divide the preprocessed image into multiple detection partitions according to a preset grid size; The brightness calculation unit 430 is used to calculate the average brightness value and brightness standard deviation of each detection zone; The spectral analysis unit 440 is used to calculate the color temperature deviation of each zone based on the spectral image; An unevenness detection module 500, communicatively connected to the image processing module 400, is used to determine whether the backlight brightness is uneven based on the difference in brightness values ​​of each zone. The unevenness detection module 500 includes: The difference calculation unit 510 is used to calculate the brightness difference between adjacent detection zones and the global brightness fluctuation coefficient; The threshold judgment unit 520 is used to compare the brightness difference and brightness fluctuation coefficient with a preset threshold. The result output unit 530 is used to output the detection results and position coordinates of uneven brightness based on the comparison results.

[0026] In this embodiment of the invention, the darkroom enclosure 100 is made of light-shielding material. The light source driving module 300 is connected to the Mini LED screen under test via an FPC interface. The partition driving unit 310 can independently control 1024 sub-regions of the backlight module. The brightness adjustment unit 320 supports continuous adjustment of brightness from 0 to 1000 nits. The timing control unit 330 can set the lighting frequency from 1 to 100 Hz to achieve dynamic backlight detection. The image preprocessing unit 410 first uses an adaptive Gaussian filtering algorithm to remove high-frequency noise caused by tiny bright spots in the Mini LED chip from the original backlight image acquired by the image acquisition module 200, while preserving brightness gradient details. Then, it uses the CLAHE limited contrast adaptive histogram equalization algorithm to enhance local contrast, solve the problem of loss of details in dark areas caused by backlight edge attenuation, and make brightness differences in low-brightness areas easier to identify. Based on the intrinsic parameter matrix of the industrial camera 210, it corrects the lens optical distortion to ensure that the spatial position of each pixel in the image corresponds one-to-one with the physical position of the Mini LED screen under test.

[0027] The grid division unit 420 adopts the "physical coordinate mapping method": based on the backlight module zoning design of the Mini LED screen under test, the preprocessed image is divided into detection grids that perfectly match the physical sub-regions, with each grid corresponding to one or more Mini LED chip groups; the grid ratio is automatically scaled based on the actual screen size information fed back by the automatic positioning module 700 to adapt to Mini LED screens of different specifications.

[0028] The difference calculation unit 510 calculates the brightness difference between adjacent detection grids, focusing on identifying abrupt brightness differences between adjacent sub-regions within the same area, such as local dark spots caused by chip failure.

[0029] In one embodiment of this utility model, it further includes: A temperature and humidity control module 600 is installed inside the darkroom enclosure 100 to adjust the temperature and humidity inside the darkroom enclosure 100 to a preset range.

[0030] In this embodiment, the temperature and humidity control module 600 controls the internal temperature of the dark room at 25±2℃ and the humidity at 50±5%RH.

[0031] In one embodiment of this utility model, it further includes: The automatic positioning module 700 includes multiple positioning sensors 710 disposed on the support platform 110 and a displacement adjustment component 720 connected to the positioning sensors 710, for automatically correcting the placement position of the Mini LED screen under test.

[0032] In this embodiment, the automatic positioning module 700, in conjunction with the replaceable fixture, enables fully automatic calibration after the screen is placed. The testing process requires no manual intervention, and the testing time for a single screen is reduced from 3-5 minutes in the prior art to less than 30 seconds, meeting the cycle time requirements of mass production lines.

[0033] In one embodiment of this utility model, it further includes: The data storage module 800 is connected to the unevenness detection module 500 and is used to store the brightness detection data and unevenness analysis results of the Mini LED screen under test. The report generation module 900 is connected to the data storage module 800 and is used to generate a brightness unevenness detection report.

[0034] In this embodiment, the data storage module 800 and the report generation module 900 complete data storage and report generation.

[0035] In one embodiment of this utility model, the inner wall of the darkroom box 100 is provided with a light-absorbing layer 120, the surface of which has a honeycomb structure to absorb the backlight reflected light of the Mini LED screen to be tested.

[0036] In this embodiment, the light-absorbing layer 120 on the inner wall has a black honeycomb structure, which can effectively absorb reflected light and avoid interference from ambient light.

[0037] In summary, the working principle of this utility model is as follows: The Mini LED screen to be tested is placed on the support platform 110 inside the darkroom chamber 100. The positioning sensor 710 of the automatic positioning module 700 identifies the position of the screen, and the displacement adjustment component 720 corrects the screen to the detection reference position to ensure accurate detection position. The temperature and humidity control module 600 is activated, adjusting the internal temperature and humidity of the darkroom chamber 100 to a preset range suitable for detection. At the same time, the light-absorbing layer 120 on the inner wall absorbs reflected light and eliminates environmental interference. The light source driving module 300 drives the backlight module of the Mini LED screen under test to light up according to preset modes such as static full brightness and partitioned dynamic lighting through the partition driving unit 310, brightness adjustment unit 320 and timing control unit 330. The industrial camera 210, lens filter 220 and multispectral acquisition unit 240 of the image acquisition module 200 synchronously acquire backlight brightness image and spectrum image, and the camera focusing component 230 ensures clear imaging. The acquired image is transmitted to the image processing module 400. The image preprocessing unit 410 performs noise reduction and contrast enhancement. The grid division unit 420 divides the image into detection zones. The brightness calculation unit 430 calculates the brightness parameters of each zone. The spectral analysis unit 440 analyzes the spectral image to obtain parameters such as color temperature. The difference calculation unit 510 of the unevenness detection module 500 analyzes the brightness difference of each zone, the threshold judgment unit 520 compares with the preset threshold to determine whether there is unevenness, the result output unit 530 presents the uneven area and the detection result, the data storage module 800 saves the detection data, and the report generation module 900 generates the detection report.

[0038] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A Mini LED screen backlight brightness unevenness detection system, characterized in that, include: A darkroom enclosure (100) is provided inside which a support platform (110) is provided for placing the Mini LED screen under test; an image acquisition module (200) is set inside the darkroom enclosure (100) and located directly above the support platform (110), the image acquisition module (200) is used to acquire the backlight brightness image of the Mini LED screen under test; a light source driving module (300) is electrically connected to the Mini LED screen under test, and is used to drive the backlight module of the Mini LED screen under test to light up according to a preset rule; an image processing module (400) is communicatively connected to the image acquisition module (200), and is used to perform partition processing on the backlight brightness image and calculate the brightness value of each partition; an unevenness detection module (500) is communicatively connected to the image processing module (400), and is used to determine whether the backlight brightness is uneven based on the difference in brightness value of each partition.

2. The Mini LED screen backlight brightness unevenness detection system according to claim 1, characterized in that, The image acquisition module (200) includes: an industrial camera (210) with its lens axis perpendicular to the surface of the support platform (110); a lens filter (220) for filtering ambient stray light, the lens filter (220) being mounted on the front end of the lens of the industrial camera (210); and a camera focusing assembly (230) for adjusting the focal length of the industrial camera (210), wherein the Mini LED screen to be tested is connected to the industrial camera (210).

3. The Mini LED screen backlight brightness unevenness detection system according to claim 1, characterized in that, The light source driving module (300) includes: a partition driving unit (310) for independently driving multiple sub-regions of the backlight module of the Mini LED screen under test; a brightness adjustment unit (320) connected to the partition driving unit (310) for adjusting the backlight brightness of each sub-region; and a timing control unit (330) connected to the partition driving unit (310) for controlling the lighting timing of each sub-region.

4. The Mini LED screen backlight brightness unevenness detection system according to claim 1, characterized in that, The image processing module (400) includes: an image preprocessing unit (410) for performing noise reduction and contrast enhancement processing on the backlight brightness image; a grid division unit (420) for dividing the preprocessed image into multiple detection zones according to a preset grid size; and a brightness calculation unit (430) for calculating the average brightness value and brightness standard deviation of each detection zone.

5. The Mini LED screen backlight brightness unevenness detection system according to claim 1, characterized in that, The unevenness detection module (500) includes: a difference calculation unit (510) for calculating the brightness difference between adjacent detection zones and the global brightness fluctuation coefficient; a threshold judgment unit (520) for comparing the brightness difference and brightness fluctuation coefficient with a preset threshold; and a result output unit (530) for outputting the detection result and location coordinates of the unevenness based on the comparison result.

6. The Mini LED screen backlight brightness unevenness detection system according to claim 1, characterized in that, Also includes: A temperature and humidity control module (600) is installed inside the darkroom enclosure (100) to adjust the temperature and humidity inside the darkroom enclosure (100) to a preset range.

7. The Mini LED screen backlight brightness unevenness detection system according to claim 1, characterized in that, Also includes: The automatic positioning module (700) includes multiple positioning sensors (710) disposed on the support platform (110) and a displacement adjustment component (720) connected to the positioning sensors (710), for automatically correcting the placement position of the Mini LED screen under test.

8. The Mini LED screen backlight brightness unevenness detection system according to claim 1, characterized in that, The image acquisition module (200) further includes a multispectral acquisition unit (240) for acquiring backlight spectral images of the Mini LED screen under test at different wavelengths; the image processing module (400) further includes a spectral analysis unit (440) for calculating the color temperature deviation of each zone based on the spectral images.

9. The Mini LED screen backlight brightness unevenness detection system according to claim 1, characterized in that, Also includes: The data storage module (800), connected to the unevenness detection module (500), is used to store the brightness detection data and unevenness analysis results of the Mini LED screen under test; the report generation module (900), connected to the data storage module (800), is used to generate a brightness unevenness detection report.

10. The Mini LED screen backlight brightness unevenness detection system according to claim 1, characterized in that, The inner wall of the darkroom enclosure (100) is provided with a light-absorbing layer (120), the surface of which has a honeycomb structure to absorb the backlight reflected light of the Mini LED screen to be tested.

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