Display panel dark spot detection method and device and computer readable storage medium

Abstract

The invention discloses a dark spot detection method and device of a display panel and a computer readable storage medium. The dark spot detection method of the display panel comprises the following steps: step 401, acquiring first brightness of a plurality of sub-pixels at a first visual angle; 402, a first mapping relation between a first distance and a main light angle is obtained, the first distance is the distance between the sub-pixel and the center of the display area of the display panel, and the main light angle is the included angle between the direction, with the maximum luminous intensity, of the sub-pixel and the direction perpendicular to the display panel; step 403, acquiring the brightness of a single sub-pixel on multiple visual angles, and obtaining a second mapping relation between the visual angle of the single sub-pixel and the brightness; and step 404, according to the acquired first brightness, the first mapping relation and the second mapping relation, determining second brightness of the plurality of sub-pixels on the main light angle, and marking the sub-pixels with the second brightness lower than a brightness threshold as dark spots.

Description

Dark spot detection method and device for display panel, and computer-readable storage medium Technical Field

[0001] The embodiments of the present disclosure relate to, but are not limited to, the field of display panel detection technology, and in particular to a method and device for detecting dark spots in a display panel, and a computer-readable storage medium. Background Art

[0002] With the increasing advancement of augmented reality / virtual reality (VR / AR) technology and the rapid growth of the market, display panels suitable for VR / AR are also accelerating the development of miniaturization, high pixel density (PPI), fast response time, and high color gamut. Silicon-based organic light-emitting diode (OLED) microdisplay panels are a prominent trend in this field. Although silicon-based OLED microdisplay technology started later, it is becoming a new focus in the display field due to its advantages of miniaturization and high PPI.

[0003] During the production of silicon-based OLED microdisplays, pixel defects are an inevitable occurrence. To ensure the quality of display panels before shipment, sub-pixel dark spot testing is required.

[0004] Summary of the Invention

[0005] The following is a summary of the subject matter described in detail herein. This summary is not intended to limit the scope of the claims.

[0006] An embodiment of the present disclosure provides a method for detecting dark spots in a display panel, comprising:

[0007] Obtaining a first brightness of a plurality of sub-pixels at a first viewing angle;

[0008] Obtaining a first mapping relationship between a first distance and a primary light angle, where the first distance is the distance between the sub-pixel and the center of a display area of ​​the display panel, and the primary light angle is the angle between a direction of maximum luminous intensity of the sub-pixel and a direction perpendicular to the display panel;

[0009] Obtaining the brightness of a single sub-pixel at multiple viewing angles to obtain a second mapping relationship between the viewing angle and the brightness of the single sub-pixel;

[0010] The second brightness of the plurality of sub-pixels at the primary light angle is determined according to the acquired first brightness, the first mapping relationship, and the second mapping relationship, and sub-pixels whose second brightness is lower than a brightness threshold are marked as dark spots.

[0011] The present disclosure also provides a dark spot detection device for a display panel, comprising: a first acquisition module, a second acquisition module, a third acquisition module, and a first processing module, wherein:

[0012] The first acquisition module is configured to acquire a first brightness of a plurality of sub-pixels at a first viewing angle;

[0013] The second acquisition module is configured to acquire a first mapping relationship between a first distance and a principal light angle, where the first distance is the distance between the sub-pixel and the center of the display area of ​​the display panel, and the principal light angle is the angle between a direction of maximum luminous intensity of the sub-pixel and a direction perpendicular to a light emitting surface of the display panel;

[0014] The third acquisition module is configured to acquire the brightness of a single sub-pixel at multiple viewing angles to obtain a second mapping relationship between the viewing angle and the brightness of the single sub-pixel;

[0015] The first processing module is configured to determine the second brightness of the plurality of sub-pixels at the main light angle according to the acquired first brightness, the first mapping relationship and the second mapping relationship, and mark the sub-pixels whose second brightness is lower than the brightness threshold as dark spots.

[0016] An embodiment of the present disclosure also provides a dark spot detection device for a display panel, comprising a memory; and a processor connected to the memory, wherein the memory is used to store instructions, and the processor is configured to execute the steps of the dark spot detection method for a display panel described in any embodiment of the present disclosure based on the instructions stored in the memory.

[0017] An embodiment of the present disclosure further provides a computer-readable storage medium having a computer program stored thereon. When the program is executed by a processor, the dark spot detection method for a display panel described in any embodiment of the present disclosure is implemented.

[0018] Other aspects will become apparent upon reading and understanding the drawings and detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings are intended to provide a further understanding of the technical solutions of the present disclosure and constitute a part of the specification. Together with the embodiments of the present disclosure, they are used to explain the technical solutions of the present disclosure and do not constitute a limitation of the technical solutions of the present disclosure. The shapes and sizes of the components in the drawings do not reflect the actual scale and are intended only to illustrate the contents of the present disclosure.

[0020] FIG1 is a schematic diagram of a dark spot of a sub-pixel of a display panel;

[0021] FIG2 is a schematic diagram showing a curve of the principal light angle of an optical lens corresponding to a display panel and the principal light angle of a micro-lens of the display panel varying with a first distance;

[0022] FIG3 is a schematic diagram showing the brightness variation curves of several silicon-based OLED display panels as a function of temperature;

[0023] FIG4A is a schematic flow chart of a dark spot detection method for a display panel according to an exemplary embodiment of the present disclosure;

[0024] FIG4B is a schematic cross-sectional view of a display panel according to an exemplary embodiment of the present disclosure;

[0025] FIG4C is a top view of a display panel according to an exemplary embodiment of the present disclosure;

[0026] FIG4D is a schematic diagram showing the distribution of the main light angles of a display panel in the column direction according to an exemplary embodiment of the present disclosure;

[0027] FIG4E is a schematic diagram showing the distribution of the main light angles of a display panel in the row direction according to an exemplary embodiment of the present disclosure;

[0028] 5 and 6 are schematic diagrams of collecting first brightness information of a display panel according to an exemplary embodiment of the present disclosure;

[0029] FIG7 is a schematic diagram of brightness curves of a single sub-pixel of a display panel at different viewing angles according to an exemplary embodiment of the present disclosure;

[0030] FIG8 is a schematic diagram of sub-pixel sampling positions at different first distances according to an exemplary embodiment of the present disclosure;

[0031] 9A to 9D are schematic diagrams showing curves of sub-pixel brightness varying with viewing angle at different first distances in FIG. 8 obtained through testing;

[0032] FIG10 is a schematic structural diagram of a dark spot detection device for a display panel according to an exemplary embodiment of the present disclosure;

[0033] FIG11 is a schematic structural diagram of another dark spot detection device for a display panel according to an exemplary embodiment of the present disclosure;

[0034] FIG. 12 is a schematic structural diagram of another dark spot detection device for a display panel according to an exemplary embodiment of the present disclosure. DETAILED DESCRIPTION

[0035] To make the objectives, technical solutions and advantages of the present disclosure more clearly understood, the embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. It should be noted that, unless there is a conflict, the embodiments and features in the embodiments of the present disclosure can be combined with each other in any manner.

[0036] Unless otherwise defined, the technical or scientific terms used in the embodiments of the present disclosure should have the ordinary meaning understood by people with ordinary skills in the field to which the present disclosure belongs. The words "first", "second" and similar words used in the embodiments of the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. The words "include" or "comprising" and similar words mean that the elements or objects preceding the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0037] With the continuous development of display technology, silicon-based OLED display panels have attracted widespread attention due to their advantages such as high resolution, low power consumption, small size, and light weight. They have great application prospects in high-resolution near-eye display industries such as wearable devices, industrial security, and medical. To compensate for display defects (demura) in silicon-based OLED display panels, sub-pixel dark spots must be detected first.

[0038] Figure 1 is a schematic diagram of sub-pixel dark spots in a display panel. The white dots in Figure 1 are dark spots, and brighter white dots indicate lower brightness. Before performing demura compensation on these sub-pixel dark spots, the number and coordinates of these sub-pixel dark spots must be accurately detected.

[0039] Currently, the industry's methods for detecting dark spots on display panels include:

[0040] (1) Visual inspection: This method mainly relies on manual inspection. It cannot accurately output the number and coordinates of sub-pixel dark spots.

[0041] (2) Sub-pixel voltage or current information detection: It is impossible to detect sub-pixel dark spots caused by low efficiency of the light-emitting unit;

[0042] (3) Brightness detection of multiple sub-areas of the display panel: It is not applicable to dark spot detection of micro OLED display panels with chief ray angle (CRA), and the influence of temperature on sub-pixel brightness cannot be eliminated.

[0043] Near-eye display devices such as virtual reality devices and augmented reality devices may include a display panel and an optical lens. The optical lens is provided on the light-emitting side of the display panel (usually worn on the user's head for use) to adjust the light path of the display panel and form an image for the user to view within a specified space. The display panel may include multiple light-emitting devices and multiple microlenses. Each microlens is provided on the light-emitting side of the light-emitting device and is arranged one-to-one with each light-emitting device (or multiple light-emitting devices may correspond to one microlens). The microlens can converge the light emitted by the light-emitting device to a specified range to avoid excessive divergence of the light, thereby increasing the brightness of the display panel through the lens. Figure 2 is a schematic diagram of a curve showing the change of the main light angle of the optical lens corresponding to a display panel and the main light angle of the display panel microlens with the first distance, wherein the first distance refers to the distance from any point on the display panel to the center of the display area of ​​the display panel. As can be seen from Figure 2, as the first distance increases, the main light angle value of the optical lens and the main light angle value of the microlens gradually increase. However, the current display panel dark spot detection method is only applicable to the brightness collection of display panels without a main light angle.

[0044] Figure 3 shows a graph of the temperature-dependent brightness of several silicon-based OLED display panels. As shown in Figure 3, the brightness of silicon-based OLED display panels varies at different temperatures due to the varying luminous efficiency of their light-emitting units. Current methods for detecting dark spots in display panels cannot eliminate the impact of temperature on the brightness of silicon-based OLED display panels.

[0045] As shown in FIG4A , an embodiment of the present disclosure provides a method for detecting dark spots on a display panel. A plurality of microlens structures are provided on a light-emitting surface of the display panel. The method includes:

[0046] Step 401: Obtain a first brightness of a plurality of sub-pixels at a first viewing angle;

[0047] Step 402: Obtain a first mapping relationship between a first distance and a principal light angle, where the first distance is the distance between the sub-pixel and the center of the display area of ​​the display panel, and the principal light angle is the angle between a direction of maximum luminous intensity of the sub-pixel and a direction perpendicular to a light emitting surface of the display panel.

[0048] Step 403: Acquire the brightness of a single sub-pixel at multiple viewing angles to obtain a second mapping relationship between the viewing angle and brightness of the single sub-pixel;

[0049] Step 404: Determine the second brightness of the plurality of sub-pixels at the primary light angle according to the acquired first brightness, the first mapping relationship, and the second mapping relationship, and mark the sub-pixels whose second brightness is lower than the brightness threshold as dark spots.

[0050] The dark spot detection method for a display panel provided by the embodiment of the present disclosure determines the second brightness of multiple sub-pixels at the main light angle based on the first brightness of multiple sub-pixels at the first viewing angle, a first mapping relationship between the first distance and the main light angle, and a second mapping relationship between the viewing angle and brightness of a single sub-pixel. Sub-pixels whose second brightness is lower than the brightness threshold are marked as dark spots. The method can accurately output the number and coordinates of sub-pixel dark spots, ensure the accuracy of display panel dark spot detection, and significantly improve detection efficiency. In addition, the present disclosure is applicable to dark spot detection of display panels with a main light angle, can eliminate the influence of temperature on sub-pixel brightness, and can detect sub-pixel dark spots caused by various reasons, including low efficiency of the light-emitting unit.

[0051] As shown in FIG4B and FIG4C , the display panel of the present disclosure may include a driving backplane 1 and a plurality of light-emitting modules 01 , wherein: the driving backplane 1 has a pixel region 10 , and the pixel region 10 includes a central region 101 and n offset regions 102 sequentially surrounding the central region 101 ; n is a positive integer; the length of the pixel region 10 in the row direction is W; the length of the pixel region 10 in the column direction is L;

[0052] Multiple light-emitting modules 01 are provided on one side of the driver backplane 1 and are distributed in the central area 101 and the offset area 102. Each light-emitting module 01 includes multiple light-emitting units 011. Each light-emitting unit 011 includes a light-emitting device 0111 and a converging lens 0112 distributed in a direction away from the driver backplane 1.

[0053] In any light-emitting unit 011 within the offset region 102, the center of the orthographic projection of the light-emitting device 0111 on the driver backplane 1 is located on a side of the center of the orthographic projection of the converging lens 0112 on the driver backplane 1 that is away from the central region 101, and the distance between the center of the orthographic projection of the light-emitting device 0111 on the driver backplane 1 and the center of the orthographic projection of the converging lens 0112 on the driver backplane 1 is the offset of the light-emitting unit 011; the extension direction of the line between the center of the orthographic projection of the light-emitting device 0111 on the driver backplane 1 and the center of the orthographic projection of the converging lens 0112 on the driver backplane 1 is the offset direction of the light-emitting device 0111;

[0054] The light emitting units 011 in the same offset region 102 have the same offset amount; the light emitting units 011 in the same light emitting module 01 have the same offset direction;

[0055] The offset of the light-emitting unit 011 in the central area 101 is zero; the offset of the light-emitting unit 011 in any offset area 102 is greater than the offset of the light-emitting unit 011 in the central area 101, and the offset of the light-emitting unit 011 in each offset area 102 increases in the direction away from the central area 101.

[0056] The main light angles of the light-emitting units 011 in the same offset area 102 are the same, and the main light angles of the light-emitting units 011 in different offset areas 102 increase in the direction away from the central area 101, thereby increasing the light-emitting range of the display panel, so that the light-emitting range of the display panel matches the optical path component, and improving the uniformity of the brightness of the picture presented by the near-eye display device.

[0057] As shown in FIG4B and FIG4C , the driving backplane 1 of the display panel may further include a peripheral area 11. The peripheral area 11 is located outside the pixel area 10. The peripheral area 11 may be an annular area arranged around the pixel area 10. The driving backplane 1 is used to form a driving circuit for driving each light-emitting device 0111 to emit light. The driving circuit may include a pixel circuit and a peripheral circuit, wherein:

[0058] The number of pixel circuits and light-emitting devices 0111 can be multiple, and the pixel circuit is located in the pixel area 10. The pixel circuit can be a 2T1C, 4T2C, 6T1C or 7T1C pixel circuit. As long as it can drive the light-emitting device 0111 to emit light, its structure is not particularly limited here. The number of pixel circuits can be the same as the number of light-emitting devices 0111, and they are connected to the light-emitting devices 0111 in a one-to-one correspondence so as to control each light-emitting device 0111 to emit light. Among them, nTmC means that a pixel circuit includes n transistors (represented by the letter "T") and m capacitors (represented by the letter "C"). Of course, the same pixel circuit can also drive multiple light-emitting devices 0111.

[0059] The peripheral circuit is located in the peripheral area 11 and is connected to the pixel circuit. The peripheral circuit may include at least one of a light emitting control circuit, a gate drive circuit, a source drive circuit, and a power supply circuit. Of course, it may also include other circuits as long as it can drive the light emitting device 0111 to emit light through the pixel circuit.

[0060] In some embodiments of the present disclosure, the driving backplane 1 may include a substrate and at least one wiring layer provided on the substrate, wherein the substrate may be a silicon substrate, and the driving circuit may be formed on the silicon substrate by a semiconductor process. For example, both the pixel circuit and the peripheral circuit may include a plurality of transistors, and a well region may be formed in the silicon substrate by a doping process, and the well region has two doped regions spaced apart. At the same time, taking a well region as an example: a gate is provided on one side of the driving backplane 1, that is, the positive projection of the gate on the substrate is located between the two doped regions. At least one wiring layer is connected to the doped region, and a wiring layer may include a source and a drain of two doped regions connected to the same well region. By connecting the transistors through each wiring layer, a driving circuit can be formed. The specific connection lines and wiring patterns depend on the circuit structure and are not specifically limited here.

[0061] The routing layer may be covered with a flat layer, the material of which may be silicon oxide, silicon oxynitride or silicon nitride, which is formed layer by layer through multiple deposition and polishing processes. The flat layer may be formed by stacking multiple insulating film layers.

[0062] As shown in Figures 4B and 4C, a light-emitting functional layer 2 may be provided on the driving backplane 1. The light-emitting functional layer 2 may include a plurality of light-emitting devices 0111. Each light-emitting device 0111 is arrayed and distributed on one side of the driving backplane 1. For example, each light-emitting device 0111 is provided on the surface of the flat layer facing away from the substrate. Each light-emitting device 0111 may include a first electrode 21, a second electrode 24, and a light-emitting layer 23 located between the first electrode 21 and the second electrode 24. Both the first electrode 21 and the second electrode 24 may be connected to the wiring layer. At the same time, the peripheral circuit may also include a power supply circuit connected to the second electrode 24 for inputting a power supply signal to the second electrode 24. The peripheral circuit may input a driving signal to the first electrode 21 and a power supply signal to the second electrode 24 through the pixel circuit, thereby controlling the light-emitting device 0111 to emit light.

[0063] To achieve color display, each light-emitting device 0111 can emit light of the same color, and in conjunction with the color filter layer 4 located on the side of the second electrode 24 facing away from the substrate, color display can be achieved. The embodiments of this disclosure are described using this color display solution as an example. Of course, each light-emitting device can also emit light independently, and different light-emitting devices 0111 can emit light of different colors.

[0064] In some embodiments of the present disclosure, as shown in FIG4B , a plurality of light-emitting devices 0111 may be formed by a first electrode layer, a pixel definition layer 22 , a light-emitting layer 23 , and a second electrode 24 , wherein:

[0065] The first electrode layer is disposed on the surface of the planar layer facing away from the substrate. The first electrode layer may include a plurality of first electrodes 21 spaced apart from each other, and the orthographic projection of each first electrode 21 on the substrate is located in the pixel area 10 and connected to the pixel circuit, with one first electrode 21 connected to one pixel circuit.

[0066] As shown in FIG4B , the pixel definition layer 22 covers the planar layer and exposes each first electrode 21. Specifically, the pixel definition layer 22 has an opening 221 that exposes the first electrode 21. The pixel definition layer 22 and its opening 221 define the range of each light-emitting device 0111. The light-emitting range of the light-emitting device 0111 is also limited by the opening 221, and the boundary of the opening 221 is the boundary of the light-emitting device 0111. The direction of maximum light emission intensity of the light-emitting device 0111 can be a direction perpendicular to the first electrode 21 and passing through the center of the opening 221. The material of the pixel definition layer 22 can be an insulating material such as silicon oxide or silicon nitride, and is not particularly limited here.

[0067] As shown in FIG4B , the light-emitting layer 23 covers the pixel definition layer 22 and the first electrode 21. The region of the light-emitting layer 23 located within an opening 221 and overlapping the first electrode is used to form the light-emitting device 0111. In other words, each light-emitting device 0111 can share the same light-emitting layer 23. Specifically, the portions of the light-emitting layer 23 located within different openings 221 belong to different light-emitting devices 0111. Furthermore, because each light-emitting device 0111 shares the light-emitting layer 23, the light-emitting colors of the different light-emitting devices 0111 are the same.

[0068] For example, the light-emitting layer 23 may include multiple light-emitting sublayers sequentially connected in series along a direction away from the substrate, with at least one light-emitting sublayer connected in series with an adjacent light-emitting sublayer via a charge generation layer. When an electrical signal is applied to the first electrode 21 and the second electrode 24, each light-emitting sublayer can emit light, and different light-emitting sublayers can be used to emit light of different colors.

[0069] As shown in FIG4B , the second electrode 24 covers the light-emitting layer 23, and the orthographic projection of the second electrode 24 on the substrate can cover the pixel region 10 and extend into the peripheral region 11. Each light-emitting device 0111 can share the same second electrode 24. When the voltage difference between the second electrode 24 and the first electrode 21 reaches a voltage difference that can cause the light-emitting layer 23 to emit light, the light-emitting layer 23 can emit light. Therefore, the light emission of the light-emitting layer 23 can be controlled by controlling the voltage of the power signal input to the second electrode 24 and the drive signal input to the first electrode 21.

[0070] As shown in FIG4B , in some embodiments of the present disclosure, the display panel of the present disclosure may further include an encapsulation layer 3, which may cover each light-emitting device 0111. For example, the encapsulation layer 3 is provided on the side of the second electrode 24 facing away from the substrate, and is located between the color filter layer 4 and the second electrode 24, to block corrosion from external water and oxygen. The encapsulation layer 3 may be a single-layer or multi-layer structure. For example, the encapsulation layer 3 may include a first encapsulation sublayer 31, a second encapsulation sublayer 32, and a third encapsulation sublayer 33 stacked in sequence in a direction away from the substrate. The materials of the first encapsulation sublayer 31 and the second encapsulation sublayer 32 may be inorganic insulating materials such as silicon nitride (SiN) and aluminum oxide (Al2O3). For example, the material of the first encapsulation sublayer 31 is silicon nitride, and the material of the second encapsulation sublayer 32 is aluminum oxide; the material of the third encapsulation sublayer 33 may be an organic material such as parylene.

[0071] As shown in FIG4B , to achieve color display, the display panel may further include a color filter layer 4. This color filter layer 4 can be disposed on the side of the second electrode 24 facing away from the substrate and includes multiple filter sections 0113. Each light-emitting device 0111 is positioned opposite each filter section 0113 in a direction perpendicular to the substrate, such that the orthographic projection of a filter section 0113 on the flat layer at least partially overlaps with a first electrode 21. Each filter section 0113 includes at least three color filters 0113, for example, a filter section 0113 that transmits red light, a filter section 0113 that transmits green light, and a filter section 0113 that transmits blue light. Light emitted by each light-emitting device 0111 is filtered by the filter section 0113 to produce monochromatic light of different colors, thereby achieving color display.

[0072] The orthographic projection of the filter portion 0113 on the substrate may be larger than the opening 221 of the pixel definition layer 22 , and the orthographic projection of each opening 221 on the substrate is located within the orthographic projection of each filter portion 0113 on the substrate in a one-to-one correspondence.

[0073] As shown in FIG4B , the color filter layer 4 may further include a light-shielding portion separating the filter portion 0113. The light-shielding portion is opaque and blocks the area between the two light-emitting devices 0111. The filter portion 0113 may be directly formed of a light-shielding material and spaced apart from the filter portion 0113. Alternatively, in some embodiments of the present disclosure, adjacent filter portions 0113 may be stacked in the area corresponding to the area between two adjacent light-emitting devices 0111, with the two filter portions transmitting different colors of light, thereby rendering the stacked area opaque.

[0074] In addition, in some embodiments of the present disclosure, on the basis of the light-emitting layer 23 emitting white light, in order to improve the brightness of the picture, the color filter layer 4 may also include a transparent portion. In the direction perpendicular to the substrate, a transparent portion may be arranged opposite to a light-emitting unit 011, so that the color filter layer 4 can also transmit white light and increase the brightness through the white light.

[0075] A light-gathering layer can be provided on the side of the color filter layer 4 facing away from the driver backplane 1. This light-gathering layer comprises a plurality of convergent lenses 0112 arranged in an array. Each convergent lens 0112 is arranged in a one-to-one correspondence with each light-emitting device 0111 in a direction perpendicular to the driver backplane 1, and also corresponds to each filter 0113. Light emitted by any light-emitting device 0111 passes through its corresponding filter 0113 and convergent lens 0112. The convergent lens 0112 converges the light within a specified range, thereby increasing the brightness of the display panel.

[0076] As shown in FIG4B , the structure of the converging lens 0112 is not particularly limited, as long as it can achieve the above-mentioned converging function. For example, the converging lens 0112 can be a spherical segment structure protruding away from the driving back plate 1, and its surface can be surrounded by a plane and a spherical cap.

[0077] Based on the structure of the display panel described above, as shown in FIG4B , the display panel can be divided into multiple light-emitting modules 01. Each light-emitting module 01 is located on one side of the driver backplane 1 and may include multiple light-emitting units 011. Each light-emitting unit 011 may be arranged in an array along the row and column directions. Each light-emitting unit 011 may include a light-emitting device 0111 and its corresponding converging lens 0112, as well as a filter 0113 located between the light-emitting device 0111 and the converging lens 0112. The light-emitting range of the light-emitting unit 011 is defined by the light-emitting device 0111 and the converging lens 0112, and the color of the light emitted by the light-emitting unit 011 is defined by the filter 0113. A light-emitting module 01 can be considered a pixel, and each light-emitting unit 011 contained therein can be considered a sub-pixel.

[0078] In some embodiments of the present disclosure, one light emitting module 01 may include three light emitting units 011 emitting light of different colors, for example, a red light emitting unit 011 , a green light emitting unit 011 , and a blue light emitting unit 011 .

[0079] As shown in Figure 4B, in any light-emitting unit 011, the distance between the center of the orthographic projection of the light-emitting device 0111 on the driving backplane 1 and the center of the orthographic projection of its converging lens 0112 on the driving backplane 1 can be defined as the offset △S of the light-emitting unit 011; the extension direction of the line between the center of the orthographic projection of the light-emitting device 0111 on the driving backplane 1 and the center of the orthographic projection of the converging lens 0112 on the driving backplane 1 is the offset direction of the light-emitting device 0111; as shown in Figures 4D and 4E, the angle between the direction in which the luminous intensity of the light-emitting unit 011 is the maximum and the direction perpendicular to the driving backplane 1 is the principal light angle.

[0080] As shown in Figures 4D and 4E, the light-emitting range of any light-emitting unit 011 is the main light angle ± the specified angle γ. For example, the specified angle γ can be 15°. Of course, the specified angle can also be 20° or 10°, etc., depending on the light-emitting range of the light-emitting device 0111 and the size of the filter part 0113 and the converging lens 0112. No special limitation is made here.

[0081] The offset amounts of the light-emitting units 011 within the same offset area 102 are the same, so that the main light angles of the light-emitting units 011 within the same offset area 102 are the same, but the offset directions can be distributed radially along the circumference around the central area 101; the offset directions of the light-emitting units 011 of the same light-emitting module 01 are the same, avoiding the influence of different main light angles of the light-emitting units 011 of the same light-emitting module 01 on the picture display.

[0082] As shown in Figures 4B to 4E , the offset of the light-emitting unit 011 in the central area 101 is zero, that is, the primary light angle of the light-emitting unit 011 in the central area 101 is zero, and the direction of its maximum brightness is perpendicular to the driver backplane 1. The offset of the light-emitting unit 011 in any offset area 102 is greater than the offset of the light-emitting unit 011 in the central area 101, and the offset of the light-emitting unit 011 in different offset areas 102 increases in the direction away from the central area 101, so that the primary light angle increases in the direction away from the central area 101, thereby increasing the light-emitting range.

[0083] Because each offset region 102 corresponds to a different primary light angle, conventional dark spot detection methods are unable to effectively identify dark spots. The dark spot detection method of the disclosed embodiment determines the second brightness of multiple sub-pixels at the primary light angle based on the first brightness of the multiple sub-pixels at the first viewing angle, a first mapping relationship between the first distance and the primary light angle, and a second mapping relationship between the viewing angle and brightness of a single sub-pixel. Sub-pixels whose second brightness is below a brightness threshold are marked as dark spots. This method accurately outputs the number and coordinates of sub-pixel dark spots, ensuring the accuracy of display panel dark spot detection and significantly improving detection efficiency.

[0084] In some exemplary embodiments, the display panel includes a plurality of first sub-pixels emitting a first color light, a plurality of second sub-pixels emitting a second color light, and a plurality of third sub-pixels emitting a third color light, and obtaining a first brightness of the plurality of sub-pixels at a first viewing angle includes:

[0085] causing the display panel to display a pure color image of the first color;

[0086] The first brightness of all first sub-pixels at the first viewing angle is tested on the entire surface at one time using a first testing device.

[0087] In some exemplary embodiments, obtaining a first brightness of a plurality of sub-pixels at a first viewing angle further includes:

[0088] causing the display panel to display a pure color picture of the second color;

[0089] The first brightness of all second sub-pixels at the first viewing angle is tested on the entire surface at one time using the first testing device.

[0090] In some exemplary embodiments, obtaining a first brightness of a plurality of sub-pixels at a first viewing angle further includes:

[0091] causing the display panel to display a pure color picture of the third color;

[0092] The first brightness of all third sub-pixels at the first viewing angle is tested on the entire surface at one time using the first testing device.

[0093] The dark spot detection method of the embodiment of the present disclosure performs detection on each color sub-pixel separately. During each detection, the display panel displays a monochrome image P. For example, the monochrome image P can be an R255 image, a G255 image, or a B255 image. The first test device is used to test the first brightness information L of all luminous sub-pixels (first sub-pixel, second sub-pixel, or third sub-pixel) at the first viewing angle on the entire surface at one time. 0(i,j) , with the center of the display area of ​​the display panel as the coordinate origin, i and j are the X-axis coordinates and Y-axis coordinates of the sub-pixel respectively, -n1≤i≤n2, -m1≤j≤m2, n1+n2+1 is the number of sub-pixel columns, m1+m2+1 is the number of sub-pixel rows, and n1, n2, m1 and m2 are all natural numbers greater than or equal to 1.

[0094] In some exemplary embodiments, the first color, the second color, and the third color may be any one of red, green, and blue, respectively. However, the present disclosure is not limited thereto, and the display panel may include four or other numbers of sub-pixels of different colors. For example, the display panel may include a plurality of red sub-pixels emitting red light, a plurality of green sub-pixels emitting green light, a plurality of blue sub-pixels emitting blue light, and a plurality of white sub-pixels emitting white light.

[0095] In some exemplary embodiments, the first viewing angle may be a 0° viewing angle, but the present disclosure is not limited thereto.

[0096] In the embodiment of the present disclosure, when the line connecting the light emitted from the sub-pixel to the human eye or the test device is perpendicular to the light-emitting surface of the display panel, the viewing angle of the human eye or the test device is 0°; when the line connecting the light emitted from the sub-pixel to the human eye or the test device is not perpendicular to the light-emitting surface of the display panel, the viewing angle of the human eye or the test device is between (0°, 90°) or (-90°, 0°), for example, it may be a 10° viewing angle.

[0097] In some exemplary embodiments, the first testing device may be an area imaging luminance meter or an image-type luminance meter.

[0098] Brightness refers to the brightness of light perceived by the eyes when a person sees a light source. The symbol for brightness is L, and the unit is nit, where 1nit = 1 candela / m 2 (cd / m 2 ), where cd is the unit of light intensity. Area imaging luminance meters use an array of charge-coupled devices (CCDs) as light detectors. They can simultaneously measure the brightness of millions of points on a plane with just a single sampling, equivalent to millions of point luminance meters operating simultaneously.

[0099] In some exemplary embodiments, the first test device satisfies the following measurement conditions: 0.01 <k1a×Nx / f<0.1; 0.01<k2b×Ny / f<0.1; k1=nx / Nx;k2=ny / Ny;

[0100] Wherein, a is the length of the light-emitting unit in the sub-pixel along the first direction X, b is the length of the light-emitting unit in the sub-pixel along the second direction Y, Nx is the number of light-emitting units of the display panel along the first direction X, Ny is the number of light-emitting units of the display panel along the second direction Y, f is the focal length of the lens of the first test device, nx is the number of light-emitting units within the effective sampling diameter range of the first test device in a plane perpendicular to the plane where the display panel is located, passing through the center line of the first test device, and parallel to the first direction X; ny is the number of light-emitting units within the effective sampling diameter range of the first test device in a plane perpendicular to the plane where the display panel is located, passing through the center line of the first test device, and parallel to the second direction Y.

[0101] As shown in Figure 3, because the temperature of the display panel affects the display brightness, the brightness information collected at different times may vary depending on the temperature. When the first test device meets the above measurement conditions, the first test device can collect the entire display panel in a single acquisition, thereby eliminating the impact of display panel temperature changes on the test results.

[0102] Figures 5 and 6 are schematic diagrams of collecting first brightness information of a display panel according to an exemplary embodiment of the present disclosure. As shown in Figures 5 and 6, the first test device 20 can be located on the light-emitting side of the display panel (exemplarily, it can be located in the center of the light-emitting side in front of the display panel) to collect brightness information of the display panel. The display area of ​​the display panel may include multiple sub-pixels, each of which includes a light-emitting unit 011. The light-emitting unit 011 can be, for example, rectangular, however, this is not limited in the present embodiment. The length of the light-emitting unit 011 along the first direction X can be a, and the length along the second direction Y can be b. The number of light-emitting units 011 in the display area of ​​the display panel along the first direction X can be Nx, and the number of light-emitting units 011 along the second direction Y can be Ny. For example, the attribute information of the light-emitting units 011 of the display panel may include at least: the length a of the light-emitting unit 011 along the first direction X, the length b along the second direction Y, the number Nx of light-emitting units in the display area along the first direction X, and the number Ny of light-emitting units in the display area along the second direction Y.

[0103] As shown in Figure 6, taking an area imaging luminance meter as an example, assume that the focal length of the lens of the area imaging luminance meter is f. Within a plane perpendicular to the plane of the display panel and passing through the centerline of the area imaging luminance meter, the effective sampling diameter of the area imaging luminance meter can be L. Within a plane perpendicular to the plane of the display panel, passing through the centerline of the area imaging luminance meter, and parallel to the first direction X, the number of light-emitting units within the effective sampling diameter can be nx. Within a plane perpendicular to the plane of the display panel, passing through the centerline of the area imaging luminance meter, and parallel to the second direction Y, the number of light-emitting units within the effective sampling diameter can be ny. The sampling angle of the area imaging luminance meter can be θ. In this embodiment, the sampling angle is defined as the angle between the sampling edge line of sight and the centerline of the test device. In this example, the acquisition parameters of the first test device 20 may include at least: lens focal length f, sampling angle θ, and effective sampling diameter L.

[0104] The first test device 20 meets the following one-time whole-surface acquisition conditions for the display panel: 0.01 <k1a×Nx / f<0.1; 0.01<k2b×Ny / f<0.1;

[0105] Where k1 = nx / Nx; k2 = ny / Ny. 0 < k1 ≤ 1, 0 < k2 ≤ 1. For example, k1 and k2 can be greater than 0.3. When the first test device 20 meets the conditions for a one-time, full-surface acquisition of the display panel to be tested, the first test device 20 can eliminate the impact of temperature on the brightness values ​​of all light-emitting units of the display panel and perform brightness acquisition. In this way, using the acquired first brightness information to perform dark spot detection on the display panel helps improve the accuracy and efficiency of the test and evaluation results.

[0106] In some other exemplary embodiments, the one-time whole-surface acquisition conditions may further include:

[0107] The sampling viewing angle θ of the first test device is greater than or equal to A degrees, where A is between 7 and 10.

[0108] In this example, when the conditions for simultaneous full-surface acquisition are met, the first test device 20 can simultaneously eliminate the effects of viewing angle and temperature on the display panel's luminance values ​​during luminance acquisition, thereby improving the accuracy and efficiency of the test and evaluation results. When the sub-pixel under test is within the sampling viewing angle θ of the area imaging luminance meter, the area imaging luminance meter converts the luminance at the actual viewing angle to the luminance at a viewing angle of 0°, regardless of whether the actual viewing angle of the sub-pixel under test is 0°.

[0109] Table 1 provides examples of attribute information and acquisition parameters of light-emitting units of various types of display panels. As shown in Table 1, display panel 1 is a small-size display panel (e.g., 0.39 inches, with a resolution of 1920×1080), display panel 2 is a large-size display panel (e.g., 6.0 inches, with a resolution of 2560×1600), display panel 3 is a large-size display panel (e.g., 6.0 inches, with a resolution of 1280×720), display panel 4 is a large-size display panel (e.g., 5.0 inches, with a resolution of 1920×1080), display panel 5 is a large-size display panel (e.g., 7.0 inches, with a resolution of 1024×600), and display panel 6 is a large-size display panel (e.g., 9.7 inches, with a resolution of 2048×1536).

[0110] Table 1

[0111] As can be seen from Table 1, display panel one is a small-size display panel (such as a silicon-based OLED), and display panels two to six are all large-size display panels (such as a glass-based OLED or a PI-based OLED). For small-size display panels, when the one-time whole-surface acquisition condition is met (due to the small size, the one-time whole-surface acquisition condition can usually be met), the first test device can be used to acquire the brightness values ​​of all the light-emitting units of the display panel in a single whole-surface acquisition, thereby eliminating the influence of temperature on the dark spot detection results of the display panel. For large-size display panels, since the first test device only acquires the brightness values ​​of the light-emitting units in a part of the display area of ​​the display panel at a single time, the brightness values ​​of the light-emitting units outside the acquisition range will be distorted, and multiple acquisitions are required to achieve whole-surface acquisition. During the multiple acquisitions, the influence of temperature on the brightness detection results cannot be eliminated.

[0112] In some exemplary embodiments, obtaining a first mapping relationship between a first distance and a main light angle includes:

[0113] Testing, by a second testing device, the primary light angles of sub-pixels at N1 different first distances, where N1 is a natural number greater than 2;

[0114] A first mapping relationship between the first distance and the main light angle is obtained through formula fitting.

[0115] In the disclosed embodiment, after obtaining N1 sets of mapping data between the first distance and the primary light angle using a second testing device, a formula fitting can be performed using software such as Matlab or Excel to obtain a first mapping relationship between the first distance and the primary light angle. Subsequently, the primary light angle corresponding to a sub-pixel at any first distance can be obtained based on this first mapping relationship. When obtaining the first mapping relationship between the first distance and the primary light angle, these N1 test points must cover at least the center pixel of the display area and the pixels at the extreme edge of the display area to ensure statistical significance.

[0116] In some exemplary embodiments, when a formula fitting is performed on the first mapping relationship between the first distance and the main light angle, a curve corresponding to the first mapping relationship between two adjacent first distances is a straight line.

[0117] For example, if two adjacent first distances and principal light angle data are (d1, CRA1) and (d2, CRA2), respectively, then the slope of the straight line fitted between the two first distances is: (CRA2-CRA1) / (d2-d1). In this way, a curve composed of multiple straight line segments is fitted from the coordinate origin (i.e., the center of the display area of ​​the display panel) to the edge of the display panel, as shown in Figure 2, where the first mapping relationship curve corresponding to the principal light angle of the microlens is set as a straight line between two adjacent sampling points.

[0118] In some exemplary embodiments, the second testing device may be a spot luminance meter.

[0119] In some exemplary embodiments, N1 sub-pixels are arranged at equal distances. For example, the main light angle corresponding to a sub-pixel may be tested every 0.5 mm or 1 mm.

[0120] In step 402, a point luminance meter is used to test the main light angle CRA at different first distances when the display panel displays a monochrome image P. (i,j) The test results are shown in the microlens principal angle curve in Figure 2. The first distance H at the sub-pixel (i, j) (i,j) The calculation expression and the first distance H obtained by fitting (i,j) CRA of the chief ray angle at (i,j) The expressions are: CRA (i,j) =-0.0004H (i,j) 6 +0.007H (i,j) 5 -0.0175H (i,j) 4 -0.1632H (i,j) 3 + 0.6798H (i,j) 2+1.4375H (i,j) +0.0082 (2)

[0121] In formulas (1) and (2), the center of the display area of ​​the display panel is the coordinate origin, i and j are the coordinates of the sub-pixel, a and b are the length and width of the sub-pixel, -n1≤i≤n2, -m1≤j≤m2, n1+n2+1 is the number of sub-pixel columns, m1+m2+1 is the number of sub-pixel rows, and n1, n2, m1, and m2 are all natural numbers greater than or equal to 1. In the embodiments of the present disclosure, the above-mentioned fitted formula (2) is only an example, and the fitted formula (2) obtained for different display panels may be different.

[0122] In some exemplary embodiments, obtaining the brightness of a single sub-pixel at multiple viewing angles to obtain a second mapping relationship between the viewing angle and the brightness of the single sub-pixel includes:

[0123] Testing, using a second testing device, the luminance value of a single sub-pixel at N2 different viewing angles, where N2 is a natural number greater than 2, a maximum viewing angle among the N2 different viewing angles being greater than or equal to θ1°, and a minimum viewing angle being less than or equal to -θ2°, where θ1 is equal to a maximum primary ray angle value among the primary ray angles of all the sub-pixels, and -θ2 is equal to a minimum primary ray angle value among the primary ray angles of all the sub-pixels;

[0124] By formula fitting, a second mapping formula between viewing angle and brightness of a single sub-pixel is obtained.

[0125] In the embodiment of the present disclosure, N2 different viewing angles must satisfy a certain test viewing angle range, i.e., (-θ2°, θ1°), in order to achieve a better curve / formula fitting effect. In actual use, the value range of θ1 and θ2 can be determined based on the maximum and minimum main light angles of all sub-pixels of the display panel. For example, assuming that the maximum and minimum main light angles are 40° and -40°, respectively, θ1 can take a value greater than or equal to 40, and -θ2 can take a value less than or equal to 40, thereby ensuring the validity of the fitting curve / formula.

[0126] In some exemplary embodiments, a single sub-pixel (i0, j0) may be located at the center of the display area.

[0127] In this example, when a point luminance meter is used to test the display panel displaying a monochrome image P, the brightness value of a single sub-pixel at different viewing angles is -n1≤i0≤n2, -m1≤j0≤m2. For example, i0=0, j0=0. In this way, the accuracy of dark spot detection of the display panel can be ensured.

[0128] In this embodiment, the curve corresponding to the second mapping relationship between the viewing angle θ and the brightness L of a single sub-pixel is about the main light angle Symmetrical curves Among them, -90°≤θ≤90°, The brightness curve satisfies: L takes the derivative of θ, The derivative at is equal to 0, that is

[0129] For example, FIG7 is a schematic diagram of the brightness curve of a single sub-pixel (i0, j0) of a display panel under different viewing angles according to an exemplary embodiment of the present disclosure. In FIG7, the plane where the viewing angle direction is located is a plane passing through the center of the display area of ​​the display panel and the sub-pixel (i0, j0) point, and perpendicular to the light-emitting surface of the display panel. As shown in FIG7, the brightness calculation expression of a single sub-pixel (i0, j0) obtained by fitting is as follows: LV α =-1E-07α 6 +6E-06α 5 +0.0009α 4 -0.025α 3 -2.1026α 2 + 26.112α+1897.3 (3)

[0130] Where α is the viewing angle at the half-image height of a single sub-pixel (i0, j0); LV α is the luminance value of a single sub-pixel (i0, j0) at the half-image height α, where α is between -90° and 90°. In the disclosed embodiment, the above-mentioned fitted formula (3) is only an example, and the fitted formula (3) for different display panels may be different.

[0131] In some exemplary embodiments, determining the second brightness of the plurality of sub-pixels at the main light angle according to the acquired first brightness, the first mapping relationship, and the second mapping relationship includes:

[0132] Determine the sub-pixel (i0, j0) at the main light angle Brightness on

[0133] For multiple sub-pixels (i, j), perform the following operations respectively:

[0134] Determine the main light angle CRA of the sub-pixel (i, j) according to the first mapping relationship (i,j) , calculate the difference in main light angle according to the second mapping relationship Corresponding brightness

[0135] The brightness of sub-pixel (i, j) at 0° viewing angle Sub-pixel (i0, j0) at the main light angle Brightness on and the difference in the main light angle Corresponding brightness Substitute the following calculation formula: Get the sub-pixel (i, j) at the main light angle CRA (i,j) Second brightness on

[0136] Among them, -n1≤i≤n2, -m1≤j≤m2, n1+n2+1 is the number of sub-pixel columns, m1+m2+1 is the number of sub-pixel rows, and n1, n2, m1 and m2 are all natural numbers greater than or equal to 1.

[0137] In some other exemplary embodiments, determining the second brightness of the plurality of sub-pixels at the main light angle according to the acquired first brightness, the first mapping relationship, and the second mapping relationship includes:

[0138] For multiple sub-pixels (i, j), perform the following operations respectively:

[0139] Determine the main light angle CRA of the sub-pixel (i, j) according to the first mapping relationship (i,j) ,

[0140] According to the brightness of sub-pixel (i, j) at 0° viewing angle The main light angle CRA of sub-pixel (i, j) (i,j) And the second mapping relationship between the viewing angle and brightness of a single sub-pixel (i0, j0) is obtained, and the third mapping relationship between the viewing angle and brightness at the sub-pixel (i, j) is obtained. The curve corresponding to the third mapping relationship is about the main light angle CRA (i,j) Symmetrical curves;

[0141] According to the third mapping relationship, the sub-pixel (i, j) at the main light angle CRA is obtained. (i,j) The second brightness on.

[0142] Figure 8 is a schematic diagram of sub-pixel sampling locations at different first distances according to an exemplary embodiment of the present disclosure. As shown in Figure 8, a total of 41 sub-pixel sampling points are set, located on axes 1# to 4#, and the first distances of multiple sub-pixels on each concentric circle are the same, where R2 represents a first distance of 2 mm, and the meanings of R4 to R12 are similar. Figures 9A to 9D are schematic diagrams of the sub-pixel brightness variation with viewing angle at different first distances in Figure 8 obtained through testing. As shown in Figures 9A to 9D, the brightness curves of sub-pixels at different first distances as a function of viewing angle are essentially consistent.

[0143] Therefore, the embodiment of the present disclosure proposes a CRA brightness viewing angle full-screen panning test method that can greatly improve the detection efficiency, that is, according to the first brightness information of the sub-pixel (i, j) (0° viewing angle ), sub-pixel (i0, j0) at the main light angle Brightness on and the difference in the main light angle Corresponding brightness Calculate the brightness value of different sub-pixels (i, j) at the main light angle The brightness value of different sub-pixels (i, j) at the main light angle can be calculated This greatly speeds up the detection efficiency.

[0144] In some exemplary embodiments, the brightness threshold may include any one of the following: a preset brightness value, an average brightness value of some sub-pixels in the first display area, or an average brightness value of all sub-pixels in the first display area, where the first display area may be the entire display screen or a portion of the entire display screen.

[0145] For example, the display panel can be divided into multiple display sub-areas, and dark spot detection can be performed on each of the multiple display sub-areas. At this time, the brightness threshold can be set to any one of the following: the average brightness of all red sub-pixels (or green sub-pixels or blue sub-pixels) in a single display sub-area, or the average brightness of all sub-pixels in a single display sub-area.

[0146] For example, after obtaining the second brightness of the plurality of sub-pixels at the main light angle, the average brightness of the plurality of sub-pixels at the main light angle is calculated. Set the second brightness to be lower than the average brightness The sub-pixels are marked as dark spots, and finally the number and coordinate positions of the sub-pixel dark spots of the display panel are counted and output.

[0147] The dark spot detection method provided by the embodiment of the present disclosure eliminates the influence of temperature on sub-pixel brightness through a one-time whole-surface test; ensures the accuracy of dark spot detection of the display panel through single-point brightness viewing angle testing at a single sub-pixel; and greatly improves detection efficiency through the CRA brightness viewing angle full-screen translation test method.

[0148] As shown in FIG10 , an embodiment of the present disclosure further provides a dark spot detection device for a display panel, comprising: a first acquisition module 1001 , a second acquisition module 1002 , a third acquisition module 1003 , and a first processing module 1004 , wherein:

[0149] A first acquisition module 1001 is configured to acquire a first brightness of a plurality of sub-pixels at a first viewing angle;

[0150] A second acquisition module 1002 is configured to acquire a first mapping relationship between a first distance and a principal light angle, where the first distance is the distance between the sub-pixel and the center of the display area of ​​the display panel, and the principal light angle is the angle between a direction of maximum luminous intensity of the sub-pixel and a direction perpendicular to a light emitting surface of the display panel;

[0151] The third acquisition module 1003 is configured to acquire the brightness of a single sub-pixel at multiple viewing angles to obtain a second mapping relationship between the viewing angle and the brightness of the single sub-pixel;

[0152] The first processing module 1004 is configured to determine the second brightness of the plurality of sub-pixels at the primary light angle according to the acquired first brightness, the first mapping relationship, and the second mapping relationship, and mark the sub-pixels whose second brightness is lower than the brightness threshold as dark spots.

[0153] In some exemplary embodiments, the first viewing angle is a 0° viewing angle.

[0154] In some exemplary embodiments, the second acquisition module 1002 acquires a first mapping relationship between the first distance and the main light angle, including:

[0155] Obtaining primary light angles of sub-pixels at N1 different first distances obtained by testing with a second testing device, where N1 is a natural number greater than 2;

[0156] A first mapping relationship between the first distance and the main light angle is obtained through formula fitting.

[0157] In some exemplary embodiments, when a formula fitting is performed on the first mapping relationship between the first distance and the main light angle, a curve corresponding to the first mapping relationship between two adjacent first distances is a straight line.

[0158] In some exemplary embodiments, the third acquisition module 1003 acquires the brightness of a single sub-pixel at multiple viewing angles to obtain a second mapping relationship between the viewing angle and the brightness of the single sub-pixel, including:

[0159] Obtaining luminance values ​​of a single sub-pixel at N2 different viewing angles obtained by testing with a second testing device, where N2 is a natural number greater than 2, a maximum viewing angle among the N2 different viewing angles is greater than or equal to θ1°, and a minimum viewing angle is less than or equal to -θ2°, where θ1 is equal to a maximum primary ray angle value among the primary ray angles of all sub-pixels, and -θ2 is equal to a minimum primary ray angle value among the primary ray angles of all sub-pixels;

[0160] By fitting the formula, a second mapping relationship between the viewing angle and the brightness of a single sub-pixel is obtained.

[0161] In this embodiment, the curve corresponding to the second mapping relationship between the viewing angle θ and the brightness L of a single sub-pixel is a curve about the symmetrical viewing angle. Symmetrical curves Among them, -90°≤θ≤90°, The brightness curve satisfies: L takes the derivative of θ, The derivative at is equal to 0, that is

[0162] In some exemplary embodiments, the first processing module 1003 determines the second brightness of the plurality of sub-pixels at the main light angle according to the acquired first brightness, the first mapping relationship, and the second mapping relationship, including:

[0163] Determine the sub-pixel (i0, j0) at the main light angle Brightness on

[0164] For multiple sub-pixels (i, j), perform the following operations respectively:

[0165] Determine the main light angle CRA of the sub-pixel (i, j) according to the first mapping relationship (i,j) , calculate the difference in main light angle according to the second mapping relationship Corresponding brightness

[0166] The brightness of sub-pixel (i, j) at 0° viewing angle Sub-pixel (i0, j0) at the main light angle Brightness on and the difference in the main light angle Corresponding brightness Substitute the following calculation formula: Get the sub-pixel (i, j) at the main light angle CRA (i,j) Second brightness on

[0167] Among them, -n1≤i≤n2, -m1≤j≤m2, n1+n2+1 is the number of sub-pixel columns, m1+m2+1 is the number of sub-pixel rows, and n1, n2, m1 and m2 are all natural numbers greater than or equal to 1.

[0168] The dark spot detection method of the embodiment of the present disclosure is calculated by the formula: Calculating the second brightness of multiple sub-pixels at the main light angle can not only improve the detection efficiency, but also eliminate the brightness difference caused by process deviation.

[0169] In some other exemplary embodiments, the first processing module 1003 determines the second brightness of the plurality of sub-pixels at the main light angle according to the acquired first brightness, the first mapping relationship, and the second mapping relationship, including:

[0170] For multiple sub-pixels (i, j), perform the following operations respectively:

[0171] Determine the main light angle CRA of the sub-pixel (i, j) according to the first mapping relationship (i,j) ,

[0172] According to the brightness of sub-pixel (i, j) at 0° viewing angle The main light angle CRA of sub-pixel (i, j) (i,j) And the second mapping relationship between the viewing angle and brightness of a single sub-pixel (i0, j0) is obtained, and the third mapping relationship between the viewing angle and brightness at the sub-pixel (i, j) is obtained. The curve corresponding to the third mapping relationship is about the main light angle CRA (i,j) Symmetrical curves;

[0173] According to the third mapping relationship, the sub-pixel (i, j) at the main light angle CRA is obtained. (i,j) The second brightness on.

[0174] In some exemplary embodiments, the dark spot detection device further includes a second processing module 1005, wherein:

[0175] The second processing module 1005 is configured to determine whether the one-time full-surface acquisition condition is met based on the attribute information of the light-emitting unit in the display area of ​​the display panel and the acquisition parameters of the first test device, and the first test device is used to obtain the first brightness of multiple sub-pixels at the first viewing angle.

[0176] FIG11 is a schematic diagram of another dark spot detection device for a display panel according to an embodiment of the present disclosure. As shown in FIG11 , the dark spot detection device further includes: a second processing module 1005, wherein the second processing module 1005 determines whether the one-time whole-surface acquisition condition is met based on the attribute information of the light-emitting unit of the display area of ​​the display panel to be detected and the acquisition parameters of the first test device. Generally speaking, silicon-based OLED display panels can generally meet the one-time whole-surface acquisition condition due to their small size. When using the dark spot detection method of the present disclosure to test non-silicon-based OLED display panels, such as glass-based OLED or PI-based OLED display panels, it can be determined whether the one-time whole-surface acquisition condition is met based on the processing results of the second processing module 1005 to determine whether the detection results can exclude the influence of temperature on the brightness of the display panel.

[0177] For other explanations about the dark spot detection device of this embodiment, reference can be made to the description of the aforementioned embodiment, which will not be repeated here.

[0178] An embodiment of the present disclosure also provides a dark spot detection device for a display panel, comprising a memory; and a processor connected to the memory, wherein the memory is used to store instructions, and the processor is configured to execute the steps of the dark spot detection method for a display panel as described in any embodiment of the present disclosure based on the instructions stored in the memory.

[0179] As shown in FIG12 , in one example, a dark spot detection apparatus for a display panel may include: a processor 1210, a memory 1220, and a bus system 1230, wherein the processor 1210 and the memory 1220 are connected via the bus system 1230, the memory 1220 is configured to store instructions, and the processor 1210 is configured to execute the instructions stored in the memory 1220. Specifically, the processor 1210 obtains first brightness of multiple sub-pixels at a first viewing angle, obtains a first mapping relationship between a first distance and a primary light angle, wherein the first distance is the distance between the sub-pixel and the center of the display area of ​​the display panel, and the primary light angle is the angle between a direction of maximum luminous intensity of the sub-pixel and a direction perpendicular to a light emitting surface of the display panel, obtains brightness of a single sub-pixel at multiple viewing angles, obtains a second mapping relationship between viewing angle and brightness of the single sub-pixel, determines a second brightness of the multiple sub-pixels at the primary light angle based on the obtained first brightness, the first mapping relationship, and the second mapping relationship, and marks sub-pixels whose second brightness is lower than a brightness threshold as dark spots.

[0180] It should be understood that the processor 1210 may be a central processing unit (CPU), or may be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor.

[0181] The memory 1220 may include a read-only memory and a random access memory, and provides instructions and data to the processor 1210. A portion of the memory 1220 may also include a non-volatile random access memory. For example, the memory 1220 may also store information about the device type.

[0182] In addition to the data bus, the bus system 1230 may also include a power bus, a control bus, a status signal bus, etc. However, for the sake of clarity, various buses are labeled as the bus system 1230 in FIG.

[0183] During implementation, the processing performed by the processing device can be completed by the hardware integrated logic circuit in the processor 1210 or by instructions in the form of software. That is, the method steps of the embodiment of the present disclosure can be embodied as being executed by a hardware processor, or being executed by a combination of hardware and software modules in the processor. The software module can be located in a storage medium such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in the memory 1220, and the processor 1210 reads the information in the memory 1220 and completes the steps of the above method in combination with its hardware. To avoid repetition, it will not be described in detail here.

[0184] The present disclosure also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the display panel dark spot detection method described in any of the embodiments of the present disclosure. The method for driving dark spot detection on a display panel by executing the executable instructions is substantially the same as the display panel dark spot detection method provided in the aforementioned embodiments of the present disclosure and is not further described here.

[0185] In some possible embodiments, various aspects of the dark spot detection method for a display panel provided by the present disclosure may also be implemented in the form of a program product, which includes program code. When the program product is run on a computer device, the program code is used to enable the computer device to execute the steps of the dark spot detection method for a display panel according to various exemplary embodiments of the present disclosure described above in this specification. For example, the computer device may execute the dark spot detection method for a display panel recorded in the embodiments of the present disclosure.

[0186] The program product may employ any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. The readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or component, or any combination thereof. More specific examples (a non-exhaustive list) of readable storage media include: an electrical connection having one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof.

[0187] It will be appreciated by those skilled in the art that all or some of the steps, systems, and functional modules / units in the methods disclosed above may be implemented as software, firmware, hardware, and appropriate combinations thereof. In hardware implementations, the division between the functional modules / units mentioned in the above description does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed by several physical components in cooperation. Some or all components may be implemented as software executed by a processor, such as a digital signal processor or a microprocessor, or implemented as hardware, or implemented as an integrated circuit, such as an application-specific integrated circuit. Such software may be distributed on a computer-readable medium, which may include a computer storage medium (or non-transitory medium) and a communication medium (or temporary medium). As is well known to those skilled in the art, the term computer storage medium includes volatile and non-volatile, removable, and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and can be accessed by a computer. In addition, it is well known to those skilled in the art that communication media generally embodies computer-readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism, and may include any information delivery media.

[0188] It should be noted that the above-described embodiments or implementations are merely illustrative and not restrictive. Therefore, the present disclosure is not limited to what is specifically shown and described herein. Various modifications, substitutions, or omissions may be made to the forms and details of the implementations without departing from the scope of the present disclosure.

Claims

1. A dark spot detection method for a display panel, comprising: Obtaining a first brightness of a plurality of sub-pixels at a first viewing angle; Acquire a first mapping relationship between a first distance and a primary light angle, wherein the first distance is the distance between the sub-pixel and the center of a display area of ​​the display panel, and the primary light angle is the angle between a direction in which the luminous intensity of the sub-pixel is maximum and a direction perpendicular to the display panel; Acquire the brightness of a single sub-pixel at multiple viewing angles to obtain a second mapping relationship between the viewing angle and the brightness of the single sub-pixel; The second brightness of the plurality of sub-pixels at the main light angle is determined according to the acquired first brightness, the first mapping relationship, and the second mapping relationship, and the sub-pixels whose second brightness is lower than a brightness threshold are marked as dark spots.

2. The dark spot detection method according to claim 1, wherein: The display panel includes a first sub-pixel emitting a first color light, a second sub-pixel emitting a second color light, and a third sub-pixel emitting a third color light, and obtaining a first brightness of the plurality of sub-pixels at a first viewing angle includes: The display panel displays a pure color picture of a first color; Using a first testing device to test the first brightness of all the first sub-pixels at a first viewing angle on the entire surface at one time; The display panel displays a pure color picture of a second color; Using the first testing device to test the first brightness of all the second sub-pixels at the first viewing angle at one time; The display panel displays a pure color picture of a third color; The first test device is used to test the first brightness of all the third sub-pixels at the first viewing angle at one time.

3. The dark spot detection method according to claim 2, wherein: The first viewing angle is a 0° viewing angle.

4. The dark spot detection method according to claim 2, wherein: The first testing device is a surface imaging luminance meter or an image type luminance meter.

5. The dark spot detection method according to claim 2, wherein: The first test device meets the following measurement conditions: 0.01 <k1a×Nx / f<0.1; 0.01<k2b×Ny / f<0.1; k1=nx / Nx;k2=ny / Ny; Among them, a is the length of the light-emitting unit in the sub-pixel along the first direction X, b is the length of the light-emitting unit in the sub-pixel along the second direction Y, Nx is the number of light-emitting units of the display panel along the first direction, Ny is the number of light-emitting units of the display panel along the second direction, f is the focal length of the lens of the first test device, nx is the number of light-emitting units within the effective sampling diameter range of the first test device in a plane perpendicular to the plane where the display panel is located, passing through the center line of the first test device, and parallel to the first direction; ny is the number of light-emitting units within the effective sampling diameter range of the first test device in a plane perpendicular to the plane where the display panel is located, passing through the center line of the first test device, and parallel to the second direction.

6. The dark spot detection method according to claim 2, wherein: The sampling viewing angle of the first test device is greater than or equal to A degrees, and A is between 7 and 10.

7. The dark spot detection method according to claim 1, wherein: The obtaining of a first mapping relationship between the first distance and the main light angle includes: Testing the main light angles of sub-pixels at N1 different first distances by a second testing device, where N1 is a natural number greater than 2; By formula fitting, a first mapping formula between the first distance and the main light angle is obtained.

8. The dark spot detection method according to claim 7, wherein: When a formula is fitted for the first mapping relationship between the first distance and the main light angle, a curve corresponding to the first mapping relationship between two adjacent first distances is a straight line.

9. The dark spot detection method according to claim 7, wherein: The second testing device is a spot luminance meter.

10. The dark spot detection method according to claim 1, wherein: The step of acquiring the brightness of a single sub-pixel at multiple viewing angles to obtain a second mapping relationship between the viewing angle and the brightness of the single sub-pixel includes: Testing the brightness value of a single sub-pixel at N2 different viewing angles by a second testing device, wherein N2 is a natural number greater than 2, and the maximum viewing angle among the N2 different viewing angles is greater than or equal to θ1°, and the minimum viewing angle is less than or equal to -θ2°, wherein θ1 is equal to the maximum main light angle value among the main light angles of all sub-pixels, and -θ2 is equal to the minimum main light angle value among the main light angles of all sub-pixels; By formula fitting, a second mapping formula between the viewing angle and the brightness of the single sub-pixel is obtained.

11. The dark spot detection method according to claim 10, wherein: The single sub-pixel is located at the center of the display area of ​​the display panel.

12. The dark spot detection method according to claim 1, wherein: The determining, according to the acquired first brightness, the first mapping relationship, and the second mapping relationship, the second brightness of the plurality of sub-pixels at the main light angle comprises: Determine the sub-pixel (i0, j0) at the main light angle Brightness on For multiple sub-pixels (i, j), perform the following operations respectively: Determine the main light angle CRA of the sub-pixel (i, j) according to the first mapping relationship (i,j) , calculate the difference of the main light angle according to the second mapping relationship The corresponding brightness The brightness of the sub-pixel (i, j) at a 0° viewing angle Sub-pixel (i0, j0) at the main light angle Brightness on And the difference between the main light angle The corresponding brightness Substitute the following calculation formula: Get the sub-pixel (i, j) at the main light angle CRA (i,j) The second brightness Among them, -n1≤i≤n2, -m1≤j≤m2, n1+n2+1 is the number of sub-pixel columns, m1+m2+1 is the number of sub-pixel rows, and n1, n2, m1 and m2 are all natural numbers greater than or equal to 1.

13. The dark spot detection method according to claim 1, wherein: The determining, according to the acquired first brightness, the first mapping relationship, and the second mapping relationship, the second brightness of the plurality of sub-pixels at the main light angle comprises: For multiple sub-pixels (i, j), perform the following operations respectively: Determine the main light angle CRA of the sub-pixel (i, j) according to the first mapping relationship (i,j) ; According to the brightness of sub-pixel (i, j) at 0° viewing angle The main light angle CRA of sub-pixel (i, j) (i,j) And the second mapping relationship between the viewing angle and brightness of a single sub-pixel (i0, j0) is obtained, and the third mapping relationship between the viewing angle and brightness at the sub-pixel (i, j) is obtained. The curve corresponding to the third mapping relationship is about the main light angle CRA (i,j) Symmetrical curves; According to the third mapping relationship, the sub-pixel (i, j) at the main light angle CRA is obtained. (i,j) The second brightness on; Among them, -n1≤i≤n2, -m1≤j≤m2, n1+n2+1 is the number of sub-pixel columns, m1+m2+1 is the number of sub-pixel rows, and n1, n2, m1 and m2 are all natural numbers greater than or equal to 1.

14. The dark spot detection method according to claim 1, wherein: The brightness threshold includes any one of the following: a preset brightness value, an average brightness value of some sub-pixels in the first display area, or an average brightness value of all sub-pixels in the first display area, where the first display area is the entire display screen or a part of the entire display screen.

15. A dark spot detection device for a display panel, comprising a memory; and a processor connected to the memory, wherein the memory is used to store instructions, and the processor is configured to execute the steps of the dark spot detection method for a display panel as described in any one of claims 1 to 14 based on the instructions stored in the memory. 16 . A computer-readable storage medium having a computer program stored thereon, wherein when the program is executed by a processor, the dark spot detection method for a display panel according to claim 1 is implemented.

17. A dark spot detection device for a display panel, comprising: A first acquisition module, a second acquisition module, a third acquisition module and a first processing module, wherein: The first acquisition module is configured to acquire a first brightness of a plurality of sub-pixels at a first viewing angle; The second acquisition module is configured to acquire a first mapping relationship between a first distance and a main light angle, wherein the first distance is the distance between the sub-pixel and the center of the display area of ​​the display panel, and the main light angle is the angle between the direction of maximum luminous intensity of the sub-pixel and the direction perpendicular to the light emitting surface of the display panel; The third acquisition module is configured to acquire the brightness of a single sub-pixel at multiple viewing angles to obtain a second mapping relationship between the viewing angle and the brightness of the single sub-pixel; The first processing module is configured to determine the second brightness of the plurality of sub-pixels at the main light angle according to the acquired first brightness, the first mapping relationship and the second mapping relationship, and mark the sub-pixels whose second brightness is lower than a brightness threshold as dark spots.

18. The dark spot detection device according to claim 17, wherein: The first viewing angle is a 0° viewing angle.

19. The dark spot detection device according to claim 17, wherein: The second acquisition module acquires a first mapping relationship between the first distance and the main light angle, including: Obtaining primary light angles of sub-pixels at N1 different first distances tested by the second testing device, where N1 is a natural number greater than 2; By formula fitting, a first mapping formula between the first distance and the main light angle is obtained.

20. The dark spot detection device according to claim 17, wherein: The third acquisition module acquires the brightness of a single sub-pixel at multiple viewing angles to obtain a second mapping relationship between the viewing angle and the brightness of the single sub-pixel, including: Obtaining brightness values ​​of a single sub-pixel tested by a second test device at N2 different viewing angles, wherein N2 is a natural number greater than 2, and the maximum viewing angle among the N2 different viewing angles is greater than or equal to θ1°, and the minimum viewing angle is less than or equal to -θ2°, wherein θ1 is equal to the maximum principal light angle value among the principal light angles of all sub-pixels, and -θ2 is equal to the minimum principal light angle value among the principal light angles of all sub-pixels; By formula fitting, a second mapping formula between the viewing angle and the brightness of the single sub-pixel is obtained.

21. The dark spot detection device according to claim 17, wherein: The first processing module determines the second brightness of the plurality of sub-pixels at the main light angle according to the acquired first brightness, the first mapping relationship and the second mapping relationship, including: Determine the sub-pixel (i0, j0) at the main light angle Brightness on For multiple sub-pixels (i, j), perform the following operations respectively: Determine the main light angle CRA of the sub-pixel (i, j) according to the first mapping relationship (i,j) , calculate the difference of the main light angle according to the second mapping relationship The corresponding brightness The brightness of the sub-pixel (i, j) at a 0° viewing angle Sub-pixel (i0, j0) at the main light angle Brightness on And the difference between the main light angle The corresponding brightness Substitute the following calculation formula: Get the sub-pixel (i, j) at the main light angle CRA (i,j) The second brightness Among them, -n1≤i≤n2, -m1≤j≤m2, n1+n2+1 is the number of sub-pixel columns, m1+m2+1 is the number of sub-pixel rows, and n1, n2, m1 and m2 are all natural numbers greater than or equal to 1.

22. The dark spot detection device according to claim 17, further comprising: The second processing module comprises: The second processing module is configured to determine whether a one-time full-surface acquisition condition is met based on the attribute information of the light-emitting unit in the display area of ​​the display panel and the acquisition parameters of the first test device, and the first test device is used to obtain the first brightness of multiple sub-pixels at a first viewing angle.

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