Focus evaluation method, device, equipment and readable storage medium

Abstract

The application provides a focusing evaluation method, device and equipment and a readable storage medium. The method comprises the following steps: obtaining a first image by capturing a preset picture displayed on a display screen by a camera, wherein the preset picture comprises a plurality of points arranged in a matrix form; performing a point spacing reduction operation on the first image to obtain a second image; segmenting the second image to obtain a plurality of sub-images; performing two-dimensional Fourier transform on each sub-image to obtain four alternating components and one direct current component corresponding to each sub-image; and obtaining a focusing evaluation value corresponding to each sub-image based on the four alternating components and the one direct current component corresponding to each sub-image. Through the application, the focusing state of an optical system for different regions on a display screen is quantified, and the preset picture is an existing picture in a Demura repair process, without the need to add a new picture.

Description

Technical Field

[0001] This invention relates to the field of optical technology, and in particular to a focus evaluation method, apparatus, device, and readable storage medium. Background Technology

[0002] Due to the complexity and difficulty of display panel manufacturing processes, Mura defects on display panels are difficult to avoid. Therefore, Mura defects need to be repaired before display panels enter the market, i.e., by applying Demura technology. During the Demura process, the focusing state of the optical system has a significant impact on foreign object detection and Mura repair. Therefore, there is an urgent need for a method to quantitatively evaluate the focusing state of the optical system. Summary of the Invention

[0003] To enable quantitative evaluation of the focusing status of an optical system, this invention provides a focusing evaluation method, apparatus, device, and readable storage medium.

[0004] In a first aspect, the present invention provides a focus evaluation method, the focus evaluation method comprising:

[0005] A first image is obtained by the camera capturing a preset scene displayed on the screen, wherein the preset scene includes a number of points arranged in a matrix.

[0006] The first image is subjected to a pixel spacing reduction operation to obtain the second image;

[0007] The second image is segmented to obtain multiple sub-images;

[0008] Perform a two-dimensional Fourier transform on each sub-image to obtain four AC components and one DC component for each sub-image;

[0009] Based on the four AC components and one DC component corresponding to each sub-image, the focus evaluation value corresponding to each sub-image is obtained.

[0010] Optionally, the step of segmenting the second image to obtain multiple sub-images includes:

[0011] The second image is segmented based on the region of interest to obtain multiple sub-images, each of which contains a region of interest.

[0012] Optionally, the step of obtaining the focus evaluation value corresponding to each sub-image based on the four AC components and one DC component corresponding to each sub-image includes:

[0013] Substituting the four AC components and one DC component corresponding to each sub-image into the focus evaluation value calculation formula, the focus evaluation value of each sub-image is obtained. The focus evaluation value calculation formula is as follows:

[0014]

[0015] Where a1~a4 are four AC components, V is a DC component, and f is the focus evaluation value.

[0016] Optionally, after the step of obtaining the focus evaluation value of each sub-image based on the four AC components and one DC component corresponding to each sub-image, the method further includes:

[0017] The steps include changing the lens focal length of the camera and returning to the first image obtained by the camera capturing a preset image displayed on the screen, wherein the preset image includes several points arranged in a matrix.

[0018] Optionally, the focus evaluation method further includes:

[0019] Based on the focus evaluation value corresponding to each sub-image under different lens focal lengths, a focus evaluation curve corresponding to each sub-image is plotted in a preset coordinate system, where the horizontal axis of the preset coordinate system is the lens focal length and the vertical axis is the focus evaluation value.

[0020] Secondly, the present invention also provides a focus evaluation device, the focus evaluation device comprising:

[0021] The acquisition module is used to acquire a first image obtained by the camera taking a picture of a preset scene displayed on the screen. The preset scene includes a number of points arranged in a matrix.

[0022] The first processing module is used to reduce the pixel spacing of the first image to obtain the second image;

[0023] The segmentation module is used to segment the second image to obtain multiple sub-images;

[0024] The second processing module is used to perform a two-dimensional Fourier transform on each sub-image to obtain four AC components and one DC component corresponding to each sub-image.

[0025] The evaluation module is used to obtain the focus evaluation value for each sub-image based on the four AC components and one DC component corresponding to each sub-image.

[0026] Optionally, the segmentation module is used for:

[0027] The second image is segmented based on the region of interest to obtain multiple sub-images, each of which contains a region of interest.

[0028] Optionally, the evaluation module is used for:

[0029] Substituting the four AC components and one DC component corresponding to each sub-image into the focus evaluation value calculation formula, the focus evaluation value of each sub-image is obtained. The focus evaluation value calculation formula is as follows:

[0030]

[0031] Where a1~a4 are four AC components, V is a DC component, and f is the focus evaluation value.

[0032] Thirdly, the present invention also provides a focus evaluation device, the focus evaluation device including a processor, a memory, and a focus evaluation program stored in the memory and executable by the processor, wherein when the focus evaluation program is executed by the processor, the steps of the focus evaluation method as described above are implemented.

[0033] Fourthly, the present invention also provides a readable storage medium storing a focus evaluation program, wherein when the focus evaluation program is executed by a processor, it implements the steps of the focus evaluation method as described above.

[0034] In this invention, a first image is obtained by capturing a preset scene displayed on a screen using a camera. The preset scene includes several points arranged in a matrix. The first image is then subjected to a point spacing reduction operation to obtain a second image. The second image is then segmented to obtain multiple sub-images. A two-dimensional Fourier transform is performed on each sub-image to obtain four AC components and one DC component corresponding to each sub-image. Based on the four AC components and one DC component corresponding to each sub-image, a focus evaluation value corresponding to each sub-image is obtained. Through this invention, the focus state of the optical system for different areas on the display screen is quantified, and the preset scene is an existing scene in the existing Demura restoration process, eliminating the need to add new scenes. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the hardware structure of the focus evaluation device involved in the embodiment of the present invention;

[0036] Figure 2 This is a flowchart illustrating the first embodiment of the focus evaluation method of the present invention;

[0037] Figure 3 This is a schematic diagram of segmenting the second image;

[0038] Figure 4 This is a flowchart illustrating the second embodiment of the focus evaluation method of the present invention;

[0039] Figure 5 This is a schematic diagram of the focus evaluation curve corresponding to a sub-image.

[0040] Figure 6 This is a schematic diagram of the functional modules of an embodiment of the focus evaluation device of the present invention.

[0041] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0042] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0043] In a first aspect, embodiments of the present invention provide a focus evaluation device, which may be a device with data processing capabilities such as a personal computer (PC), a laptop computer, or a server.

[0044] Reference Figure 1 , Figure 1 This is a schematic diagram of the hardware structure of the focus evaluation device involved in the embodiment of the present invention. In this embodiment, the focus evaluation device may include a processor 1001 (e.g., a Central Processing Unit, CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. The communication bus 1002 is used to realize communication between these components; the user interface 1003 may include a display screen or an input unit such as a keyboard; the network interface 1004 may optionally include a standard wired interface or a wireless interface (e.g., Wireless Fidelity, Wi-Fi interface); the memory 1005 may be high-speed random access memory (RAM) or stable memory (non-volatile memory), such as a disk storage device; the memory 1005 may also optionally be a storage device independent of the aforementioned processor 1001. Those skilled in the art will understand that… Figure 1 The hardware structure shown does not constitute a limitation of the invention and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0045] Continue to refer to Figure 1 , Figure 1 The memory 1005, which serves as a computer storage medium, may include an operating system, a network communication module, a user interface module, and a focus evaluation program. The processor 1001 can call the focus evaluation program stored in the memory 1005 and execute the focus evaluation method provided in this embodiment of the invention.

[0046] Secondly, embodiments of the present invention provide a focus evaluation method.

[0047] In one embodiment, reference is made to Figure 2 , Figure 2 This is a schematic flowchart of an embodiment of the focus evaluation method of the present invention. Figure 2 As shown, the focus evaluation methods include:

[0048] Step S10: Obtain a first image obtained by the camera taking a picture of a preset screen displayed on the screen. The preset screen includes several points arranged in a matrix.

[0049] In this embodiment, when a preset image is displayed on the screen, a camera is used to capture the screen to obtain a first image. The preset image includes several points arranged in a matrix. It should be noted that in the existing Demura restoration process, the screen is controlled to display this preset image. Therefore, the focus evaluation method provided in this embodiment can be well integrated with the existing Demura restoration process.

[0050] Step S20: Reduce the pixel spacing of the first image to obtain the second image;

[0051] In this embodiment, the first image is subjected to a pixel spacing reduction operation, resulting in a more compact arrangement of the pixels, thus obtaining the second image. Specifically, for example, if the horizontal and vertical spacing between pixels in the first image is both A, after the pixel spacing reduction operation, the horizontal and vertical spacing between pixels becomes one-third of A. It should be noted that this is only an illustrative explanation of the pixel spacing reduction operation, and the specific reduction ratio is set according to actual needs.

[0052] Step S30: Segment the second image to obtain multiple sub-images;

[0053] In this embodiment, the segmentation of the second image needs to be based on the region of interest. For example, if the region of interest is the upper left region and the center region of the display screen, then the upper left region and the center region are segmented from the second image.

[0054] Further, in one embodiment, step S30 includes:

[0055] The second image is segmented based on the region of interest to obtain multiple sub-images, each of which contains a region of interest.

[0056] In this embodiment, the regions of interest are preset based on actual needs. For example, if the regions of interest are the upper left, upper right, lower left, lower right, and center regions, then the second image is divided into the upper left, upper right, lower left, lower right, and center regions, resulting in five sub-images. (Refer to...) Figure 3 , Figure 3This is a schematic diagram illustrating the segmentation of the second image. (For example...) Figure 3 As shown, sub-images 1 to 5 are multiple sub-images obtained after segmenting the second image based on the region of interest.

[0057] Step S40: Perform a two-dimensional Fourier transform on each sub-image to obtain four AC components and one DC component corresponding to each sub-image.

[0058] In this embodiment, a two-dimensional Fourier transform is performed on each sub-image. For example, a two-dimensional Fourier transform is performed on sub-images 1 to 5 to obtain the four AC components and one DC component corresponding to sub-image 1, the four AC components and one DC component corresponding to sub-image 2, ..., and the four AC components and one DC component corresponding to sub-image 5.

[0059] Step S50: Based on the four AC components and one DC component corresponding to each sub-image, obtain the focus evaluation value corresponding to each sub-image.

[0060] In this embodiment, based on the four AC components and one DC component corresponding to each sub-image, the focus evaluation value corresponding to each sub-image can be obtained through relevant calculations.

[0061] It is easy to understand that each sub-image represents a specific display area, and the focus evaluation value corresponding to each sub-image is obtained to characterize the focus state of the optical system for the specific display area corresponding to each sub-image. This is of great significance to Demura's industrial production and helps to adjust the optical system to its optimal state.

[0062] Further, in one embodiment, step S50 includes:

[0063] Substituting the four AC components and one DC component corresponding to each sub-image into the focus evaluation value calculation formula, the focus evaluation value of each sub-image is obtained. The focus evaluation value calculation formula is as follows:

[0064]

[0065] Where a1~a4 are four AC components, V is a DC component, and f is the focus evaluation value.

[0066] In this embodiment, the focus evaluation value of each sub-image can be obtained by substituting the four AC components and one DC component corresponding to each sub-image into the above focus evaluation value calculation formula.

[0067] In this embodiment, a first image is obtained by capturing a preset scene displayed on the screen using a camera. The preset scene includes several points arranged in a matrix. The first image is then subjected to a pixel spacing reduction operation to obtain a second image. The second image is then segmented to obtain multiple sub-images. A two-dimensional Fourier transform is performed on each sub-image to obtain four AC components and one DC component corresponding to each sub-image. Based on the four AC components and one DC component corresponding to each sub-image, a focus evaluation value corresponding to each sub-image is obtained. Through this invention, the focus state of the optical system for different areas on the display screen is quantified, and the preset scene is an existing scene in the existing Demura restoration process, eliminating the need to add new scenes.

[0068] Furthermore, in one embodiment, reference is made to Figure 4 , Figure 4 This is a flowchart illustrating the second embodiment of the focus evaluation method of the present invention. Figure 4 As shown, after step S50, the following steps are also included:

[0069] The steps include changing the lens focal length of the camera and returning to the first image obtained by the camera capturing a preset image displayed on the screen, wherein the preset image includes several points arranged in a matrix.

[0070] In this embodiment, multiple lens focal lengths can be preset, such as: 1.5, 1.75, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 4.0, 5.0, 7.5, 10.0. First, set the camera lens focal length to 1.5 and execute steps S10 to S50 to obtain the focus evaluation value for each sub-image when the camera lens focal length is 1.5. This value is used to characterize the focus state of the specific display screen area corresponding to each sub-image when the camera lens focal length is 1.5. Then, set the camera lens focal length to 1.75 and execute steps S10 to S50 to obtain the focus evaluation value for each sub-image when the camera lens focal length is 1.5. This value is used to characterize the focus state of the specific display screen area corresponding to each sub-image when the camera lens focal length is 1.75. By analogy, the focus evaluation value for each sub-image when the camera lens focal length is different can be obtained.

[0071] Furthermore, in one embodiment, the focus evaluation method further includes:

[0072] Based on the focus evaluation value corresponding to each sub-image under different lens focal lengths, a focus evaluation curve corresponding to each sub-image is plotted in a preset coordinate system, where the horizontal axis of the preset coordinate system is the lens focal length and the vertical axis is the focus evaluation value.

[0073] In this embodiment, based on the previous embodiment, the focus evaluation value corresponding to each sub-image is obtained when the camera lens focal length is different. Taking sub-image 1 corresponding to the upper left region as an example, the focus evaluation value corresponding to sub-image 1 when the camera lens focal length is different can be used to plot the focus evaluation curve corresponding to each sub-image in a preset coordinate system, where the horizontal axis of the preset coordinate system is the lens focal length and the vertical axis is the focus evaluation value. Similarly, the focus evaluation curve corresponding to each sub-image can be obtained.

[0074] Reference Figure 5 , Figure 5 This is a schematic diagram of the focus evaluation curve corresponding to a sub-image. From Figure 5 As shown in the focus evaluation curve, the focus evaluation value corresponding to this sub-image first increases and then decreases as the camera lens focal length increases. If this sub-image corresponds to the upper left corner of the display screen, technicians can intuitively understand from the focus evaluation curve that the camera's focus on the upper left corner of the display screen gradually improves as the camera lens focal length increases, reaching a peak before decreasing. Furthermore, this focus evaluation curve can determine the optimal lens focal length at which the camera achieves the best focusing effect on the specific area corresponding to this sub-image (i.e., determine the x-coordinate corresponding to the maximum ordinate of the focus evaluation curve).

[0075] Thirdly, embodiments of the present invention also provide a focus evaluation device.

[0076] In one embodiment, reference is made to Figure 6 , Figure 6 This is a functional module diagram of an embodiment of the focus evaluation device of the present invention. Figure 6 As shown, the focus evaluation device includes

[0077] The acquisition module 10 is used to acquire a first image obtained by the camera taking a picture of a preset image displayed on the screen, wherein the preset image includes a number of points arranged in a matrix.

[0078] The first processing module 20 is used to reduce the pixel spacing of the first image to obtain the second image;

[0079] The segmentation module 30 is used to segment the second image to obtain multiple sub-images;

[0080] The second processing module 40 is used to perform a two-dimensional Fourier transform on each sub-image to obtain four AC components and one DC component corresponding to each sub-image.

[0081] Evaluation module 50 is used to obtain the focus evaluation value corresponding to each sub-image based on the four AC components and one DC component corresponding to each sub-image.

[0082] Furthermore, in one embodiment, the segmentation module 30 is used for:

[0083] The second image is segmented based on the region of interest to obtain multiple sub-images, each of which contains a region of interest.

[0084] Furthermore, in one embodiment, the evaluation module 50 is used for:

[0085] Substituting the four AC components and one DC component corresponding to each sub-image into the focus evaluation value calculation formula, the focus evaluation value of each sub-image is obtained. The focus evaluation value calculation formula is as follows:

[0086]

[0087] Where a1~a4 are four AC components, V is a DC component, and f is the focus evaluation value.

[0088] Furthermore, in one embodiment, the focus evaluation device further includes a jump module for:

[0089] The steps include changing the lens focal length of the camera and returning to the first image obtained by the camera capturing a preset image displayed on the screen, wherein the preset image includes several points arranged in a matrix.

[0090] Furthermore, in one embodiment, the focus evaluation device further includes a drawing module, used for:

[0091] Based on the focus evaluation value corresponding to each sub-image under different lens focal lengths, a focus evaluation curve corresponding to each sub-image is plotted in a preset coordinate system, where the horizontal axis of the preset coordinate system is the lens focal length and the vertical axis is the focus evaluation value.

[0092] The functions of each module in the above-mentioned focus evaluation device correspond to the steps in the above-mentioned focus evaluation method embodiment, and their functions and implementation processes will not be described in detail here.

[0093] Fourthly, embodiments of the present invention also provide a readable storage medium.

[0094] The present invention provides a focus evaluation program stored on a readable storage medium, wherein when the focus evaluation program is executed by a processor, it implements the steps of the focus evaluation method described above.

[0095] The method implemented when the focus evaluation procedure is executed can be referred to in various embodiments of the focus evaluation method of the present invention, and will not be repeated here.

[0096] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0097] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0098] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this 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) as described above, and includes several instructions to cause a terminal device to execute the methods described in the various embodiments of the present invention.

[0099] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A focus evaluation method, characterized in that, The focus evaluation method includes: A first image is obtained by the camera capturing a preset scene displayed on the screen, wherein the preset scene includes a number of points arranged in a matrix. The first image is subjected to a pixel spacing reduction operation to obtain the second image; The second image is segmented to obtain multiple sub-images; Perform a two-dimensional Fourier transform on each sub-image to obtain four AC components and one DC component for each sub-image; Based on the four AC components and one DC component corresponding to each sub-image, the focus evaluation value corresponding to each sub-image is obtained. The step of obtaining the focus evaluation value corresponding to each sub-image based on the four AC components and one DC component corresponding to each sub-image includes: Substituting the four AC components and one DC component corresponding to each sub-image into the focus evaluation value calculation formula, the focus evaluation value of each sub-image is obtained. The focus evaluation value calculation formula is as follows: Where a1~a4 are four AC components, V is a DC component, and f is the focus evaluation value.

2. The focus evaluation method as described in claim 1, characterized in that, The steps for segmenting the second image to obtain multiple sub-images include: The second image is segmented based on the region of interest to obtain multiple sub-images, each of which contains a region of interest.

3. The focus evaluation method as described in claim 1, characterized in that, After the step of obtaining the focus evaluation value of each sub-image based on the four AC components and one DC component corresponding to each sub-image, the method further includes: The steps include changing the lens focal length of the camera and returning to the first image obtained by the camera capturing a preset image displayed on the screen, wherein the preset image includes several points arranged in a matrix.

4. The focus evaluation method as described in claim 3, characterized in that, The focus evaluation method also includes: Based on the focus evaluation value corresponding to each sub-image under different lens focal lengths, a focus evaluation curve corresponding to each sub-image is plotted in a preset coordinate system, where the horizontal axis of the preset coordinate system is the lens focal length and the vertical axis is the focus evaluation value.

5. A focus evaluation device, characterized in that, The focus evaluation device includes The acquisition module is used to acquire a first image obtained by the camera taking a picture of a preset scene displayed on the screen. The preset scene includes a number of points arranged in a matrix. The first processing module is used to reduce the pixel spacing of the first image to obtain the second image; The segmentation module is used to segment the second image to obtain multiple sub-images; The second processing module is used to perform a two-dimensional Fourier transform on each sub-image to obtain four AC components and one DC component corresponding to each sub-image. The evaluation module is used to substitute the four AC components and one DC component corresponding to each sub-image into the focus evaluation value calculation formula to obtain the focus evaluation value for each sub-image. The focus evaluation value calculation formula is as follows: Where a1~a4 are four AC components, V is a DC component, and f is the focus evaluation value.

6. The focus evaluation device as described in claim 5, characterized in that, The segmentation module is used for: The second image is segmented based on the region of interest to obtain multiple sub-images, each of which contains a region of interest.

7. A focus evaluation device, characterized in that, The focus evaluation device includes a processor, a memory, and a focus evaluation program stored in the memory and executable by the processor, wherein when the focus evaluation program is executed by the processor, it implements the steps of the focus evaluation method as described in any one of claims 1 to 4.

8. A readable storage medium, characterized in that, The readable storage medium stores a focus evaluation program, wherein when the focus evaluation program is executed by a processor, it implements the steps of the focus evaluation method as described in any one of claims 1 to 4.

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