Method and device for measuring brightness uniformity of display panel

Abstract

The invention provides a display panel brightness uniformity measurement method and device, and the method comprises the steps: obtaining a target image, collected by a camera, of a display panel, and enabling the display panel to display a specified gray scale image; obtaining a display panel region of interest in the target image; equally dividing the region of interest of the display panel into N blocks according to the number N of the required test points; determining the average brightness of each block according to the brightness data of all the pixels in each block; and according to the average brightness of all the blocks, determining that the brightness of the display panel is consistent with the LRU data.

Description

Technical Field

[0001] Embodiments of the present invention relate to the field of display technologies, and in particular, to a method and a device for measuring the brightness uniformity of a display panel. Background Art

[0002] Brightness uniformity (Launch Range Uniformity, LRU) is an important factor affecting the display effect of a display panel. Currently, it is necessary to introduce LRU to test and evaluate the performance of the display panel to help confirm whether there are weak brightness drifts and non-uniform phenomena that are difficult for the human eye to identify in the display panel.

[0003] Currently, whether in the laboratory or on the production line, the method for analyzing LRU data is to use color analyzers such as CA310 / CA410 to respectively measure the brightness data of multiple specific test points within the screen of the display panel, and calculate the LRU data based on these brightness data. Among them, the acquisition of the brightness data of each test point requires a certain response time. When the screen of the display panel is large and the number of test points is large, the time for collecting the brightness data plus the time for data recording and analysis is long, making it difficult to meet the measurement requirements. Summary of the Invention

[0004] Embodiments of the present invention provide a method and a device for measuring the brightness uniformity of a display panel, which are used to solve the problem that the existing method for measuring the brightness uniformity of a display panel takes a long time and is difficult to meet the measurement requirements.

[0005] To solve the above technical problems, the present invention is implemented as follows:

[0006] In a first aspect, embodiments of the present invention provide a method for measuring the brightness uniformity of a display panel, including:

[0007] Obtaining a target image of the display panel collected by a camera, where the display panel displays a specified gray-scale picture;

[0008] Obtaining a region of interest of the display panel in the target image;

[0009] Dividing the region of interest of the display panel into N blocks evenly according to the required number of test points N;

[0010] Determining the average brightness of each block according to the brightness data of all pixels within each block;

[0011] Determining the brightness uniformity LRU data of the display panel according to the average brightness of all the blocks.

[0012] Optionally, the obtaining the region of interest of the display panel in the target image includes:

[0013] Use an image segmentation algorithm to segment the target image into a region of interest of the display panel and a background region;

[0014] Locate and extract the region of interest of the display panel in the target image.

[0015] Optionally, the obtaining of the target image of the display panel collected by the camera includes: loading the target image of the display panel collected by the camera into the user interface of the LRU measurement and calculation system;

[0016] The method further includes: obtaining parameter information set through the user interface, where the parameter information includes the number of test points.

[0017] Optionally, the obtaining of the region of interest of the display panel in the target image includes:

[0018] Perform image preprocessing on the target image using the De-Mura algorithm to obtain an image of the region of interest of the display panel in the target image.

[0019] Optionally, after performing image preprocessing on the target image using the De-Mura algorithm to obtain the region of interest of the display panel in the target image, it further includes:

[0020] Load the image of the region of interest of the display panel into the user interface of the LRU measurement and calculation system;

[0021] The method further includes: obtaining parameter information set through the user interface, where the parameter information includes the number of test points.

[0022] Optionally, the determining of the LRU data with uniform brightness of the display panel according to the average brightness of all the blocks includes:

[0023] Obtain the maximum value and the minimum value among the average brightnesses of all the blocks;

[0024] Calculate the result of dividing the minimum value by the maximum value as the LRU data of the display panel.

[0025] In a second aspect, an embodiment of the present invention provides a device for measuring the brightness uniformity of a display panel, including:

[0026] An image acquisition module, configured to acquire a target image of a display panel collected by a camera, where the display panel displays a specified gray-scale picture;

[0027] A region-of-interest acquisition module, configured to acquire a region of interest of the display panel in the target image;

[0028] A partitioning module, configured to evenly divide the region of interest of the display panel into N blocks according to the required number of test points N;

[0029] An average brightness determination module, configured to determine the average brightness of each block according to the brightness data of all pixels within each block;

[0030] An LRU determination module, configured to determine LRU data with uniform brightness of the display panel according to the average brightness of all the blocks.

[0031] In a third aspect, an embodiment of the present invention provides an electronic device, including: a processor, a memory, and a program stored on the memory and executable on the processor, where when the program is executed by the processor, the steps of the display panel brightness uniformity measurement method described in the first aspect above are implemented.

[0032] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the display panel brightness uniformity measurement method described in the first aspect above are implemented.

[0033] In a fifth aspect, an embodiment of the present invention provides a computer program product, including computer instructions, where when the computer instructions are executed by a processor, the steps of the display panel brightness uniformity measurement method described in the first aspect above are implemented.

[0034] In the embodiment of the present invention, a target image of a specified gray-scale picture displayed on the display panel is collected by a camera, and image processing is performed on the target image according to the number of test points to obtain brightness information corresponding to each test point, and the LRU data of the display panel is calculated based on the obtained brightness information. There is no need to collect the brightness data of each test point one by one, which can greatly reduce the time for collecting, recording, and analyzing the brightness data, and quickly obtain the LRU data of the display panel. In addition, different specified gray scales and different numbers of test points can be dealt with, and the measurement cost will not increase. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] By reading the detailed description of the preferred embodiments below, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of showing the preferred embodiments and are not considered to be a limitation of the present invention. Moreover, throughout the drawings, the same reference numerals are used to represent the same components. In the drawings:

[0036] Figure 1 is a schematic flowchart of the display panel brightness uniformity measurement method according to an embodiment of the present invention;

[0037] Figure 2 is a schematic diagram of the scenario where a camera collects a target image of the display panel according to an embodiment of the present invention;

[0038] Figure 3 Schematic flowchart of the method for measuring the display panel brightness uniformity in two modes according to an embodiment of the present invention;

[0039] Figure 4 Schematic diagram of the user interface of the LRU measurement and calculation system according to an embodiment of the present invention;

[0040] Figure 5 Schematic diagram of the method for measuring the display panel brightness uniformity in the prior art I;

[0041] Figure 6 Schematic structural diagram of the display panel brightness uniformity measurement device according to an embodiment of the present invention;

[0042] Figure 7 Schematic structural diagram of the electronic device according to an embodiment of the present invention. Detailed implementation manners

[0043] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0044] Please refer to Figure 1 , an embodiment of the present invention provides a method for measuring the display panel brightness uniformity, including:

[0045] Step S1: Obtain a target image of the display panel collected by a camera, where the display panel displays a specified gray-scale picture;

[0046] Please refer to Figure 2 , the camera can be fixed at a preset camera position, and the display panel to be measured is placed within the field of view of the camera, with the screen of the display panel facing the camera, so that a complete image of the screen of the display panel can be collected.

[0047] The camera used in the embodiment of the present invention can be an ordinary charge-coupled device (CCD) area array camera.

[0048] In the embodiment of the present invention, the format of the target image can be a BMP image. Of course, it can also be other types of images, such as JPG images, etc., which is related to the settings of the camera.

[0049] In the embodiment of the present invention, the image of the display panel can be collected in a darkroom environment, which is convenient for separating the background area in the subsequent image segmentation process.

[0050] In the embodiments of the present invention, a specified gray-scale image displayed by the display panel can be determined according to specific measurement requirements. For example, if an image with L16 gray scale needs to be measured, the display panel is controlled to display an L16 gray-scale image. If an image with L32 gray scale needs to be tested, the display panel is controlled to display an L32 gray-scale image.

[0051] Step S2: Obtain the region of interest (ROI) of the display panel in the target image;

[0052] In the embodiments of the present invention, the region of interest (ROI) is the screen area of the display panel.

[0053] Step S3: Divide the region of interest of the display panel into N blocks evenly according to the required number of test points N;

[0054] In the embodiments of the present invention, the number of test points can be 9, 15, 135, etc., and the present invention does not make any limitations.

[0055] Step S4: Determine the average brightness of each block according to the brightness data of all pixels in each block;

[0056] In the embodiments of the present invention, the brightness data of the pixels can be relative brightness data, that is, the brightness data relative to the camera exposure.

[0057] The average brightness of each block is equivalent to the brightness data of the measurement point corresponding to each block.

[0058] Step S5: Determine the luminance uniformity (LRU) data of the display panel according to the average brightness of all the blocks.

[0059] In the embodiments of the present invention, the target image of the specified gray-scale image displayed by the display panel is collected by a camera, and the target image is processed according to the number of test points to obtain the brightness information corresponding to each test point, and the LRU data of the display panel is calculated based on the obtained brightness information. There is no need to collect the brightness data of each test point one by one, which can greatly reduce the time for collecting, recording, and analyzing the brightness data, and quickly obtain the LRU data of the display panel. In addition, different specified gray scales and different numbers of test points can be handled, and the measurement cost will not increase.

[0060] In the embodiments of the present invention, two modes are supported for calculating the luminance uniformity of the display panel, which will be described in detail below.

[0061] The first mode:

[0062] In some embodiments, optionally, the obtaining the region of interest of the display panel in the target image includes:

[0063] Step S21: Segment the target image into the region of interest of the display panel and the background region using an image segmentation algorithm;

[0064] In an embodiment of the present invention, an image segmentation algorithm such as a thresholding algorithm can be used to segment the target image into the region of interest of the display panel and the background region.

[0065] Step S22: Locate and extract the region of interest of the display panel;

[0066] In an embodiment of the present invention, a Region Block (region block) location algorithm can be used to extract the region of interest of the display panel. The region block location algorithm is usually used in scenarios such as image processing to identify and locate specific regions.

[0067] In an embodiment of the present invention, in order to facilitate the user to measure the LRU data of the display panel, the LRU data of the display panel can be measured in the way of a visualization system.

[0068] In some embodiments, optionally, obtaining the target image of the display panel collected by the camera includes: loading the target image of the display panel collected by the camera into the user interface of the LRU measurement and calculation system; that is, loading the collected original image into the user interface of the LRU measurement and calculation system.

[0069] The method further includes: obtaining parameter information set through the user interface, where the parameter information includes the number of test points.

[0070] Optionally, the parameter information may further include image resolution, etc.

[0071] Among them, the following steps are automatically completed by the LRU measurement and calculation system:

[0072] Obtain the region of interest of the display panel in the target image;

[0073] According to the required number of test points N, divide the region of interest of the display panel into N sub-blocks evenly;

[0074] Determine the average brightness of each sub-block according to the brightness data of all pixels in each sub-block;

[0075] Determine the LRU data with uniform brightness of the display panel according to the average brightness of all sub-blocks.

[0076] Please refer to Figure 3, in the first mode, the original data (RAW DATA), i.e., the target image collected by the camera, is obtained by the LRU measurement and calculation system, and the target image is thresholded to obtain the region of interest and the background region of the display panel. Then, the Region Block positioning algorithm is used to locate and extract the region of interest of the display panel.

[0077] Please refer to Figure 4 , Figure 4 FIG. is a schematic diagram of the user interface of the LRU measurement and calculation system according to an embodiment of the present invention. It can be seen from the user interface that the user can click "File Load" to load the target image collected by the camera into the LRU measurement and calculation system, and then set parameter information through the user interface, such as setting the number of test points and image resolution, etc. Finally, when the user clicks "(LRU) Calculate", the following steps can be directly executed: obtaining the region of interest of the display panel in the target image; dividing the region of interest of the display panel into N blocks evenly according to the required number of test points N; determining the average brightness of each block according to the brightness data of all pixels in each block; determining the LRU data with uniform brightness of the display panel according to the average brightness of all blocks.

[0078] Second mode:

[0079] In some other embodiments, optionally, the obtaining the region of interest of the display panel in the target image includes:

[0080] Step S21': performing image pre-processing (Pre-Processing) on the target image by using the De-Mura algorithm to obtain the image of the region of interest of the display panel in the target image.

[0081] That is to say, the method executed by steps S21 - S22 above is replaced by the De-Mura algorithm instead of the LRU measurement and calculation system.

[0082] In the embodiment of the present invention, the image of the region of interest of the display panel obtained by performing image pre-processing on the target image by using the De-Mura algorithm can be an image in BMP format or an image in CSV format, and the present invention does not make any restrictions.

[0083] In the embodiment of the present invention, optionally, after performing image pre-processing on the target image by using the De-Mura algorithm to obtain the image of the region of interest of the display panel, the following is further included: loading the image corresponding to the region of interest of the display panel into the user interface of the LRU measurement and calculation system; that is, loading the (De-Mura algorithm) pre-processed image into the user interface of the LRU measurement and calculation system.

[0084] The method further includes: obtaining parameter information set through the user interface, where the parameter information includes the number of test points.

[0085] Optionally, the parameter information may further include image resolution, setting information on whether to use the original image or the preprocessed image, etc.

[0086] Among them, the following steps are automatically completed by the LRU measurement and calculation system:

[0087] Dividing the region of interest of the display panel into N blocks evenly according to the required number of test points N;

[0088] Determining the average brightness of each block according to the brightness data of all pixels within each block;

[0089] Determining the LRU data with uniform brightness of the display panel according to the average brightness of all the blocks.

[0090] Please refer to Figure 3 , in the second mode, the original data (RAW DATA) is obtained by the De-Mura algorithm (DMR), that is, the target image collected by the camera, and the target image is processed to obtain the preprocessed Data of DMR, that is, the image of the region of interest of the display panel in the target image and the brightness data of all pixels in the region of interest of the display panel.

[0091] It can be seen that the subsequent steps of the first mode and the second mode are the same, and are both executed by the LRU measurement and calculation system.

[0092] In some embodiments, optionally, the determining the LRU data with uniform brightness of the display panel according to the average brightness of all the blocks includes:

[0093] Step S51: Obtaining the maximum value and the minimum value among the average brightnesses of all the blocks;

[0094] Step S52: Calculating the result of dividing the minimum value by the maximum value as the LRU data of the display panel.

[0095] Of course, in some other embodiments of the present invention, it is not excluded to calculate the LRU data by other calculation methods, such as adding the average brightnesses of all blocks and then taking the average, etc.

[0096] The display panel in the embodiments of the present invention may be an OLED display panel or other types of display panels.

[0097] The size of the display panel in the embodiments of the present invention is not limited, and the brightness uniformity measurement can be performed on display panels of any size.

[0098] The display panel brightness uniformity measurement method in the embodiments of the present invention is not limited to laboratory operations and can also be used for production line analysis.

[0099] The measurement accuracy of the display panel brightness uniformity measurement method of the present invention is illustrated by experimental results below.

[0100] Prior art one: Conventional tests all use color analyzers CA310 / CA410 to measure the brightness uniformity of display panels, as Figure 5 shown. Limited by the geometric size of the color analyzer and the size of the display panel, fine measurement at multiple test points cannot be achieved. Under most conditions, only LRU-9 (9 test points) or LRU-15 (15 test points) measurements can be realized, and the characterization accuracy of the display panel brightness uniformity measurement results is poor.

[0101] Prior art two: Use large-scale dedicated optical chamber equipment for measurement, which can achieve accurate fine multi-test point measurements such as LRU-135. However, the equipment purchase price exceeds 1 million, the cost is expensive, and post-maintenance is required.

[0102] The solution of the present invention: It is realized through a camera + image analysis algorithm, and the hardware cost is only in the construction and development of the camera hardware platform, and the cost is relatively low. Therefore, the advantages of prior art one / two can be taken into account. Under the premise of ensuring multi-test points and high-accuracy measurement characterization of test requirements, the cost is low and it is easier to implement.

[0103] The comparison results of the LRU test accuracy between prior art one / two and the present invention can be referred to Table 1:

[0104] Table 1 Comparison of measurement accuracies of different measurement schemes

[0105]

[0106] It can be seen from Table 1 that the measurement accuracy of the display panel brightness uniformity measurement method of the present invention is comparable to that of prior art two, and the implementation cost is much lower than that of prior art two.

[0107] For example, when analyzing the compensation degree of Demura of a display panel, at least 5 to 10 display panels need to be measured for LRU to assist in judging whether there is uncompensated or overcompensated phenomenon. When the method of the present invention is used, compared with prior art one, the workload of 5 days can be compressed to be completed within 2 to 3 days, greatly reducing the time cost.

[0108] Please refer to Figure 6 , and the embodiments of the present invention further provide a display panel brightness uniformity measurement device 10, including:

[0109] An image acquisition module 11 is configured to acquire a target image of a display panel collected by a camera, where the display panel displays a specified grayscale screen;

[0110] A region of interest acquisition module 12 is configured to acquire a region of interest of the display panel in the target image;

[0111] A partitioning module 13 is configured to evenly divide the region of interest of the display panel into N blocks according to the required number of test points N;

[0112] An average brightness determination module 14 is configured to determine the average brightness of each block according to the brightness data of all pixels within each block;

[0113] An LRU determination module 15 is configured to determine LRU data indicating that the brightness of the display panel is uniform according to the average brightness of all the blocks.

[0114] In an embodiment of the present invention, a target image of a specified grayscale screen displayed by a display panel is collected by a camera, and image processing is performed on the target image according to the number of test points to obtain brightness information corresponding to each test point, and LRU data of the display panel is calculated based on the obtained brightness information. It is not necessary to collect the brightness data of each test point one by one, which can greatly reduce the time for collecting, recording, and analyzing the brightness data, and quickly obtain the LRU data of the display panel. In addition, different specified grayscales and different numbers of test points can be handled, and the measurement cost will not increase.

[0115] Optionally, the region of interest acquisition module 12 is configured to segment the target image into a region of interest of the display panel and a background region by using an image segmentation algorithm; locate and extract the region of interest of the display panel.

[0116] Optionally, the image acquisition module 11 is configured to load the target image of the display panel collected by the camera into a user interface of an LRU measurement and calculation system;

[0117] The display panel brightness uniformity measurement device 10 further includes:

[0118] A parameter setting module is configured to acquire parameter information set through the user interface, where the parameter information includes the number of test points.

[0119] Optionally, the region of interest acquisition module 12 is configured to perform image preprocessing on the target image by using a De-Mura algorithm to obtain an image of the region of interest of the display panel in the target image.

[0120] Optionally, the display panel brightness uniformity measurement device 10 further includes:

[0121] A loading module for loading the image of the region of interest of the display panel into the user interface of the LRU measurement calculation system;

[0122] A parameter setting module for obtaining parameter information set through the user interface, where the parameter information includes the number of test points.

[0123] Optionally, the LRU determination module 15 is configured to obtain the maximum value and the minimum value among the average brightnesses of all the blocks; calculate the result of dividing the minimum value by the maximum value as the LRU data of the display panel.

[0124] Please refer to Figure 7 , an embodiment of the present invention further provides an electronic device 20, including a processor 21, a memory 22, and a computer program stored on the memory 22 and executable on the processor 21. When the computer program is executed by the processor 21, it implements each process of the embodiment of the above display panel brightness uniformity measurement method and can achieve the same technical effect. To avoid repetition, it will not be elaborated here.

[0125] An embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it implements each process of the embodiment of the above display panel brightness uniformity measurement method and can achieve the same technical effect. To avoid repetition, it will not be elaborated here. Among them, the computer-readable storage medium is, for example, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disc, etc.

[0126] An embodiment of the present application further provides a computer program product, including computer instructions, which when executed by a processor implement each process of the above Figure 1 shown method embodiment and can achieve the same technical effect. To avoid repetition, it will not be elaborated here.

[0127] It should be noted that in this article, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or further includes elements inherent to such process, method, article or device. Without more limitations, an element defined by the statement "including one..." does not exclude the existence of another identical element in the process, method, article or device including the element.

[0128] Through the description of the above embodiments, those skilled in the art can clearly understand that the above-described embodiment methods can be implemented by means of software plus a necessary general hardware platform. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation. Based on such an understanding, the technical solution of the present invention, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions for causing a terminal (which can be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in various embodiments of the present invention.

[0129] The embodiments of the present invention have been described above in conjunction with the accompanying drawings. However, the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present invention, those of ordinary skill in the art can also make many forms without departing from the purpose of the present invention and the scope protected by the claims, and all of them belong to the protection scope of the present invention.

Claims

1. A method for measuring brightness uniformity of a display panel, characterized in that: include: Acquire a target image of a display panel captured by a camera, wherein the display panel displays a specified grayscale image; Acquire a display panel region of interest in the target image; According to the required number of test points N, the region of interest of the display panel is equally divided into N blocks; Determine the average brightness of each of the blocks according to the brightness data of all pixels in each of the blocks; According to the average brightness of all the blocks, it is determined that the brightness of the display panel is consistent with the LRU data.

2. The method according to claim 1, characterized in that: The acquiring the display panel region of interest in the target image comprises: Using an image segmentation algorithm to segment the target image into a display panel region of interest and a background region; The display panel region of interest is located and extracted.

3. The method according to claim 2, characterized in that The acquiring the target image of the display panel acquired by the camera comprises: loading the target image of the display panel acquired by the camera into a user interface of the LRU measurement and calculation system; The method further includes: acquiring parameter information set through the user interface, the parameter information including the number of test points.

4. The method according to claim 1, characterized in that: The acquiring the display panel region of interest in the target image comprises: The target image is preprocessed by using a De-Mura algorithm to obtain an image of the region of interest of the display panel in the target image.

5. The method according to claim 4, characterized in that The De-Mura algorithm is used to perform image preprocessing on the target image to obtain the display panel area of ​​interest in the target image, and then further includes: Loading the image of the region of interest of the display panel into the user interface of the LRU measurement and calculation system; The method further includes: acquiring parameter information set through the user interface, the parameter information including the number of test points.

6. The method according to claim 1, characterized in that The step of determining, based on the average brightness of all the blocks, that the brightness of the display panel is consistent with the LRU data comprises: Obtaining the maximum and minimum values ​​of the average brightness of all the blocks; A result of dividing the minimum value and the maximum value is calculated as LRU data of the display panel.

7. A display panel brightness uniformity measurement device, characterized in that: include: An image acquisition module, used to acquire a target image of a display panel captured by a camera, wherein the display panel displays a specified grayscale image; An area of ​​interest acquisition module, used to acquire an area of ​​interest of a display panel in the target image; A partitioning module, used for dividing the region of interest of the display panel into N blocks according to the required number of test points N; An average brightness determination module, used to determine the average brightness of each of the blocks according to the brightness data of all pixels in each of the blocks; The LRU determination module is used to determine that the brightness of the display panel is consistent with LRU data according to the average brightness of all the blocks.

8. An electronic device, characterized in that: include: A processor, a memory, and a program stored in the memory and executable on the processor, wherein when the program is executed by the processor, the steps of the method for measuring the brightness uniformity of a display panel as claimed in any one of claims 1 to 6 are implemented.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method for measuring brightness uniformity of a display panel according to any one of claims 1 to 6 are implemented.

10. A computer program product, characterized in that The method comprises computer instructions, which, when executed by a processor, implement the steps of the method for measuring the brightness uniformity of a display panel as claimed in any one of claims 1 to 6.

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