Display unevenness compensation device and display unevenness compensation method

Abstract

A display unevenness compensation apparatus for detecting display unevenness of an image displayed through a display panel and compensating for the detected display unevenness according to an embodiment of the present invention comprises: a test image supply unit for supplying first image data and second image data to the display panel; and a test image capturing unit for capturing each of a first image and a second image displayed on the display panel in response to the first image data and the second image data.

Description

Technical Field

[0001] Representative display devices that display images include a liquid crystal display (LCD) using liquid crystals and an organic light emitting diode (OLED) display using organic light emitting diodes.

[0002] Such display panels may have defects in which bright spots or stains are visible in certain pixels or areas of the display panel due to irregularities in the manufacturing process. Background Art

[0003] The present invention is intended to solve the above problems, and its technical goal is to provide a display unevenness (mura) compensation device and a display unevenness compensation method for minimizing defects in which bright spots or stains are visible in specific pixels and some areas due to unevenness in the manufacturing process of a display panel. Summary of the invention

[0004] Technical issues

[0005] The present invention aims to solve the above problems, and its technical goal is to provide a display unevenness compensation device and a display unevenness compensation method for minimizing defects in which bright spots or stains are visible in specific pixels and some areas due to unevenness in the manufacturing process of a display panel.

[0006] Technical Solutions

[0007] A display unevenness compensation device for detecting display unevenness in an image displayed on a display panel and compensating for the detected display unevenness may include: a test image supply part, the test image supply part is configured to supply first image data and second image data to the display panel; and a test image capture part, the test image capture part is configured to capture a first image and a second image displayed on the display panel corresponding to the first image data and the second image data, respectively, wherein the test image capture part may be configured to generate first captured image data by capturing a first image within a first reference exposure time, and to generate second captured image data by capturing a second image within a second reference exposure time, and the second reference exposure time is different from the first reference exposure time.

[0008] Effects of the Invention

[0009] The display unevenness compensating apparatus and the display unevenness compensating method according to the embodiments of the present invention can minimize defects in which bright spots or stains are visible in specific pixels and some areas due to irregularities in a display panel manufacturing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1FIG. 1 is a diagram illustrating a process of detecting display unevenness of a display panel by using the display unevenness compensating apparatus according to an embodiment of the present invention.

[0011] Figure 2 is a block diagram of a display unevenness compensation apparatus according to an embodiment of the present invention.

[0012] Figure 3a to Figure 3c is a diagram showing a process of generating representative image data for each grayscale according to an embodiment of the present invention.

[0013] Figure 4 is a graph showing a low grayscale display unevenness compensation equation for generating low grayscale representative image data according to an embodiment of the present invention.

[0014] Figure 5 is a graph illustrating a process of generating low-grayscale representative image data by using a low-grayscale display unevenness compensation equation according to an embodiment of the present invention.

[0015] Figure 6 is a flowchart of a process for generating representative image data for each grayscale according to an embodiment of the present invention.

[0016] Figure 7 is a flowchart of a process for generating a display unevenness compensation equation for each grayscale and generating low grayscale representative image data based on the generated display unevenness compensation equation according to an embodiment of the present invention. DETAILED DESCRIPTION

[0017] Throughout the specification, the same reference numerals refer to substantially the same components. In the following description, if the configurations and features known in the prior art are not related to the core configuration of the present invention, their detailed description may be omitted. The terms used in this specification should be understood as follows.

[0018] According to the embodiments described in detail below in conjunction with the accompanying drawings, the advantages and features of the present invention and the methods for achieving them will become apparent. However, the present invention is not limited to the following embodiments, but can be implemented in various forms; more specifically, these embodiments are provided to complete the description of the present invention and allow those skilled in the art to fully understand the scope of the present invention, and the present invention is only limited within the scope of the appended claims.

[0019] The shapes, sizes, proportions, angles, quantities, etc. shown in the accompanying drawings for illustrating the embodiments of the present invention are merely examples, and the present invention is not limited thereto. Throughout the specification, the same reference numerals may represent the same components. In addition, when describing the present invention, if the detailed description of the known related art is considered to unnecessarily obscure the main points of the present invention, it may be omitted.

[0020] As used herein, terms such as "includes," "comprising," "having," and "consisting of" are generally intended to allow for the addition of other components unless these terms are used with the term "only." Reference to components of a singular noun includes the plural of that noun unless expressly stated otherwise.

[0021] When interpreting the components, they are interpreted as including the margin of error even if not explicitly stated.

[0022] When describing a temporal context, for example, such as "after", "subsequently", "after", or "before", it may also include discontinuous cases unless "immediately" or "directly" is used.

[0023] First, second, etc. are used to describe various components, but these components are not limited by these terms. These terms are only used to distinguish one component from another component. Therefore, within the technical concept of the present invention, the first component mentioned herein may also be the second component.

[0024] It should be understood that the term "at least one" includes any combination that can be cited from one or more related items. For example, the phrase "at least one of the first, second, and third items" can mean each of the first, second, or third items, and any combination of items that can be cited from two or more of the first, second, and third items.

[0025] Each of the features of the various embodiments of the present invention may be coupled or combined with each other in whole or in part, and may be technically interlocked and operated in various ways, and each of these embodiments may be implemented independently or in combination with each other. Figures 1 to 5 A display unevenness compensating apparatus according to an embodiment of the present invention is described in detail.

[0026] Figure 1 is a diagram showing a process of detecting display unevenness of a display panel by using a display unevenness compensation device according to an embodiment of the present disclosure, and Figure 2 is a block diagram of a display unevenness compensation apparatus according to an embodiment of the present invention. Figure 3a to Figure 3c is a diagram showing a process of generating representative image data for each grayscale according to an embodiment of the present disclosure, and Figure 4 is a diagram illustrating a low grayscale display unevenness compensation equation for generating low grayscale representative image data according to an embodiment of the present invention. Figure 5 is a graph illustrating a process of generating low-grayscale representative image data by using a low-grayscale display unevenness compensation equation according to an embodiment of the present invention.

[0027] refer to Figure 1The display unevenness compensation device 200 provides test image data to the display panel 100, measures display unevenness by taking a photo of an image displayed on the display panel 100, calculates a compensation value for compensating the measured display unevenness, and provides the calculated compensation value to the driver 300 that drives the display panel 100.

[0028] In this case, the display panel 100 may display an image having a specific grayscale by using light irradiated from the backlight unit. The display panel 100 may be a flat display panel such as a liquid crystal display (LCD) panel or an organic light emitting diode (OLED) display panel.

[0029] Although not shown, the display panel 100 includes a plurality of gate lines, a plurality of data lines, and a plurality of pixels. Each of the plurality of gate lines receives a scan pulse. Each of the plurality of data lines receives a data signal during a display period (DP). The plurality of gate lines and the plurality of data lines are arranged to cross each other on a substrate to define a plurality of pixels. Each of the plurality of pixels may include a thin film transistor connected to adjacent gate lines and data lines, a pixel electrode connected to the thin film transistor, and a storage capacitor connected to the pixel electrode.

[0030] The pixels of the display panel 100 may include sub-pixels of a first color, sub-pixels of a second color, and sub-pixels of a third color, and may also include sub-pixels of a fourth color. Here, the first color may be one of red (R), green (G), and blue (B), the second color may be the other of red (R), green (G), and blue (B), and the third color may be the other of red (R), green (G), and blue (B). In addition, the fourth color may be white (W). For example, the sub-pixels may be repeatedly formed in the row direction, or may be formed in a 2*2 matrix form. In this case, the color filters corresponding to the respective colors are arranged in the sub-pixels of the first color, the sub-pixels of the second color, and the sub-pixels of the third color, and no separate color filter is arranged in the sub-pixels of the fourth color. In one embodiment, the sub-pixels of the first color, the sub-pixels of the second color, the sub-pixels of the third color, and the sub-pixels of the fourth color may be formed to have the same area ratio, but may also be formed to have different area ratios.

[0031] Due to irregularities in the manufacturing process, the display panel 100 may display bright spots or stains in some pixels or regions. According to an embodiment of the present invention, the display quality of the display panel 100 can be improved by compensating for such display defects in the display panel 100.

[0032] like Figure 1 and Figure 2As shown, the display unevenness compensating apparatus 200 according to the embodiment of the present invention includes a test image supplying part 210 , a test image capturing part 220 , and a display unevenness compensating part 230 .

[0033] The test image supplying part 210 provides image data to the display panel 100. According to an embodiment of the present invention, the test image supplying part 210 may provide a plurality of pieces of image data corresponding to a specific grayscale range to the display panel 100. In this case, the plurality of pieces of image data may be composed of image data of respective pixels input to the display panel 100. Specifically, as Figure 2 As shown, the test image supply part 210 provides the display panel 100 with first to third low grayscale image data (L_IMG1, L_IMG2, L_IMG3), first to third medium grayscale image data (M_IMG1, M_IMG2, M_IMG3), and first to third high grayscale image data (H_IMG1, H_IMG2, H_IMG3).

[0034] The first low-grayscale image data to the third low-grayscale image data (L_IMG1, L_IMG2, L_IMG3) may have a grayscale lower than or equal to the first medium-grayscale image data to the third medium-grayscale image data (M_IMG1, M_IMG2, M_IMG3) and the first high-grayscale image data to the third high-grayscale image data (H_IMG1, H_IMG2, H_IMG3), and the first medium-grayscale image data to the third medium-grayscale image data (M_IMG1, M_IMG2, M_IMG3) may have a grayscale lower than or equal to the first high-grayscale image data to the third high-grayscale image data (H_IMG1, H_IMG2, H_IMG3).

[0035] According to an embodiment of the present invention, the first low-grayscale image data to the third low-grayscale image data (L_IMG1, L_IMG2, L_IMG3) may have different grayscales, the first medium-grayscale image data to the third medium-grayscale image data (M_IMG1, M_IMG2, M_IMG3) may have different grayscales, and the first high-grayscale image data to the third high-grayscale image data (H_IMG1, H_IMG2, H_IMG3) may have different grayscales. For example, the first low-grayscale image data (L_IMG1) may have a grayscale lower than the grayscales of the second low-grayscale image data (L_IMG2) and the third low-grayscale image data (L_IMG3), the second low-grayscale image data (L_IMG2) may have a grayscale lower than the grayscale of the third low-grayscale image data (L_IMG3), and the grayscale difference between the second low-grayscale image data (L_IMG2) and the first low-grayscale image data (L_IMG1) may be the same as the grayscale difference between the third low-grayscale image data (L_IMG3) and the second low-grayscale image data (L_IMG2). The first middle-grayscale image data (M_IMG1) may have a grayscale lower than the grayscales of the second middle-grayscale image data (M_IMG2) and the third middle-grayscale image data (M_IMG3), the second middle-grayscale image data (M_IMG2) may have a grayscale lower than the grayscale of the third middle-grayscale image data (M_IMG3), and the grayscale difference between the second middle-grayscale image data (M_IMG2) and the first middle-grayscale image data (M_IMG1) may be the same as the grayscale difference between the third middle-grayscale image data (M_IMG3) and the second middle-grayscale image data (M_IMG2). In addition, the first high grayscale image data (H_IMG1) may have a grayscale lower than the grayscale of the second high grayscale image data (H_IMG2) and the third high grayscale image data (H_IMG3), the second high grayscale image data (H_IMG2) may have a grayscale lower than the grayscale of the third high grayscale image data (H_IMG3), and the grayscale difference between the second high grayscale image data (H_IMG2) and the first high grayscale image data (H_IMG1) may be the same as the grayscale difference between the third high grayscale image data (H_IMG3) and the second high grayscale image data (H_IMG2). In this case, the grayscale difference between the low grayscale image data may be smaller than the grayscale difference between the medium grayscale image data and the grayscale difference between the high grayscale image data, and the grayscale difference between the medium grayscale image data may be smaller than the grayscale difference between the high grayscale image data.

[0036] For example, the first low-grayscale image data (L_IMG1) may be image data consisting of image data of 20 grays, the second low-grayscale image data (L_IMG2) may be image data consisting of image data of 30 grays, the third low-grayscale image data (L_IMG3) may be image data consisting of image data of 40 grays, the first medium-grayscale image data (M_IMG1) may be image data consisting of image data of 40 grays, the second medium-grayscale image data (M_IMG2) may be image data consisting of image data of 60 grays, the third medium-grayscale image data (M_IMG3) may be image data consisting of image data of 80 grays, the first high-grayscale image data (H_IMG1) may be image data consisting of image data of 150 grays, the second high-grayscale image data (H_IMG2) may be image data consisting of image data of 180 grays, and the third high-grayscale image data (H_IMG3) may be image data consisting of image data of 210 grays. Therefore, the absolute value of the difference between the low grayscale image data (L_IMG1, L_IMG2, L_IMG3) (which is 10 grays) may be smaller than the absolute value of the difference between the middle grayscale image data (M_IMG1, M_IMG2, M_IMG3) (which is 20 grays) and the absolute value of the difference between the high grayscale image data (H_IMG1, H_IMG2, H_IMG3) (which is 30 grays), and the absolute value of the difference between the middle grayscale image data (M_IMG1, M_IMG2, M_IMG3) (which is 20 grays) may be smaller than the absolute value of the difference between the high grayscale image data (H_IMG1, H_IMG2, H_IMG3) (which is 30 grays). In addition, for example, the low grayscale image data (L_IMG1, L_IMG2, L_IMG3) may have a grayscale value of 0 or greater and less than 45, the medium grayscale image data (M_IMG1, M_IMG2, M_IMG3) may have a grayscale value of 20 or greater and less than 100, and the high grayscale image data (H_IMG1, H_IMG2, H_IMG3) may have a grayscale value of 100 or greater.

[0037] The display panel 100 receives first to third low grayscale image data (L_IMG1, L_IMG2, L_IMG3), first to third medium grayscale image data (M_IMG1, M_IMG2, M_IMG3), and first to third high grayscale image data (H_IMG1, H_IMG2, H_IMG3) from the test image supply part 210, and displays first to third low grayscale images, first to third medium grayscale images, and first to third high grayscale images, respectively.

[0038] The test image capturing part 220 captures an image displayed on the display panel 100 to obtain captured image data. In this case, according to an embodiment of the present invention, the test image capturing part 220 captures the first low grayscale image to the third low grayscale image by applying the same reference exposure time, captures the first medium grayscale image to the third medium grayscale image by applying the same reference exposure time, captures the first high grayscale image to the third high grayscale image by applying the same reference exposure time, and captures the image displayed on the display panel 100 by applying different reference exposure times to the first low grayscale image to the third low grayscale image, the first medium grayscale image to the third medium grayscale image, and the first high grayscale image to the third high grayscale image. Therefore, the test image capturing part 220 generates a plurality of captured image data. Specifically, the test image capturing part 220 captures the display panel 100 displaying the first low grayscale image to the third low grayscale image within the first reference exposure time (t_exp1) to generate the first low grayscale captured image data to the third low grayscale captured image data (L_capIMG1, L_capIMG2, L_capIMG3), captures the display panel 100 displaying the first medium grayscale image to the third medium grayscale captured image data (M_capIMG1, M_capIMG2, M_capIMG3) within the second reference exposure time (t_exp2) to generate the first medium grayscale captured image data to the third medium grayscale captured image data (M_capIMG1, M_capIMG2, M_capIMG3), and captures the display panel 100 displaying the first high grayscale image to the third high grayscale image within the third reference exposure time (t_exp3) to generate the first high grayscale captured image data to the third high grayscale captured image data (H_capIMG1, H_capIMG2, H_capIMG3). In this case, according to an embodiment of the present invention, the first reference exposure time (t_exp1) may be a value greater than the second reference exposure time (t_exp2) and the third reference exposure time (t_exp3), and the second reference exposure time (t_exp2) may be a value greater than the third reference exposure time (t_exp3). For example, the first reference exposure time (t_exp1) may be 40 milliseconds, the second reference exposure time (t_exp2) may be 30 milliseconds, and the third reference exposure time (t_exp3) may be 15 milliseconds. These first reference exposure time to the third reference exposure time (t_exp1, t_exp2, t_exp3) may be generated by the display unevenness compensation part 230 to be described later.

[0039] The test image capturing part 220 captures an image displayed on the display panel 100 to generate captured image data, and forwards the captured image data to the display unevenness compensating part 230 .

[0040] To this end, the test image capturing part 220 can be implemented by a camera, a colorimeter, etc., and can be composed of, for example, a CCD sensor, a lens, and a body. In particular, according to an embodiment of the present invention, the test image capturing part 220 can set a reference exposure time according to the above grayscale range.

[0041] In addition, the captured image data generated by the test image capturing part 220 by photographing the image displayed on the display panel 100 may be composed of image data corresponding to the pixels of the display panel 100. That is, the first low grayscale captured image data to the third low grayscale captured image data (L_capIMG1, L_capIMG2, L_capIMG3), the first middle grayscale captured image data to the third middle grayscale captured image data (M_capIMG1, M_capIMG2, M_capIMG3), and the first high grayscale captured image data to the third high grayscale captured image data (H_capIMG1, H_capIMG2, H_capIMG3) may be composed of image data corresponding to the pixels of the display panel 100.

[0042] The test image capturing part 220 may transmit the captured image data in various formats that can be received by the display unevenness compensating part 230 .

[0043] Although not shown, the display unevenness compensation device 200 may further include a shooting correction part to obtain more accurate captured image data. The shooting correction part may receive the captured image data obtained by shooting the image displayed on the display panel 100 from the test image capture part 220, and correct the shooting state of the test image capture part 220 to prevent errors caused by the test image capture part 220. To this end, the shooting correction part may display correction information for correcting the shooting state on a separate display device according to the analysis result of the captured image data obtained by shooting the image displayed on the display panel 100, or may feed back the correction information to the test image capture part 220. When the shooting correction part displays the correction information on the separate display device, the user may check the correction information and correct the shooting state of the test image capture part 220. Alternatively, the test image capture part 220 may automatically correct the shooting state by referring to the feedback correction information. In this case, the image data used to correct the shooting state of the test image capture part 220 may be an image different from the image data used to analyze the display unevenness of the display panel 100, and the image data used to correct the shooting state may include a pattern that makes it easy to analyze the size of the image, the degree of rotation (tilt) of the image, and the distortion of the image.

[0044] The display unevenness compensation part 230 generates a display unevenness compensation equation for calculating a display unevenness compensation coefficient. Specifically, the display unevenness compensation part 230 calculates a reference exposure time for each grayscale range for capturing an image of the corresponding grayscale range to provide it to the test image capturing part 220, and generates representative image data for each grayscale range to generate a display unevenness compensation equation. To this end, Figure 2 As shown, the display unevenness compensating section 230 includes a reference exposure time calculator 231 , a representative image data generator 232 , and a display unevenness compensation equation generator 233 .

[0045] The reference exposure time calculator 231 calculates a first reference exposure time (t_exp1) for capturing a first low-grayscale image to a third low-grayscale image, a second reference exposure time (t_exp2) for capturing a first medium-grayscale image to a third medium-grayscale image, and a third reference exposure time (t_exp3) for capturing a first high-grayscale image to a third high-grayscale image, and provides the calculated exposure time to the test image capturing part 220. The reference exposure time calculator 231 determines the exposure time that makes any one of the first to third low-grayscale image data (L_IMG, L_IMG2, L_IMG3) generated by capturing the first to third low-grayscale images, any one of the first to third medium-grayscale image data (M_IMG1, M_IMG2, M_IMG3) generated by capturing the first to third medium-grayscale images, and any one of the first to third high-grayscale image data (H_IMG1, H_IMG2, H_IMG3) generated by capturing the first to third high-grayscale images unsaturated as the first reference exposure time (t_exp1), the second reference exposure time (t_exp2), and the third reference exposure time (t_exp3). For example, the reference exposure time calculator 231 may determine the exposure time that makes the second low-grayscale image data (L_IMG2) unsaturated as the first reference exposure time (t_exp1), determine the exposure time that makes the second medium-grayscale image data (M_IMG2) unsaturated as the second reference exposure time (t_exp2), and determine the exposure time that makes the second high-grayscale image data (H_IMG2) unsaturated as the third reference exposure time (t_exp3).

[0046] Representative image data generator 232 is as follows Figure 3a to Figure 3cThat is, the representative image data generator 232 generates low grayscale representative image data (L_repIMG) by using the first low grayscale captured image data to the third low grayscale captured image data (L_capIMG1, L_capIMG2, L_capIMG3), generates medium grayscale representative image data (M_repIMG) by using the first medium grayscale captured image data to the third medium grayscale captured image data (M_capIMG1, M_capIMG2, M_capIMG3), and generates high grayscale representative image data (L_repIMG) by using the first high grayscale captured image data to the third high grayscale captured image data (H_capIMG1, H_capIMG2, H_capIMG3).

[0047] Specifically, the representative image data generator 232 calculates Figure 3a The representative brightness code values ​​(L_repIMG1, L_repIMG2, L_repIMG3) for the first to third low grayscale captured image data (L_capIMG1, L_capIMG2, L_capIMG3) are calculated as shown in FIG. Figure 3b The representative brightness code values ​​(M_repIMG1, M_repIMG2, M_repIMG3) for the first to third mid-grayscale captured image data (M_capIMG1, M_capIMG2, M_capIMG3) are shown, and are calculated as follows: Figure 3c Representative luminance code values ​​(H_repIMG1, H_repIMG2, H_repIMG3) for the first to third high grayscale captured image data (H_capIMG1, H_capIMG2, H_capIMG3) are shown. Here, the representative luminance code value may be one of the average value, mode value, and median value of the image data constituting the grayscale specific captured image data. For example, the representative image data generator 232 may calculate 80 grayscales as the average value of image data constituting the first low grayscale captured image data (L_capIMG1) as the first low grayscale representative brightness code value (L_repIMG1), calculate 120 grayscales as the average value of image data constituting the second low grayscale captured image data (L_capIMG2) as the second low grayscale representative brightness code value (L_repIMG2), and calculate 200 grayscales as the average value of image data constituting the third low grayscale captured image data (L_capIMG3) as the third low grayscale representative brightness code value (L_repIMG3).

[0048] The representative image data generator 232 determines a representative image data generation equation for each grayscale by using a representative brightness code value for each grayscale range. Specifically, equation 1 as a low grayscale representative image data generation equation can be derived by using a first low grayscale representative brightness code value (L_repIMG1) of a first low grayscale captured image data (L_capIMG1) obtained by inputting a first low grayscale image data (L_IMG1), a second low grayscale representative brightness code value (L_repIMG2) of a second low grayscale captured image data (L_capIMG2) obtained by inputting a second low grayscale image data (L_IMG2), and a third low grayscale representative brightness code value (L_repIMG3) of a third low grayscale captured image data (L_capIMG3) obtained by inputting a third low grayscale image data (L_IMG3).

[0049] [Equation 1]

[0050] y=a L x 2 +b L x+c L

[0051] In Equation 1, x is a grayscale value input to the display panel 100, and y is a grayscale value of captured image data obtained by photographing an image displayed on the display panel 100. That is, the representative image data generator 232 calculates a of Equation 1 by using the first low grayscale image data (L_IMG1), the first low grayscale representative brightness code value (L_repIMG1), the first low grayscale image data (L_IMG2), the second low grayscale representative brightness code value (L_repIMG2), the first low grayscale image data (L_IMG3), and the third low grayscale representative brightness code value (L_repIMG3). L , b L and c L That is, the first low grayscale image data (L_IMG1) and the first low grayscale representative brightness code value (L_repIMG1) can be applied to x and y in Equation 1, respectively, the second low grayscale image data (L_IMG2) and the second low grayscale representative brightness code value (L_repIMG2) can be applied to x and y in Equation 1, respectively, and the third low grayscale image data (L_IMG3) and the third low grayscale representative brightness code value (L_repIMG3) can be applied to x and y in Equation 1, respectively. L , b L and c L Then, a in Equation 1 can be calculated by using the derived simultaneous equations L , bL and c L , to derive Figure 4 The low grayscale representative image data generation equation for the low grayscale image data is shown.

[0052] Therefore, the representative image data generator 232 may apply one of the first to third low grayscale captured image data (L_capIMG, L_capIMG2, L_capIMG3) to the following Equation 2 (which is a modified form of Equation 1) to generate low grayscale representative image data (L_repIMG) estimated to be ideally displayed on the display panel 100 by excluding the applied display unevenness compensation value of the display panel 100. For example, as described above, each captured image data is composed of image data corresponding to a pixel of the display panel 100, and the representative image data generator 232 may generate the low grayscale representative image data (L_repIMG) by applying Equation 2 (which is a modified form of Equation 1) to each unit block including at least one image data corresponding to a pixel of the display panel 100 for each captured image data.

[0053] [Equation 2]

[0054]

[0055] That is to say, Figure 5 As shown, the representative image data generator 232 generates low grayscale representative image data (L_repIMG) composed of x generated by applying image data of a unit block of the second low grayscale captured image (L_capIMG2) to y in Equation 2.

[0056] Although the representative image data generator 232 has been described based on low grayscale image data (L_IMG1, L_IMG2, L_IMG3), the representative image data generator 232 also utilizes the same method for medium grayscale image data (M_IMG1, M_IMG2, M_IMG3) and high grayscale image data (H_IMG1, H_IMG2, H_IMG3) to generate medium grayscale representative image data (M_repIMG1, M_repIMG2, M_repIMG3) and high grayscale representative image data (H_repIMG1, H_repIMG2, H_repIMG3).

[0057] The display unevenness compensation equation generator 233 generates a display unevenness compensation equation by using the low grayscale representative image data (L_repIMG), the middle grayscale representative image data (L_repIMG), and the high grayscale representative image data (L_repIMG) generated by the representative image data generator 232. Specifically, the display unevenness compensation equation generator 233 calculates a of the following equation 3 using the image data of the low grayscale representative image data (L_repIMG), the middle grayscale representative image data (L_repIMG), and the high grayscale representative image data (L_repIMG) for each unit block including image data corresponding to at least one pixel. F , b F and c F , to generate a display unevenness compensation equation. That is, by applying any one of the first low grayscale image data to the third low grayscale image data (L_IMG1, L_IMG2, L_IMG3) and the low grayscale representative image data (L_repIMG) to x and y of the following equation 3, respectively, applying any one of the first medium grayscale image data to the third medium grayscale image data (M_IMG1, M_IMG2, M_IMG3) and the medium grayscale representative image data (M_repIMG) to x and y of the following equation 3, and applying any one of the first high grayscale image data to the third high grayscale image data (H_IMG1, H_IMG2, H_IMG3) and the high grayscale representative image data (H_repIMG) to x and y of the following equation 3, a is derived for a in equation 3. F , b F and c F The three simultaneous equations, and by calculating a of Equation 3 F , b F and c F To derive the display unevenness compensation equation.

[0058] [Equation 3]

[0059] y=a F x 2 +b F x+c F

[0060] The display unevenness compensation equation generator 233 calculates a compensation coefficient according to an input grayscale for each pixel of the display panel 100 through the display unevenness compensation equation, and provides it to the driver 300 driving the display panel 100 .

[0061] Therefore, the display unevenness compensation device according to an embodiment of the present invention obtains grayscale-specific representative image data (L_repIMG, L_repIMG, L_repIMG) actually displayed on the display panel 100, which is independent of the deviation in the shooting equipment of the test image capturing part 220 and the display panel 100, by using the grayscale-specific captured image data (L_capIMG1, L_capIMG2, L_capIMG3) generated by shooting the display panel 100, and calculates the display unevenness compensation coefficient, so that the display unevenness can be compensated more accurately.

[0062] Next, we will refer to Figure 6 and Figure 7 A detailed description is given of a display unevenness compensating method according to an embodiment of the present invention.

[0063] Figure 6 is a flowchart of a process for generating representative image data for each grayscale according to an embodiment of the present invention, and Figure 7 is a flowchart of a process for generating a display unevenness compensation equation for each grayscale and generating low grayscale representative image data based on the generated display unevenness compensation equation according to an embodiment of the present invention.

[0064] refer to Figure 6, the test image supply part 210 provides the first to third image data for each grayscale range to the display panel 100 (s601). Specifically, as described above, the test image supply part 210 provides the first to third low grayscale image data (L_IMG1, L_IMG2, L_IMG3), the first to third medium grayscale image data (M_IMG1, M_IMG2, M_IMG3), and the first to third high grayscale image data (H_IMG1, H_IMG2, H_IMG3) to the display panel 100. According to an embodiment of the present invention, the first low-grayscale image data to the third low-grayscale image data (L_IMG1, L_IMG2, L_IMG3) may have different grayscales, the first medium-grayscale image data to the third medium-grayscale image data (M_IMG1, M_IMG2, M_IMG3) may have different grayscales, and the first high-grayscale image data to the third high-grayscale image data (H_IMG1, H_IMG2, H_IMG3) may have different grayscales. Specifically, the first low-grayscale image data (L_IMG1) may have a grayscale lower than the grayscale of the second low-grayscale image data (L_IMG2) and the third low-grayscale image data (L_IMG3), the second low-grayscale image data (L_IMG2) may have a grayscale lower than the grayscale of the third low-grayscale image data (L_IMG3), and the grayscale difference between the second low-grayscale image data (L_IMG2) and the first low-grayscale image data (L_IMG1) may be the same as the grayscale difference between the third low-grayscale image data (L_IMG3) and the second low-grayscale image data (L_IMG2). The first middle-grayscale image data (M_IMG1) may have a grayscale lower than the grayscales of the second middle-grayscale image data (M_IMG2) and the third middle-grayscale image data (M_IMG3), the second middle-grayscale image data (M_IMG2) may have a grayscale lower than the grayscale of the third middle-grayscale image data (M_IMG3), and the grayscale difference between the second middle-grayscale image data (M_IMG2) and the first middle-grayscale image data (M_IMG1) may be the same as the grayscale difference between the third middle-grayscale image data (M_IMG3) and the second middle-grayscale image data (M_IMG2). In addition, the first high-grayscale image data (H_IMG1) may have a grayscale lower than the grayscales of the second high-grayscale image data (H_IMG2) and the third high-grayscale image data (H_IMG3), the second high-grayscale image data (H_IMG2) may have a grayscale lower than the grayscale of the third high-grayscale image data (H_IMG3), and the grayscale difference between the second high-grayscale image data (H_IMG2) and the first high-grayscale image data (H_IMG1) may be the same as the grayscale difference between the third high-grayscale image data (H_IMG3) and the second high-grayscale image data (H_IMG2).In this case, the grayscale difference between the low grayscale image data may be smaller than the grayscale difference between the middle grayscale image data and the grayscale difference between the high grayscale image data, and the grayscale difference between the middle grayscale image data may be smaller than the grayscale difference between the high grayscale image data.

[0065] Thereafter, the display panel 100 displays an image corresponding to the received image data for each grayscale range (s602). Specifically, the display panel 100 displays the first low grayscale image to the third low grayscale image data (L_IMG1, L_IMG2, L_IMG3), the first medium grayscale image data to the third medium grayscale image data (M_IMG1, M_IMG2, M_IMG3) and the first high grayscale image data to the third high grayscale image data (H_IMG1, H_IMG2, H_IMG3) corresponding to the received first low grayscale image data to the third low grayscale image data (L_IMG1, L_IMG2, L_IMG3).

[0066] Thereafter, the test image capturing part 220 captures an image displayed on the display panel 100 to generate captured image data (s603). Specifically, the test image capturing part 220 generates first to third low grayscale captured images (L_capIMG1, L_capIMG2, L_capIMG3), first to third medium grayscale captured images (M_capIMG1, M_capIMG2, M_capIMG3), and first to third high grayscale captured images (H_capIMG1, H_capIMG2, H_capIMG3) corresponding to the first to third low grayscale images, the first to third medium grayscale images, and the first to third high grayscale images displayed on the display panel 100, respectively. In this case, the test image capturing part 220 can capture the first low grayscale image to the third low grayscale image by applying the same reference exposure time as the first reference exposure time (t_exp1), capture the first medium grayscale image to the third medium grayscale image by applying the same reference exposure time as the second reference exposure time (t_exp2), capture the first high grayscale image to the third high grayscale image by applying the same reference exposure time as the third reference exposure time (t_exp3), and it can capture the first low grayscale image to the third low grayscale image, the first medium grayscale image to the third medium grayscale image, and the first high grayscale image to the third high grayscale image by applying different reference exposure times. Specifically, the test image capturing part 220 may receive the first to third reference exposure times (t_exp1, t_exp2, t_exp3) from the reference exposure time calculator 231, and may capture the first to third low grayscale images by applying the first reference exposure time (t_exp1), the first to third medium grayscale images by applying the second reference exposure time (t_exp2), and the first to third high grayscale images by applying the third reference exposure time (t_exp3). Here, the first to third reference exposure times (t_exp1, t_exp2, t_exp3) may have different values; specifically, the first reference exposure time (t_exp1) may be a value greater than the second reference exposure time (t_exp2) and the third reference exposure time (t_exp3), and the second reference exposure time (t_exp2) may be a value greater than the third reference exposure time (t_exp3).

[0067] Thereafter, the representative image data generator 232 generates representative image data for each grayscale range by using the captured image data for each grayscale range (s604). Figure 7 Describe in detail.

[0068] refer to Figure 7 , the representative image data generator 232 calculates a representative brightness code value corresponding to each captured image data (s701). Specifically, the representative image data generator 232 calculates one of the average value, mode value, or median value of the image data constituting the captured image data as a representative brightness code value corresponding to the captured image data. For example, the representative image data generator 232 may calculate 80 grayscales as the average value of the image data constituting the first low grayscale captured image data (L_capIMG1) as the first low grayscale representative brightness code value (L_repIMG1), generate 120 grayscales as the average value of the image data constituting the second low grayscale captured image data (L_capIMG2) as the second low grayscale representative brightness code value (L_repIMG2), and generate 200 grayscales as the average value of the image data constituting the third low grayscale captured image data (L_capIMG3) as the third low grayscale representative brightness code value (L_repIMG3).

[0069] Thereafter, the representative image data generator 232 uses the representative brightness code value to determine a representative image data generation equation for each grayscale (s702). Specifically, the representative image data generator 232 uses the first low grayscale representative brightness code value (L_repIMG1) for the first low grayscale captured image data (L_capIMG1), the second low grayscale representative brightness code value (L_repIMG2) for the second low grayscale captured image data (L_capIMG2), and the third low grayscale representative brightness code value (L_repIMG3) for the third low grayscale captured image data (L_capIMG3) to calculate the coefficient a of equation 1. L , b L and c L , to determine the low grayscale representative image data generation equation.

[0070] Afterwards, the representative image data generator 232 applies one of the grayscale range-specific captured image data to Equation 2 (which is a modified form of Equation 1) to generate representative image data for each grayscale range (s703), where Equation 1 is the representative image data generation equation for each grayscale range at step s702. For example, the representative image data generator 232 can generate low grayscale representative image data (L_repIMG) by applying image data corresponding to a unit block of the second low grayscale captured image data (L_capIMG2) to y in Equation 2.

[0071] Steps S702 and S703 have been described based on the low grayscale captured image data, but representative image data is also generated for the medium grayscale captured image data and the high grayscale captured image data by using the same method as for the low grayscale captured image data.

[0072] Return to reference Figure 6 , thereafter, the display unevenness compensation equation generator 233 generates a display unevenness compensation equation by using representative image data specific to a grayscale range (s605). Specifically, the display unevenness compensation equation generator 233 calculates coefficients of Equation 3 by using image data of low grayscale representative image data (L_repIMG), medium grayscale representative image data (L_repIMG), and high grayscale representative image data (L_repIMG) for each unit block including image data corresponding to at least one pixel, thereby generating a display unevenness compensation equation.

[0073] Those skilled in the art to which the present invention pertains will appreciate that the present invention described above may be implemented in other specific forms without changing its technical concept or essential features.

[0074] In addition, the methods described herein may be implemented at least in part using one or more computer programs or components. The components may be provided as a collection of computer instructions on a computer-readable medium or machine-readable medium, and the computer-readable medium includes volatile memory and non-volatile memory. The above instructions may be provided as software or firmware, and may be implemented in whole or in part in a hardware configuration such as an ASIC, FPGA, DSP or other similar device. The above instructions may be configured to be executed by one or more processors or other hardware configurations, which, when executing the above set of computer instructions, execute or cause execution of all or part of the methods and processes disclosed herein.

[0075] Therefore, it should be understood that the above embodiments are illustrative in all aspects and do not limit the present invention. The scope of the present invention is represented by the appended claims rather than the specific embodiments above, and it should be understood that all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts are included in the scope of the present invention.

[0076] Mode for Carrying Out the Invention

[0077] Various modes of embodiment of the present invention have been described in the foregoing subheading "Detailed Description of the Invention".

[0078] Industrial Applicability

[0079] The present invention is an example of a display device for displaying an image, and is applicable to LCD, OLED, etc. without limitation, and is therefore considered to have industrial use.

Claims

1. A display unevenness compensation device, the display unevenness compensation device is used to detect display unevenness in an image displayed on a display panel and compensate for the detected display unevenness, the display unevenness compensation device comprising: a test image supplying section configured to supply first image data and second image data to the display panel; a test image capturing section configured to capture a first image and a second image displayed on the display panel corresponding to the first image data and the second image data, respectively; as well as Display uneven compensation part, wherein the test image capturing section is configured to generate first captured image data by capturing the first image within a first reference exposure time, and to generate second captured image data by capturing the second image within a second reference exposure time, the second reference exposure time being different from the first reference exposure time, and The display unevenness compensating portion is configured to compensate for the display unevenness by using the first captured image data and the second captured image data.

2. The display unevenness compensation device according to claim 1, wherein: The display unevenness compensating section is configured to generate first representative image data based on the first captured image data, generate second representative image data based on the second captured image data, and compensate for the display unevenness by using the first representative image data and the second representative image data.

3. The display unevenness compensation device according to claim 2, wherein: The first image data includes first low-grayscale image data and second low-grayscale image data; The second image data includes first high grayscale image data and second high grayscale image data; The first captured image data includes first low grayscale captured image data and second low grayscale captured image data; The second captured image data includes first high grayscale captured image data and second high grayscale captured image data; and The display unevenness compensation part is configured to calculate a first low grayscale representative brightness code value and a second low grayscale representative brightness code value for the first low grayscale captured image data and the second low grayscale captured image data, respectively, generate the first representative image data by using the calculated first low grayscale representative brightness code value and the second low grayscale representative brightness code value, calculate a first high grayscale representative brightness code value and a second high grayscale representative brightness code value for the first high grayscale captured image data and the second high grayscale captured image data, respectively, and generate the second representative image data by using the calculated first high grayscale representative brightness code value and the second high grayscale representative brightness code value.

4. The display unevenness compensation device according to claim 1, wherein: The first low grayscale representative brightness code value and the second low grayscale representative brightness code value and the first high grayscale representative brightness code value and the second high grayscale representative brightness code value are each one of the average value, the mode value and the median value of the image data constituting each of the first low grayscale captured image data and the second low grayscale captured image data and the first high grayscale captured image data and the second high grayscale captured image data.

5. The display unevenness compensation device according to claim 1, wherein: The test image supplying section is configured to supply third image data to the display panel; and The test image capturing part is configured to capture a third image displayed on the display panel corresponding to the third image data, and to generate third captured image data by capturing the third image within a third reference exposure time, wherein the third reference exposure time is different from the first reference exposure time and the second reference exposure time.

6. The display unevenness compensation device according to claim 5, further comprising: A display unevenness compensation part is configured to generate first representative image data based on the first captured image data, generate second representative image data based on the second captured image data, generate third representative image data based on the third captured image data, and compensate for the display unevenness by using the first representative image data to the third representative image data.

7. The display unevenness compensation device according to claim 6, wherein: The first image data includes first to third low grayscale image data; The second image data includes first to third high grayscale image data; The third image data includes first to third medium grayscale image data; The first captured image data includes first to third low grayscale captured image data; The second captured image data includes first to third high grayscale captured image data; The third captured image data includes first to third mid-grayscale captured image data; and The display unevenness compensation part is configured as follows: calculating first to third low grayscale representative brightness code values ​​for the first to third low grayscale captured image data, respectively, and generating the first representative image data by using the calculated first to third low grayscale representative brightness values; calculating first to third high grayscale representative brightness code values ​​for the first to third high grayscale captured image data, respectively, and generating the second representative image data by using the calculated first to third high grayscale representative brightness values; as well as First to third mid-gray representative brightness code values ​​are calculated for the first to third mid-gray captured image data, respectively, and the third representative image data is generated by using the calculated first to third mid-gray representative brightness values.

8. The display unevenness compensation device according to claim 7, wherein: The first low-grayscale image data to the third low-grayscale image data are image data composed of different grayscales, the first medium-grayscale image data to the third medium-grayscale image data are image data composed of different grayscales, and the first high-grayscale image data to the third high-grayscale image data are image data composed of different grayscales.

9. The display unevenness compensation device according to claim 7, wherein: In a case where the first low-grayscale image data has a lower grayscale than the second low-grayscale image data and the third low-grayscale image data, and the second low-grayscale image data has a lower grayscale than the third low-grayscale image data, a grayscale difference between the second low-grayscale image data and the first low-grayscale image data is equal to a grayscale difference between the third low-grayscale image data and the second low-grayscale image data; In the case where the first medium-grayscale image data has a lower grayscale than the second medium-grayscale image data and the third medium-grayscale image data, and the second medium-grayscale image data has a lower grayscale than the third medium-grayscale image data, the grayscale difference between the second medium-grayscale image data and the first medium-grayscale image data is equal to the grayscale difference between the third medium-grayscale image data and the second medium-grayscale image data; and When the first high-grayscale image data has a lower grayscale than the second high-grayscale image data and the third high-grayscale image data, and the second high-grayscale image data has a lower grayscale than the third high-grayscale image data, the grayscale difference between the second high-grayscale image data and the first high-grayscale image data is equal to the grayscale difference between the third high-grayscale image data and the second high-grayscale image data.

10. The display unevenness compensation device according to claim 7, wherein: The grayscale difference between the second low grayscale image data and the first low grayscale image data is smaller than the grayscale difference between the second medium grayscale image data and the first medium grayscale image data and the grayscale difference between the second high grayscale image data and the first high grayscale image data; and A grayscale difference between the second medium-grayscale image data and the first medium-grayscale image data is smaller than a grayscale difference between the second high-grayscale image data and the first high-grayscale image data.

11. A method for compensating for uneven display, the method for compensating for uneven display being used to detect uneven display in an image displayed on a display panel and to compensate for the detected uneven display, the method for compensating for uneven display comprising the following steps: supplying image data to the display panel; Displaying an image by the display panel; generating captured image data by photographing the image; generating representative image data by using the captured image data; as well as By using the representative image data, the display unevenness is compensated, in, The image data includes first image data and second image data, and The images include a first image and a second image, and Among them, the step of generating the captured image data by shooting the image includes the following steps: generating first captured image data by shooting the first image within a first benchmark exposure time, and generating second captured image data by shooting the first image within a second benchmark exposure time, and the second benchmark exposure time is different from the first benchmark exposure time.

12. The display unevenness compensation method according to claim 11, wherein: The first image data includes first low-grayscale image data and second low-grayscale image data; The second image data includes first high grayscale image data and second high grayscale image data; The captured image data includes the first captured image data and the second captured image data; The first captured image data includes first low grayscale captured image data and second low grayscale captured image data; The second captured image data includes first high grayscale captured image data and second high grayscale captured image data; and The representative image data includes first representative image data and second representative image data; and Wherein, the step of generating the representative image data by using the captured image data includes the following steps: generating the first representative image data by using the first low-grayscale captured image data and the second low-grayscale captured image data, and generating the second representative image data by using the first high-grayscale captured image data and the second high-grayscale captured image data.

13. The display unevenness compensation method according to claim 11, wherein: The image data further includes third image data; The first image data includes first to third low grayscale image data; The second image data includes first to third high grayscale image data; The third image data includes first to third medium grayscale image data; The captured image data includes the first captured image data to the third captured image data; The first captured image data includes first to third low grayscale captured image data; The second captured image data includes first to third high grayscale captured image data; The third captured image data includes first to third mid-grayscale captured image data; and The representative image data includes first to third representative image data; and Among them, the step of generating the representative image data by using the captured image data includes the following steps: generating the first representative image data by using the first low-grayscale captured image data to the third low-grayscale captured image data, generating the second representative image data by using the first high-grayscale captured image data to the third high-grayscale captured image data, and generating the third representative image data by using the first medium-grayscale captured image data to the third medium-grayscale captured image data.

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