Liquid crystal display panel state evaluation method and apparatus, electronic device, and storage medium

Abstract

A liquid crystal display panel state evaluation method and apparatus, an electronic device, and a storage medium. The liquid crystal display panel (1) comprises an alignment film (5), a common electrode (42), a pixel electrode (41), and a liquid crystal layer (3). The method comprises: providing a target direct current signal to the common electrode (42) or the pixel electrode (41) of the liquid crystal display panel (1), and acquiring ion accumulation data; according to the ion accumulation data and the target direct current signal, determining the type of ions in the liquid crystal display panel (1), which helps to determine the cause of afterimage, thereby specifically eliminating afterimage in the liquid crystal display panel (1).

Description

Methods, apparatus, electronic devices and storage media for assessing the condition of liquid crystal display panels Cross-referencing

[0001] This application claims priority to Chinese Patent Application No. 202411661321.6, filed on November 20, 2024, entitled “Method, Apparatus, Electronic Device and Storage Medium for Evaluating the State of a Liquid Crystal Display Panel”, the entire disclosure of which is incorporated herein by reference. Technical Field

[0002] This disclosure relates to the field of liquid crystal display technology, and in particular to a method, apparatus, electronic device and storage medium for evaluating the condition of a liquid crystal display panel. Background Technology

[0003] Liquid crystal display (LCD) panels are a widely used flat panel display technology. Their core technology lies in utilizing changes in the optical properties of liquid crystal materials to display images. With its advantages of low power consumption, thin and light design, and no radiation, LCD panel technology occupies an important position in televisions, computer monitors, mobile phones, tablets, and various instrument displays.

[0004] Image retention, or image ghosting, refers to the phenomenon where, after a liquid crystal display (LCD) panel has displayed a fixed image for an extended period, the previous image remains when switching to another image; this image retention can affect the normal display of the panel. There are many causes of image retention, and compared to DC-type image retention, AC-type image retention is more complex and its mechanisms are harder to determine. One cause of AC-type image retention is stray ions in the liquid crystal layer and alignment film of the LCD panel. Determining the type of stray ions in the display panel is a significant technical challenge. Summary of the Invention

[0005] To address the aforementioned technical problems, this disclosure provides a method, apparatus, electronic device, and storage medium for evaluating the condition of a liquid crystal display panel.

[0006] This disclosure provides a method for evaluating the state of a liquid crystal display panel, the liquid crystal display panel including an alignment film, a common electrode, a pixel electrode, and a liquid crystal layer; the method includes: providing a target DC signal to the common electrode or the pixel electrode of the liquid crystal display panel, while acquiring ion accumulation data; and determining the ion type in the liquid crystal display panel based on the ion accumulation data and the target DC signal.

[0007] Optionally, the alignment film includes alignment film ions, and the liquid crystal layer includes liquid crystal layer ions; determining the ion type in the liquid crystal display panel includes: determining the magnitude relationship between the concentration of the alignment film ions and the concentration of the liquid crystal layer ions in the liquid crystal display panel.

[0008] Optionally, the ion accumulation data includes data on the change of common voltage on the common electrode over time; determining the ion type in the liquid crystal display panel based on the ion accumulation data and the target DC signal includes: determining the ion type in the liquid crystal display panel based on the data on the change of common voltage over time and the polarity of the target DC signal.

[0009] Optionally, the alignment film includes alignment film ions, and the liquid crystal layer includes liquid crystal layer ions; providing a target DC signal to the common electrode or the pixel electrode of the liquid crystal display panel while acquiring ion accumulation data includes: providing the target DC signal to the common electrode of the liquid crystal display panel while acquiring the ion accumulation data; determining the ion type in the liquid crystal display panel based on the common voltage change data over time and the polarity of the target DC signal includes: determining that the concentration of alignment film ions in the liquid crystal display panel is less than the concentration of liquid crystal layer ions in response to the common voltage increasing over time and the target DC signal being positive, or the common voltage decreasing over time and the target DC signal being negative; or, determining that the concentration of alignment film ions in the liquid crystal display panel is greater than the concentration of liquid crystal layer ions in response to the common voltage increasing over time and the target DC signal being negative, or the common voltage decreasing over time and the target DC signal being positive.

[0010] Optionally, the alignment film includes alignment film ions, and the liquid crystal layer includes liquid crystal layer ions; providing a target DC signal to the common electrode or the pixel electrode of the liquid crystal display panel while acquiring ion accumulation data includes: providing the target DC signal to the pixel electrode of the liquid crystal display panel while acquiring the ion accumulation data; determining the ion type in the liquid crystal display panel based on the common voltage change data over time and the polarity of the target DC signal includes: determining that the concentration of alignment film ions in the liquid crystal display panel is greater than the concentration of liquid crystal layer ions in response to the common voltage increasing over time and the target DC signal being positive, or the common voltage decreasing over time and the target DC signal being negative; or, determining that the concentration of alignment film ions in the liquid crystal display panel is less than the concentration of liquid crystal layer ions in response to the common voltage increasing over time and the target DC signal being negative, or the common voltage decreasing over time and the target DC signal being positive.

[0011] Optionally, the common voltage change data over time is the common voltage change data over time corresponding to the liquid crystal display panel maintaining minimum flicker and / or minimum brightness.

[0012] Optionally, the method further includes: stopping the supply of the target DC signal to the common electrode or the pixel electrode of the liquid crystal display panel, while acquiring ion release data; and determining the image retention risk of the liquid crystal display panel based on the ion release data.

[0013] Based on the same inventive concept, this disclosure also provides a liquid crystal display panel state evaluation device, the liquid crystal display panel including an alignment film, a common electrode, a pixel electrode, and a liquid crystal layer; the device includes: a testing module, used to provide a target DC signal to the common electrode or the pixel electrode of the liquid crystal display panel, and simultaneously acquire ion accumulation data; a calculation module, used to determine the ion type in the liquid crystal display panel based on the ion accumulation data and the target DC signal.

[0014] Based on the same inventive concept, this disclosure also provides an electronic device, including: a processor; a memory for storing executable instructions; wherein the processor is used to read the executable instructions from the memory and execute the executable instructions to implement the liquid crystal display panel state evaluation method.

[0015] Based on the same inventive concept, this disclosure also provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the processor implements the liquid crystal display panel state evaluation method.

[0016] Compared with the prior art, the technical solution provided in this disclosure has the following advantages: The method provided in this disclosure superimposes a DC signal on the liquid crystal display panel, causing ions in the display panel to accumulate under the action of an electric field, and determines the type of stray ions in the display panel by using ion accumulation data, which helps to determine the cause of image retention, and thus can specifically eliminate image retention in the liquid crystal display panel. Attached Figure Description

[0017] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0018] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 is a schematic cross-sectional view of a liquid crystal display panel provided in an embodiment of this disclosure;

[0020] Figure 2 is a flowchart illustrating a liquid crystal display panel status evaluation method provided in an embodiment of this disclosure;

[0021] Figure 3 is a schematic diagram of the structure of an apparatus for performing a liquid crystal display panel state evaluation method according to an embodiment of the present disclosure;

[0022] Figure 4 is a schematic diagram of a liquid crystal display panel driving model provided in an embodiment of this disclosure;

[0023] Figure 5 is a graph showing the relationship between the system common voltage and the common voltage provided in the embodiments of this disclosure.

[0024] Figure 6 is a cross-sectional structure and ion distribution diagram of a liquid crystal display panel provided in an embodiment of this disclosure;

[0025] Figure 7 is a cross-sectional structure and ion distribution diagram of another liquid crystal display panel provided in an embodiment of this disclosure;

[0026] Figure 8 is a cross-sectional structure and ion distribution diagram of another liquid crystal display panel provided in an embodiment of this disclosure;

[0027] Figure 9 is a cross-sectional structure and ion distribution diagram of another liquid crystal display panel provided in an embodiment of this disclosure;

[0028] Figure 10 is a cross-sectional structure and ion distribution diagram of another liquid crystal display panel provided in an embodiment of this disclosure;

[0029] Figure 11 is a cross-sectional structure and ion distribution diagram of another liquid crystal display panel provided in an embodiment of this disclosure;

[0030] Figure 12 is a graph obtained when evaluating the state of different liquid crystal materials and alignment films according to an embodiment of this disclosure;

[0031] Figure 13 is a schematic diagram of a liquid crystal display panel status evaluation device provided in an embodiment of this disclosure;

[0032] Figure 14 is a schematic diagram of an electronic device structure provided in an embodiment of this disclosure. Detailed Implementation

[0033] To better understand the above-mentioned objectives, features, and advantages of the embodiments of this disclosure, the solutions of the embodiments of this disclosure will be further described below. It should be noted that, unless otherwise specified, the embodiments of this disclosure and the features within them can be combined with each other.

[0034] Numerous specific details are set forth in the following description in order to provide a full understanding of the embodiments of this disclosure, but the embodiments of this disclosure may also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only some embodiments of the embodiments of this disclosure, and not all embodiments.

[0035] Liquid crystal display technology is based on the special properties of liquid crystal molecules. While naturally arranged in an ordered manner, these molecules can rearrange themselves in response to changes in an electric field, thus affecting the transmission of light. As shown in Figure 1, a basic liquid crystal display panel 1 consists of two glass substrates 2 (specifically, a lower glass substrate 21 and an upper glass substrate 22), a liquid crystal layer 3 sandwiched between them, and transparent electrodes 4 covering the surface of the glass substrates 2 near the liquid crystal layer 3. One substrate has electrodes divided into pixel sizes, connected to a thin-film transistor (TFT) array, controlling the brightness of each pixel; this electrode is also called the pixel electrode 41. The other substrate typically has a common electrode 42. When a voltage is applied between the pixel electrode 41 and the common electrode 42, the resulting electric field causes the liquid crystal molecules in the liquid crystal layer 3 to rearrange, changing the polarization state of light passing through the liquid crystal layer 3, thereby controlling the transmission or blocking of light.

[0036] Specifically, as shown in Figure 1, between the liquid crystal layers 3 and the transparent electrodes 4 on both sides, the liquid crystal display panel 1 also includes an alignment layer 5 (specifically, a lower alignment layer 51 and an upper alignment layer 52). The alignment layer is one of the key components of the liquid crystal display panel. Its function is to guide the liquid crystal molecules to align in a specific direction, thereby precisely controlling the transmission of light and achieving a clear and high-quality display effect.

[0037] The surface of the alignment film has a microstructure or has undergone physical or chemical treatment to form uniaxial or multiaxial ordered microgrooves or specific chemical functional groups. These structures or functional groups exert interaction forces on the liquid crystal molecules, causing them to align neatly along a specific direction. In the unenergized state, the liquid crystal molecules maintain their initial alignment state. When energized, the molecules rearrange under the influence of the electric field, changing the polarization state of light, thereby controlling the transmission and blocking of light, creating changes in brightness, and achieving image display.

[0038] During the manufacturing process of liquid crystal display panels, various impurities may be mixed into the liquid crystal layer and alignment film, thereby forming stray ions in the liquid crystal layer and alignment film. The migration of stray ions in the liquid crystal display panel will cause image retention.

[0039] In view of this, one embodiment of the present disclosure provides a method for evaluating the state of a liquid crystal display panel. The liquid crystal display panel, as shown in FIG1, includes an alignment film 5, a common electrode 42, a pixel electrode 41, and a liquid crystal layer 3.

[0040] As shown in Figure 2, the method provided in this embodiment includes:

[0041] S1. Provide a target DC signal to the common electrode or pixel electrode of the liquid crystal display panel, and simultaneously acquire ion accumulation data.

[0042] Specifically, the ions here refer to stray ions. The target DC signal can create a new electric field in the liquid crystal display panel, inducing stray ions in the liquid crystal display panel to accumulate in the electric field, thereby obtaining ion accumulation data.

[0043] In specific implementation, the process of providing the target DC signal to the liquid crystal display panel in S1 above specifically includes:

[0044] A reference voltage is provided to the common electrode of the liquid crystal display panel, while a display driving signal superimposed on the target DC signal is provided to the pixel electrode of the liquid crystal display panel. Alternatively, a display driving signal is provided to the pixel electrode of the liquid crystal display panel, while a reference voltage superimposed on the target DC signal is provided to the common electrode of the liquid crystal display panel.

[0045] In other words, when providing the target DC signal to the liquid crystal display panel in S1 above, it is necessary to provide a reference voltage for normal display to the common electrode of the liquid crystal display panel and a display drive signal for normal display to the pixel electrode. Then, the target DC signal is superimposed on the signal of the common electrode or the pixel electrode and provided to the liquid crystal display panel. The normal display drive signal and the reference voltage enable the liquid crystal display panel to display a specific grayscale, such as displaying a 255 grayscale image (white image).

[0046] S2. Determine the ion type in the liquid crystal display panel based on the ion accumulation data and the target DC signal.

[0047] Since stray ions exist in both the liquid crystal layer and the alignment film to varying degrees, and the liquid crystal layer and the alignment film are located in different positions (the liquid crystal layer is a single layer located in the middle, while the alignment film is located on both sides of the liquid crystal layer), the ion accumulation data exhibited by the stray ions in the liquid crystal layer and the alignment film are different in the electric field generated by the target DC signal. Therefore, the ion type in the display panel can be determined based on the above ion accumulation data.

[0048] The method provided in this disclosure superimposes a DC signal onto a liquid crystal display panel, causing ions in the display panel to accumulate under the influence of an electric field. The type of stray ions in the display panel is determined by the ion accumulation data, which helps to determine the cause of image retention and thus enables targeted elimination of image retention in the liquid crystal display panel.

[0049] Figure 3 shows a schematic diagram of the structure and connection relationship of the device used to perform the above method. As shown in the figure, the device consists of a liquid crystal display panel 1, a light receiving unit 102, a driving unit 103, a measurement and control system, and a data processing unit 104. A simplified driving model of the liquid crystal display panel 1 is shown in Figure 4. The liquid crystal display panel 1 is the complete liquid crystal display panel module under test, including a stable and reliable backlight to provide a light source for the panel. The liquid crystal display panel needs to be pre-processed, with the common electrode, pixel electrode, and other electrical interfaces of the liquid crystal display panel module brought out and connected to test cables for easy connection to the above device and data acquisition. Measurement can also be performed using a system board projection mode, with only the common electrode or pixel electrode brought out, or full communication command control. Those skilled in the art can choose a suitable connection scheme to achieve the input of the target DC signal depending on the panel configuration.

[0050] The light receiving unit 102 is used to measure the screen brightness of the liquid crystal display panel. The light receiving unit 102 needs a sampling rate of at least 10kSPS (samples per second) to sample the brightness value, and preferably uses a sampling rate of more than 100kSPS to achieve better results.

[0051] Figure 4 shows a simplified driving model of a liquid crystal display panel according to an embodiment of the present disclosure. As shown in the figure, the driving unit 103 provides the operating state voltages of the thin-film transistors (TFTs) in the liquid crystal display panel, including the TFT turn-on voltage (VGH), the TFT turn-off voltage (VGL), and typically VGH can be +15V and VGL can be -8V (the optimal operating voltage will be different for different TFT designs), the TFT gate signal voltage, the electrical reference ground voltage (GND), and the common voltage (Vcom) of the common electrode. Typically, a suitable voltage that minimizes flickering of the liquid crystal display panel can be selected, such as 5.3V (the optimal Vcom voltage will vary for different panels).

[0052] The pixel electrode receives the source (Data) signal voltage of the thin-film transistor, which is usually a positive and negative AC square wave voltage signal with Vcom as the reference potential. The signal frequency varies depending on the panel design, for example, 60Hz, and the signal amplitude varies depending on the grayscale to be displayed.

[0053] The measurement and control system and data processing unit 104 are used to receive the brightness signal collected by the optical receiving unit 102 and to condition and convert the brightness signal into a digital signal. The optical receiving unit 102 provides the data to the measurement and control system and data processing unit 104 for recording and processing through a suitable communication mode. Commonly used communication modes include analog signals, USB, and network ports. The data can be processed using general commercial data processing software, or it can be processed by those skilled in the art by writing their own measurement and control and data acquisition and analysis software based on the methods provided in the above embodiments of this disclosure, so as to realize the control of the measurement system workflow and the automated processing function after the data is acquired and entered into the computer.

[0054] The apparatus described in this embodiment can also be replaced by other general-purpose instruments to achieve the same function. For example, a high-speed luminance meter can be used to implement the function of a light receiving unit, a multi-channel programmable power supply and an arbitrary waveform generator can be used to implement the function of a driving unit, and a data acquisition card, a computer and software running on it can be used to implement a measurement and control system and a data processing unit. Those skilled in the art can select according to the actual situation, and there are no excessive limitations here.

[0055] In practice, the liquid crystal display panel needs to be pre-processed by disconnecting the common voltage or transistor source signal voltage supply on its own circuit board, and by bonding wires to allow the driving unit to provide the common voltage or transistor source signal for operation to the liquid crystal display panel through external injection (or by controlling the common voltage or transistor source signal of the liquid crystal display panel through remote or local communication). Then, a DC bias voltage (i.e., the aforementioned target DC signal) is superimposed on the common electrode or pixel electrode of the entire liquid crystal display panel.

[0056] In practice, the target DC signal can be a DC bias voltage of 0.1V-5V, preferably a DC bias voltage of about 1V.

[0057] In some embodiments, the alignment film includes alignment film ions, and the liquid crystal layer includes liquid crystal layer ions; the step of determining the ion type in the liquid crystal display panel in S2 specifically includes:

[0058] Determine the relationship between the concentration of alignment film ions and the concentration of liquid crystal layer ions in the liquid crystal display panel. Specifically, the relationship is defined as the concentration of alignment film ions in the liquid crystal display panel being greater than, less than, or equal to the concentration of liquid crystal layer ions.

[0059] Since both the liquid crystal layer and the alignment film contain stray ions to varying degrees, and their positions are different (the liquid crystal layer is a single layer located in the middle, while the alignment film is located on both sides of the liquid crystal layer), the ion accumulation data exhibited by the stray ions in the liquid crystal layer and the alignment film are different in the electric field generated by the target DC signal. Therefore, the relationship between the concentration of ions in the alignment film and the concentration of ions in the liquid crystal layer in the liquid crystal display panel can be determined by the ion accumulation data.

[0060] By identifying which ion concentration is higher in the liquid crystal display panel, it is possible to determine which factor is causing image retention to a greater extent, and then to make targeted improvements and eliminate it. Specifically, in one embodiment, if it is determined that the liquid crystal layer of the liquid crystal display panel has a higher ion concentration, it can be determined that the liquid crystal layer of the display panel does not meet the quality requirements, and the image retention problem can be improved by replacing the liquid crystal layer.

[0061] In some embodiments, the ion accumulation data includes time-varying data of the common voltage on the common electrode, and S2 includes:

[0062] S21. Determine the ion type in the liquid crystal display panel based on the data of the change of common voltage over time and the polarity of the target DC signal.

[0063] In one specific embodiment, the common voltage change over time data refers to the common voltage change over time corresponding to the liquid crystal display panel maintaining minimum flicker and / or minimum brightness. Specifically, the liquid crystal display panel may flicker in some flicker test images. The aforementioned minimum flicker and minimum brightness refer to the change in the current common voltage corresponding to the process of maintaining minimum flicker / minimum brightness at the current grayscale under the test image by adjusting the magnitude of the common voltage. It should be noted that when the liquid crystal display panel is normally lit, it provides an initial system common voltage to the common electrode. The system common voltage is the common voltage corresponding to the minimum flicker / minimum brightness at the current grayscale under the initial test image, as shown in Figure 5. The system common voltage is a fixed voltage value. The common voltage that changes over time in the above embodiments of this disclosure is obtained by continuously adjusting the curves in Figure 5 (including curves T1 and T2, where curve T1 is the relationship curve between the common voltage and brightness / flicker at time T1, and curve T2 is the relationship curve between the common voltage and brightness / flicker at time T2, with time T2 being later than time T1). When the brightness / flicker of the curve is at its minimum, the corresponding common voltage is taken. This common voltage is the common voltage that changes over time. The common voltage that changes over time in other embodiments of this disclosure is similar and will not be described again.

[0064] Since stray ions exist to varying degrees in both the liquid crystal layer and the alignment film, and the liquid crystal layer and the alignment film are located in different positions (the liquid crystal layer is a single layer located in the middle, while the alignment film is located on both sides of the liquid crystal layer), and the electric field directions generated by target DC signals with different polarities are also different, the stray ions in the liquid crystal layer and the alignment film can generate a common voltage in different electric field directions, resulting in different offset data (i.e., the aforementioned common voltage change data over time). Therefore, the type of ions in the liquid crystal display panel can be determined based on the aforementioned common voltage change data over time and the polarity of the target DC signal.

[0065] In some embodiments, if a target DC signal is provided to the common electrode of the liquid crystal display panel in S1 above, and ion accumulation data is acquired simultaneously, then the steps in S21 above specifically include:

[0066] In response to the common voltage increasing over time and the target DC signal being positive, or the common voltage decreasing over time and the target DC signal being negative, it is determined that the concentration of alignment film ions in the liquid crystal display panel is less than the concentration of liquid crystal layer ions; or, in response to the common voltage increasing over time and the target DC signal being negative, or the common voltage decreasing over time and the target DC signal being positive, it is determined that the concentration of alignment film ions in the liquid crystal display panel is greater than the concentration of liquid crystal layer ions.

[0067] In other embodiments, if a target DC signal is provided to the pixel electrode of the liquid crystal display panel in S1 above, and ion accumulation data is acquired simultaneously, then the steps in S21 above specifically include:

[0068] In response to the common voltage increasing over time and the target DC signal being positive, or the common voltage decreasing over time and the target DC signal being negative, it is determined that the concentration of alignment film ions in the liquid crystal display panel is greater than the concentration of liquid crystal layer ions; or, in response to the common voltage increasing over time and the target DC signal being negative, or the common voltage decreasing over time and the target DC signal being positive, it is determined that the concentration of alignment film ions in the liquid crystal display panel is less than the concentration of liquid crystal layer ions.

[0069] Taking the provision of a target DC signal to the common electrode of the liquid crystal display panel as an example, Figure 6 shows the random distribution of stray ions in the liquid crystal layer 3 without an external electric field, and Figure 7 shows the ion distribution in the liquid crystal layer 3 after a positive voltage target DC signal is provided to the common electrode 42 of the liquid crystal display panel. As shown in Figure 7, the first direction X is the electric field direction of the external electric field E0 formed by the target DC signal. This external electric field induces the stray ions in the liquid crystal layer 3 to be distributed as shown in Figure 7 (positive ions + move along the first direction X, negative ions - move along the second direction Y opposite to the first direction X; the same applies to the following embodiments, and will not be repeated). In this way, the direction of the electric field E1 formed by the stray ions is the second direction Y opposite to the first direction X. In order to keep the liquid crystal display panel from flickering and / or brightness to be minimized, the electric field formed by the stray ions in the liquid crystal layer 3 will cause the common voltage to increase over time. Similarly, providing a negative voltage to the common electrode 42 of the liquid crystal display panel will cause the electric field formed by the stray ions in the liquid crystal layer 3 to decrease the common voltage over time, and will not be repeated.

[0070] Figure 8 shows the random distribution of stray ions in the alignment film 5 without an external electric field, and Figure 9 shows the ion distribution in the alignment film 5 after a positive DC signal is applied to the common electrode 42 of the liquid crystal display panel. As shown in Figure 9, the first direction X is the electric field direction of the external electric field E0 formed by the target DC signal, and the external electric field E0 induces the stray ions in the alignment film 5 to be distributed as shown in Figure 9. Unlike the liquid crystal layer 3, since the alignment film 5 includes a lower alignment film 51 and an upper alignment film 52, stray ions not only form an electric field in one alignment film, but also form a new electric field between the two alignment films, namely the first electric field E21 and the second electric field E22 shown in Figure 9. The first electric field E21 is formed by the positive ions+ in the upper alignment film 52 and the negative ions- in the lower alignment film 51, and the direction of the electric field is the second direction Y, which is opposite to the first direction X. The second electric field E22 is formed by the positive ions+ in the lower alignment film 51 and the negative ions- in the upper alignment film 52, and the direction of the electric field is the first direction X. Because the second electric field E22 operates at a closer distance, its equivalent electric field strength is stronger. The combined electric field E2, resulting from the superposition of the first and second electric fields E21, has the same electric field direction as the second electric field E22 (i.e., the aforementioned first direction X), and consequently, the same electric field direction as the applied electric field E0 formed by the target DC signal. To minimize flicker and / or brightness in the liquid crystal display panel, the electric field formed by stray ions in the alignment film 5 causes the common voltage to decrease over time. Similarly, applying a negative voltage to the common electrode 42 of the liquid crystal display panel causes the electric field formed by stray ions in the alignment film 5 to increase the common voltage over time, which will not be elaborated further.

[0071] Figure 10 shows the random distribution of stray ions in the entire display panel without an external electric field. Figure 11 shows the ion distribution in the entire display panel after a positive DC target signal is applied to the common electrode 42 of the liquid crystal display panel. The applied electric field E0, the electric field E1 formed by liquid crystal layer ions, and the electric field E2 formed by alignment film ions are shown in Figure 11. When the concentration of alignment film ions in the liquid crystal display panel is less than the concentration of liquid crystal layer ions, the electric field E1 formed by liquid crystal layer ions dominates. The direction of the electric field formed by stray ions in the entire display panel is the same as E1 and opposite to the applied electric field E0, causing the common voltage to increase over time. When the concentration of alignment film ions in the liquid crystal display panel is greater than the concentration of liquid crystal layer ions, the electric field E2 formed by alignment film ions dominates. The direction of the electric field formed by stray ions in the entire display panel is the same as E2 and the same as the applied electric field E0, causing the common voltage to decrease over time. The same principle applies to applying a negative DC target signal to the common electrode 42 of the liquid crystal display panel, and will not be elaborated further.

[0072] This disclosure takes providing a target DC signal to the common electrode of a liquid crystal display panel as an example to further describe the principle of determining the ion type. Those skilled in the art can understand the principle corresponding to the embodiment of providing a target DC signal to the pixel electrode of a liquid crystal display panel based on the content, and this disclosure will not repeat it again.

[0073] In practice, there may be situations where the common voltage does not change over time. In such cases, the concentration of alignment film ions in the liquid crystal display panel can be considered to be equivalent to the concentration of liquid crystal layer ions. At this time, the effects of alignment film ions and liquid crystal layer ions on the liquid crystal display panel can be approximately canceled out, thereby avoiding the generation of image retention.

[0074] In some embodiments, the above method further includes:

[0075] S3. Stop providing the target DC signal to the common electrode or pixel electrode of the liquid crystal display panel, and simultaneously acquire ion release data.

[0076] S4. Determine the risk of image retention in the liquid crystal display panel based on ion release data.

[0077] Ion release data reflects the ease with which the electric field generated by ion accumulation is released, thus assessing the impact of ion adsorption on image retention in the display panel. Generally, the faster the recovery of the common voltage shift over time, the faster the ion release, and the easier it is for the image retention generated by the liquid crystal display panel to dissipate. Conversely, if the recovery of the common voltage shift over time is slow, it indicates that the ions are not easily released, and the image retention generated by the liquid crystal display panel is not easily dissipated. Even when the concentrations of alignment film ions and liquid crystal layer ions are comparable, although they may approximately cancel each other out under the target DC signal, there may still be a common voltage shift due to the different release rates of alignment film ions and liquid crystal layer ions during the ion release process, thus worsening image retention. Using the aforementioned ion release data, the risk of image retention in the liquid crystal display panel can be further assessed when the concentrations of alignment film ions and liquid crystal layer ions are comparable.

[0078] Other combinations, such as different migration rates and concentrations of ions in the liquid crystal layer and the alignment layer, can be analyzed on a case-by-case basis according to the above basic principles. All combinations will not be explained here.

[0079] Furthermore, under the same conditions, the magnitude of the offset of the common voltage of different liquid crystal display panels also reflects the difference in ion concentration. Generally, the larger the offset of the common voltage, the greater the ion concentration, which can be used as a reference for the horizontal evaluation of different liquid crystal display panels.

[0080] It should be noted that although the method provided in this disclosure uses a target DC signal as an excitation to induce ion shift, in actual liquid crystal display panels, due to various reasons such as process, design, and circuit, an equivalent DC voltage of varying magnitude will always be generated, inducing ion adsorption and thus causing image retention problems. Even under ideal conditions, where the liquid crystal display panel does not have an equivalent DC signal, the presence of alignment layer ions and liquid crystal layer ions will still cause adsorption under the drive of a symmetrical electric field, which may still cause image retention problems. The ion concentration detected by the above method can assess the risk of image retention in the liquid crystal display panel.

[0081] In specific implementation, S1 involves providing a target DC signal to the common electrode or pixel electrode of the liquid crystal display panel to accumulate ions. This process is maintained for a period of time to obtain the ion accumulation data. This period can typically be maintained from 10 minutes to 168 hours; for short-term evaluation, it can be set to 60 minutes. During this time, ion accumulation data is acquired periodically, for example, every 5 minutes. Then, in the second stage, the supply of the target DC signal to the common electrode or pixel electrode of the liquid crystal display panel is stopped, and the ion release process begins. This process is maintained for a period of time, typically from 10 minutes to 168 hours; for short-term evaluation, it can be set to 60 minutes. During this time, ion release data is also acquired periodically, for example, every 5 minutes.

[0082] The holding time used in the experiment can be adjusted to a suitable value according to different liquid crystal display panels. The appropriate standard is to meet the evaluation of the performance specifications of the liquid crystal display panel. For example, a specification of about 1 hour can be used to evaluate the short-term ion movement status, and a specification of about 168 hours (7 days) can be used to evaluate the long-term slow ion movement status difference, so as to more accurately determine the ion type in the liquid crystal display panel.

[0083] In one specific embodiment, the method described above was used to evaluate the condition of various liquid crystal layers and various alignment films. The evaluation results are shown in Figure 12. 98109 and BY21-J39A represent the types of liquid crystal layers, while 1A6071, 7951, 7951_02R3, and DFS represent the types of alignment films. Figure 12 shows the change in the common voltage of each configuration of the liquid crystal display panel over time under the condition of minimum brightness. Specifically, Figure 12 shows the data obtained after 1 hour of ion accumulation (before time T0) and 1 hour of ion release (after time T0) at 127 gray levels when a target DC signal of +1V is provided to the common electrode. As can be seen from Figure 12, different combinations of liquid crystal layers and different alignment films result in different ion movement patterns. For example, in the display panel composed of the BY21-J39A liquid crystal layer and the DFS alignment film, the common voltage increases significantly during the ion accumulation stage, indicating that liquid crystal layer ions are the dominant factor in this display panel. In contrast, in the display panel composed of the BY21-J39A liquid crystal layer and the 7951_02R3 alignment film, the common voltage decreases significantly during the ion accumulation stage, indicating that alignment film ions are the dominant factor in this display panel.

[0084] It should be noted that the method in this embodiment can be executed by a single device, such as a computer or server. The method can also be applied in a distributed scenario, where multiple devices cooperate to complete the task. In such a distributed scenario, one of these devices may execute only one or more steps of the method in this embodiment, and the multiple devices will interact with each other to complete the method.

[0085] It should be noted that the above description describes some embodiments of this application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in a different order than that shown in the above embodiments and still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require a specific or sequential order to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0086] Based on the same inventive concept, corresponding to the methods of any of the above embodiments, this application also provides a liquid crystal display panel state evaluation device, as shown in FIG1. ​​The liquid crystal display panel includes an alignment film 5, a common electrode 42, a pixel electrode 41, and a liquid crystal layer 3.

[0087] As shown in Figure 13, the apparatus provided in this embodiment includes:

[0088] Test module 10 is used to provide a target DC signal to the common electrode or pixel electrode of the liquid crystal display panel, and at the same time acquire ion accumulation data;

[0089] The calculation module 20 is used to determine the ion type in the liquid crystal display panel based on the ion accumulation data and the target DC signal.

[0090] The apparatus provided in this embodiment superimposes a DC signal onto a liquid crystal display panel, causing ions in the display panel to accumulate under the influence of an electric field. By using the ion accumulation data, the type of stray ions in the display panel can be determined, which helps to determine the cause of image retention and thus enables targeted elimination of image retention in the liquid crystal display panel.

[0091] For ease of description, the above devices are described in terms of function, divided into various modules. Of course, in implementing this application, the functions of each module can be implemented in one or more software and / or hardware.

[0092] The apparatus described above is used to implement the corresponding liquid crystal display panel state evaluation method in any of the foregoing embodiments, and has the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0093] Figure 14 shows a schematic diagram of the structure of an electronic device provided in an embodiment of this disclosure.

[0094] As shown in Figure 14, the electronic device may include a processor 1101 and a memory 1102 storing computer program instructions.

[0095] Specifically, the processor 1101 may include a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits that can be configured to implement the embodiments of this application.

[0096] Memory 1102 may include a mass storage device for information or instructions. For example, and not limitingly, memory 1102 may include a hard disk drive (HDD), a floppy disk drive, flash memory, optical disk, magneto-optical disk, magnetic tape, or a Universal Serial Bus (USB) drive, or a combination of two or more of these. Where appropriate, memory 1102 may include removable or non-removable (or fixed) media. Where appropriate, memory 1102 may be internal or external to the integrated gateway device. In a particular embodiment, memory 1102 is a non-volatile solid-state memory. In a particular embodiment, memory 1102 includes read-only memory (ROM). Where appropriate, the ROM may be a mask-programmed ROM, a programmable ROM (PROM), an erasable PROM (EPROM), an electrically erasable programmable PROM (EEPROM), an electrically alterable ROM (EAROM), or flash memory, or a combination of two or more of these.

[0097] The processor 1101 reads and executes computer program instructions stored in the memory 1102 to perform the steps of the liquid crystal display panel state evaluation method provided in this embodiment of the present disclosure.

[0098] In one example, the electronic device may also include a transceiver 1103 and a bus 1104. As shown in FIG14, the processor 1101, memory 1102 and transceiver 1103 are connected via bus 1104 and communicate with each other.

[0099] Bus 1104 may include hardware, software, or both. For example, and not limitingly, the bus may include an Accelerated Graphics Port (AGP) or other graphics bus, an Extended Industry Standard Architecture (EISA) bus, a Front Side Bus (FSB), a Hyper Transport (HT) interconnect, an Industrial Standard Architecture (ISA) bus, an Infinite Bandwidth Interconnect, a Low Pin Count (LPC) bus, a memory bus, a Micro Channel Architecture (MCA) bus, a Peripheral Component Interconnect (PCI) bus, a PCI-Express (PCI-X) bus, a Serial Advanced Technology Attachment (SATA) bus, a Video Electronics Standards Association Local Bus (VLB) bus, or other suitable buses, or a combination of two or more of these. Where appropriate, bus 1104 may include one or more buses. Although specific buses are described and illustrated in the embodiments of this application, this application considers any suitable bus or interconnection.

[0100] The following are embodiments of the computer-readable storage medium provided in this disclosure. This computer-readable storage medium and the liquid crystal display panel state evaluation method of the above embodiments belong to the same inventive concept. For details not described in detail in the embodiments of the computer-readable storage medium, please refer to the embodiments of the liquid crystal display panel state evaluation method described above.

[0101] This embodiment provides a storage medium containing computer-executable instructions, which, when executed by a computer processor, are used to perform a liquid crystal display panel state evaluation method.

[0102] Of course, the computer-executable instructions provided in the embodiments of this disclosure are not limited to the above-described method operations, but can also perform related operations in the liquid crystal display panel state evaluation method provided in any embodiment of this disclosure.

[0103] Based on the above description of the implementation methods, those skilled in the art can clearly understand that this disclosure can be implemented using software and necessary general-purpose hardware, and of course, it can also be implemented using hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this disclosure, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk, or optical disk, etc., including several instructions to cause a computer cloud platform (which may be a personal computer, server, or network cloud platform, etc.) to execute the liquid crystal display panel status evaluation method provided in the various embodiments of this disclosure.

[0104] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the aforementioned element.

[0105] The foregoing description is merely a specific embodiment of this disclosure, enabling those skilled in the art to understand or implement it. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this disclosure. Therefore, this disclosure is not to be limited to the embodiments described above, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for evaluating the condition of a liquid crystal display panel, characterized in that, The liquid crystal display panel includes an alignment film, a common electrode, a pixel electrode, and a liquid crystal layer; The method includes: A target DC signal is provided to the common electrode or the pixel electrode of the liquid crystal display panel, while ion accumulation data is acquired. The ion type in the liquid crystal display panel is determined based on the ion accumulation data and the target DC signal.

2. The method according to claim 1, characterized in that, The alignment film includes alignment film ions, and the liquid crystal layer includes liquid crystal layer ions; Determining the ion type in the liquid crystal display panel includes: Determine the relationship between the concentration of ions in the alignment film and the concentration of ions in the liquid crystal layer in the liquid crystal display panel.

3. The method according to claim 1, characterized in that, The ion accumulation data includes data on the change of the common voltage on the common electrode over time; The step of determining the ion type in the liquid crystal display panel based on the ion accumulation data and the target DC signal includes: The ion type in the liquid crystal display panel is determined based on the time-varying data of the common voltage and the polarity of the target DC signal.

4. The method according to claim 3, characterized in that, The alignment film includes alignment film ions, and the liquid crystal layer includes liquid crystal layer ions; The step of providing a target DC signal to the common electrode or the pixel electrode of the liquid crystal display panel, while simultaneously acquiring ion accumulation data, includes: The target DC signal is provided to the common electrode of the liquid crystal display panel, while the ion accumulation data is acquired. Determining the ion type in the liquid crystal display panel based on the time-varying data of the common voltage and the polarity of the target DC signal includes: In response to the common voltage increasing over time and the target DC signal being positive, or the common voltage decreasing over time and the target DC signal being negative, it is determined that the concentration of alignment film ions in the liquid crystal display panel is less than the concentration of liquid crystal layer ions; Alternatively, in response to the common voltage increasing over time and the target DC signal being negative, or the common voltage decreasing over time and the target DC signal being positive, it is determined that the concentration of alignment film ions in the liquid crystal display panel is greater than the concentration of liquid crystal layer ions.

5. The method according to claim 3, characterized in that, The alignment film includes alignment film ions, and the liquid crystal layer includes liquid crystal layer ions; The step of providing a target DC signal to the common electrode or the pixel electrode of the liquid crystal display panel, while simultaneously acquiring ion accumulation data, includes: The target DC signal is provided to the pixel electrode of the liquid crystal display panel, while the ion accumulation data is acquired. Determining the ion type in the liquid crystal display panel based on the time-varying data of the common voltage and the polarity of the target DC signal includes: In response to the common voltage increasing over time and the target DC signal being positive, or the common voltage decreasing over time and the target DC signal being negative, it is determined that the concentration of alignment film ions in the liquid crystal display panel is greater than the concentration of liquid crystal layer ions; Alternatively, in response to the common voltage increasing over time and the target DC signal being negative, or the common voltage decreasing over time and the target DC signal being positive, it is determined that the concentration of alignment film ions in the liquid crystal display panel is less than the concentration of liquid crystal layer ions.

6. The method according to claim 3, characterized in that, The common voltage change data over time refers to the common voltage change data of the liquid crystal display panel when maintaining minimum flicker and / or minimum brightness over time.

7. The method according to claim 1, characterized in that, Also includes: Stop providing the target DC signal to the common electrode or the pixel electrode of the liquid crystal display panel, and simultaneously acquire ion release data; The risk of image retention in the liquid crystal display panel is determined based on the ion release data.

8. A liquid crystal display panel condition evaluation device, characterized in that, The liquid crystal display panel includes an alignment film, a common electrode, a pixel electrode, and a liquid crystal layer; The device includes: The test module is used to provide a target DC signal to the common electrode or the pixel electrode of the liquid crystal display panel, and at the same time acquire ion accumulation data; The calculation module is used to determine the ion type in the liquid crystal display panel based on the ion accumulation data and the target DC signal.

9. An electronic device, characterized in that, include: processor; Memory, used to store executable instructions; The processor is configured to read the executable instructions from the memory and execute the executable instructions to implement the method of any one of claims 1-7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, The storage medium stores a computer program that, when executed by a processor, causes the processor to implement the method of any one of claims 1-7.

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