A method and device for measuring the voltage holding ratio of a display panel

Abstract

The present invention provides a method and device for measuring the voltage holding ratio of a display panel. The method comprises: determining a corresponding target voltage value on a gamma curve of the display panel based on a target test grayscale; generating a display voltage signal corresponding to the target test grayscale based on the target voltage value; obtaining a brightness change curve of the display panel during a holding phase under the drive of the display voltage signal; and determining the voltage holding ratio of the display panel based on the brightness change curve. After determining the display voltage signal of the display panel, the present invention measures the brightness change curve of the display panel during the holding phase, thereby converting the voltage holding ratio of the liquid crystal display panel into the degree of brightness retention. The voltage holding ratio of the display panel is then obtained based on the brightness change curve, achieving convenient and rapid measurement of the voltage holding ratio.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to a method and device for measuring the voltage holding ratio of a display panel. Background Art

[0002] The operating principle of a liquid crystal display panel is that, under the influence of an electric field, the alignment of liquid crystal molecules changes, causing the light transmitted through the panel to be altered (modulated), achieving electro-optical conversion. Liquid crystal display panels are multi-layer structures composed of various materials and structures. After the liquid crystal module is assembled into a cell, a variety of factors affect the display quality of the LCD panel, including circuit design, thin film transistor (TFT) device performance, alignment layer, and ions in the liquid crystal.

[0003] The voltage holding ratio (VHR) of a liquid crystal display panel refers to the degree to which the liquid crystal layer maintains the written display voltage during the holding phase after the display voltage is written to the liquid crystal layer during the operation of the liquid crystal display panel. Due to the multi-layer structure of liquid crystal display panels, which involves many materials and electrical components, existing technologies make it difficult to easily and quickly measure the specific value of the voltage holding ratio (VHR) of the display panel. Summary of the Invention

[0004] The present invention provides a method and device for measuring the voltage holding ratio of a display panel, which are used to solve the defects in the prior art and realize convenient and rapid measurement of the voltage holding ratio of the display panel.

[0005] In a first aspect, the present invention provides a method for measuring the voltage holding rate of a display panel, comprising: determining a corresponding target voltage value on a gamma curve of a display panel according to a target test grayscale; generating a display voltage signal corresponding to the target test grayscale according to the target voltage value; the display voltage signal is a positive and negative square wave voltage signal relative to a reference voltage of the display panel; the voltage magnitude of the positive and negative square wave signals is the same as the target voltage value; under the drive of the display voltage signal, obtaining a brightness change curve of the display panel in a holding stage; the display voltage signal is a driving signal of the display panel input through a data line; and determining the voltage holding rate of the display panel according to the brightness change curve.

[0006] According to a method for measuring the voltage holding ratio of a display panel provided by the present invention, before determining a corresponding target voltage value on the gamma curve of the display panel according to a target test grayscale, the method includes: obtaining a voltage-transmittance curve of the display panel; and converting the voltage-transmittance curve of the display panel into a gamma curve according to the gamma value of the display panel.

[0007] According to a method for measuring the voltage holding rate of a display panel provided by the present invention, the display voltage signal has a high-level phase and a low-level phase; the high-level phase and the low-level phase are switched alternately frame by frame; the display panel has a charging phase and a holding phase within a frame period driven by the display voltage signal; the holding phase begins after the charging phase ends.

[0008] According to a method for measuring the voltage holding rate of a display panel provided by the present invention, the display voltage signal includes at least a group of high-level stages and low-level stages, and the low-level stage starts after the high-level stage ends; the brightness change curve of the display panel in the holding stage is obtained under the drive of the display voltage signal, including: obtaining a first brightness change curve of the display panel in the first holding stage, and a second brightness change curve of the display panel in the second holding stage; the first holding stage is the holding stage of the display panel driven by the high-level stage; the second holding stage is the holding stage of the display panel driven by the low-level stage; accordingly, determining the voltage holding rate of the display panel according to the brightness change curve includes: determining the voltage holding rate of the display panel according to the first brightness change curve and the second brightness change curve.

[0009] According to a method for measuring the voltage holding rate of a display panel provided by the present invention, the voltage holding rate of the display panel is determined based on the first brightness change curve and the second brightness change curve, including: obtaining a first holding brightness of the first brightness change curve at the end of the first holding stage, and a first maximum brightness within the first holding stage; and obtaining a second holding brightness of the second brightness change curve at the end of the second holding stage, and a second maximum brightness within the second holding stage; and determining the voltage holding rate of the display panel based on the first holding brightness, the first maximum brightness, the second holding brightness and the second maximum brightness.

[0010] According to a method for measuring the voltage holding rate of a display panel provided by the present invention, the voltage holding rate of the display panel is determined based on the first holding brightness, the first maximum brightness, the second holding brightness and the second maximum brightness, including: determining the voltage holding rate based on the average of the first optical voltage holding rate and the second optical voltage holding rate; the first optical voltage holding rate is the ratio of the first holding brightness to the first maximum brightness; the second optical voltage holding rate is the ratio of the second holding brightness to the second maximum brightness.

[0011] According to a method for measuring the voltage holding rate of a display panel provided by the present invention, the voltage holding rate of the display panel is determined based on the first brightness change curve and the second brightness change curve, and also includes: integrating the first brightness change curve in the first holding stage to obtain a first brightness integral; and integrating the first maximum brightness in the first holding stage to obtain a first constant brightness integral; integrating the second brightness change curve in the second holding stage to obtain a second brightness integral; and integrating the second maximum brightness in the second holding stage to obtain a second constant brightness integral; determining the voltage holding rate based on the average of a third optical voltage holding rate and a fourth optical voltage holding rate; the third optical voltage holding rate is the ratio of the first brightness integral to the first constant brightness integral; and the fourth optical voltage holding rate is the ratio of the second brightness integral to the second constant brightness integral.

[0012] According to a method for measuring the voltage holding ratio of a display panel provided by the present invention, when the full grayscale of the display panel is 0 to 255, the target test grayscale is 127.

[0013] In a second aspect, the present invention further provides a device for measuring the voltage holding ratio of a display panel, comprising:

[0014] The first module is used to determine a corresponding target voltage value on a gamma curve of a display panel according to a target test grayscale;

[0015] A second module is configured to generate a display voltage signal corresponding to the target test grayscale according to the target voltage value; the display voltage signal is a positive and negative square wave voltage signal relative to a reference voltage of the display panel; and the voltage magnitude of the positive and negative square wave signals is the same as the target voltage value;

[0016] a third module, configured to obtain a brightness change curve of the display panel in a holding phase under the drive of the display voltage signal; the display voltage signal is a driving signal of the display panel input through a data line;

[0017] The fourth module is configured to determine the voltage holding ratio of the display panel according to the brightness variation curve.

[0018] In a third aspect, the present invention provides an electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the steps of the method for measuring the voltage retention rate of a display panel as described above are implemented.

[0019] In a fourth aspect, the present invention further provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method for measuring the voltage holding ratio of a display panel as described in any one of the above.

[0020] The method and device for measuring the voltage holding ratio of a display panel provided by the present invention can, after determining the display voltage signal of the display panel, measure its brightness change curve during the holding phase of the display panel, thereby converting the voltage holding ratio of the liquid crystal display panel into the degree of brightness retention, and obtaining the voltage holding ratio of the display panel based on the brightness change curve, thereby realizing convenient and rapid measurement of the voltage holding ratio. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 It is a schematic flow chart of a method for measuring the voltage holding ratio of a display panel provided by the present invention;

[0023] Figure 2 is a schematic diagram of a gamma curve of a display panel provided by the present invention;

[0024] Figure 3 1 is a waveform diagram of a display voltage signal provided by the present invention;

[0025] Figure 4 is a schematic diagram of an instrument for optical VHR measurement provided by the present invention;

[0026] Figure 5 is a schematic diagram of a simplified driving model of a liquid crystal display panel provided by the present invention;

[0027] Figure 6 Schematic diagram of the waveform of the square wave driving signal for voltage-transmittance measurement provided by the present invention;

[0028] Figure 7 is a schematic diagram of a voltage-transmittance curve provided by the present invention;

[0029] Figure 8 Schematic diagram of the optical VHR extreme value calculation method provided by the present invention;

[0030] Figure 9 Schematic diagram of the optical VHR integral calculation method provided by the present invention;

[0031] Figure 10 Schematic diagram of the structure of the device for measuring the voltage holding ratio of a display panel provided by the present invention;

[0032] Figure 11 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0033] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0034] It should be noted that in the description of the embodiments of the present invention, the terms "comprise," "include," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprises a..." does not preclude the presence of additional identical elements in the process, method, article, or apparatus comprising the element. Terms such as "upper" and "lower" indicate positions or location relationships based on those shown in the accompanying drawings and are intended solely for ease of description and simplification of the present invention. They are not intended to indicate or imply that the device or element referred to must have a specific orientation, be constructed, or operate in a specific orientation, and are therefore not to be construed as limiting the present invention. Unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be broadly construed, for example, to mean a fixed connection, a detachable connection, or an integral connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediate medium; or internal communication between two elements. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] The terms "first," "second," and the like in this application are used to distinguish similar objects, and are not used to describe a particular order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of this application can be implemented in orders other than those illustrated or described herein. Furthermore, the objects distinguished by "first," "second," and the like generally refer to a class of objects and do not limit the number of objects. For example, the first object may be one or more.

[0036] The following combination Figures 1-11A method and device for measuring the voltage holding ratio of a display panel provided by an embodiment of the present invention are described.

[0037] Figure 1 FIG. 1 is a flow chart of a method for measuring the voltage holding ratio of a display panel provided by the present invention, as shown in FIG. Figure 1 As shown, including but not limited to the following steps:

[0038] Step 101: Determine a corresponding target voltage value on a gamma curve of a display panel according to a target test grayscale.

[0039] Optionally, when the full grayscale of the display panel is 0 to 255, the target test grayscale may be 127. The display panel may be a liquid crystal display panel.

[0040] Figure 2 It is a schematic diagram of the gamma curve of the display panel provided by the present invention. The gamma curve is the grayscale-voltage curve of the display panel. When the target test grayscale is determined, the target voltage value corresponding to the target test grayscale can be determined on the grayscale-voltage curve.

[0041] Optionally, a method for obtaining a gamma curve includes: obtaining a voltage-transmittance curve (VT curve) of the display panel; and converting the voltage-transmittance curve of the display panel into a gamma curve (Gamma curve) according to a gamma value of the display panel. The gamma value is generally 2.2.

[0042] Step 102: Generate a display voltage signal corresponding to the target test grayscale according to the target voltage value.

[0043] Figure 3 Schematic diagram of the waveform of the display voltage signal provided by the present invention, such as Figure 3 As shown, the reference voltage is the Vcom voltage of the display panel. The display voltage signal is a positive and negative square wave voltage signal relative to the Vcom voltage; the voltage magnitude of the positive and negative square wave signal (relative to the reference voltage) is the same as the target voltage value.

[0044] Optionally, the display voltage signal has a high level phase and a low level phase; the voltage in the high level phase is v1, and the voltage in the low level phase is v2.

[0045] The high level phase and the low level phase are switched alternately frame by frame; that is, after a high level phase lasts for one frame period, it switches to a low level phase; after a low level phase lasts for one frame period, it switches to a high level phase, alternating in sequence.

[0046] Step 103: Under the drive of the display voltage signal, obtain a brightness change curve of the display panel in the holding stage.

[0047] The display panel has a charging phase and a holding phase within a frame period driven by the display voltage signal; the holding phase starts after the charging phase ends.

[0048] It should be noted that the display voltage signal is a driving signal for the display panel input via the data line. During the charging phase, the display voltage signal acts on the liquid crystal layer via the data line. However, during the hold phase, the TFT is disconnected from the liquid crystal layer. Although the display voltage signal is still applied to the data line, it does not act on the liquid crystal layer. The specific mechanism of action is described in more detail in the following embodiments.

[0049] Step 104: Determine the voltage holding ratio of the display panel according to the brightness variation curve.

[0050] The brightness change curve reflects the brightness change of the display panel in the holding stage. The present invention can calculate the voltage holding rate of the display panel based on the brightness change curve.

[0051] It should be noted that the brightness change curve here may be one or more, that is, one brightness change curve may be obtained in one holding stage, and multiple corresponding brightness change curves may be obtained in multiple holding stages.

[0052] The voltage holding ratio of the display panel can be calculated based on a brightness change curve. Preferably, the present invention can use multiple brightness change curves to obtain multiple voltage holding ratios respectively, then average the multiple voltage holding ratios and use the final average as the final voltage holding ratio.

[0053] The method for measuring the voltage holding ratio of a display panel provided by the present invention can, after determining the display voltage signal of the display panel, measure its brightness change curve during the holding phase of the display panel, thereby converting the voltage holding ratio of the liquid crystal display panel into the degree of brightness retention, and obtaining the voltage holding ratio of the display panel based on the brightness change curve, thereby realizing convenient and rapid measurement of the voltage holding ratio.

[0054] The present invention uses an optical method to measure the voltage holding ratio of a liquid crystal display panel. This method involves turning on the thin-film transistor (TFT) of the liquid crystal display panel and writing the voltage corresponding to the brightness to be displayed until the panel displays the target brightness. The TFT is then turned off to enter a holding phase, during which the brightness of the liquid crystal display panel gradually decreases. This allows the voltage holding ratio of the liquid crystal display panel to be converted into the degree of brightness retention (the measurement method is referred to as the optical VHR measurement method).

[0055] In order to better illustrate the optical VHR measurement method provided by the present invention, the basic instruments and equipment used in applying the method are first described. Figure 4Schematic diagram of the instrument for optical VHR measurement provided by the present invention, such as Figure 4 As shown, the integrated instrument used in the present invention includes: a light receiving unit, a liquid crystal display panel, a driving unit, a measurement and control system, and a data processing unit.

[0056] The LCD panel needs to be pre-processed to bring out the Vcom, Data, and Gate points of the LCD panel module and connect the test cables to facilitate connection with other instruments and equipment. The LCD panel is a complete LCD panel module to be tested, and a stable and reliable backlight needs to be provided to provide light source for the LCD panel. After the light source passes through the LCD panel module, a light receiving unit is used on the front to measure the brightness of the LCD panel screen. It should be noted that the sampling rate of the brightness value of the light receiving unit is at least 10kSPS. Optionally, the light receiving unit in the present invention adopts a sampling rate of more than 100kSPS to achieve better results.

[0057] Figure 5 This is a simplified driving model diagram of the liquid crystal display panel provided by the present invention, refer to Figure 5 As shown, the driving unit of the present invention can provide the TFT operating state voltage of the liquid crystal display panel, including VGH voltage, VGL voltage, Gate signal voltage, GND voltage, as well as Vcom voltage and Data signal voltage of the liquid crystal display panel. Wherein, DC represents direct current power supply and AC represents alternating current power supply.

[0058] VGH is the voltage required to turn the TFT on, and VGL is the voltage required to turn the TFT off. The Gate signal line applies VGH when it needs to provide a drive signal to the liquid crystal layer via the Data signal line, turning the TFT on. When the Data signal line needs to disconnect the liquid crystal layer, the Gate signal line applies VGL. GND is the circuit reference voltage, and Vcom is the liquid crystal layer reference voltage. The Data signal line carries the display voltage signal to be written to the liquid crystal layer. To prevent polarization, it is typically a positive or negative square wave signal relative to the Vcom voltage.

[0059] The measurement and control system and data processing unit can be composed of a data acquisition card and a computer to provide optical data acquisition and data processing functions, wherein the measurement and control system and data processing unit condition the brightness signal collected by the light receiving unit and convert it into a digital signal, and provide it to the measurement and control system and data processing unit for recording and processing through a suitable communication mode. Commonly used communication modes include USB, network port, etc. Data processing can be processed using general commercial data processing software, or self-written data acquisition and analysis software can be used for processing.

[0060] Alternatively, the present invention may utilize other combinations of instruments and equipment to provide the required signal and brightness data acquisition functions, as long as they can implement the functions of the instruments and equipment described in the above embodiments. For example, the present invention may utilize a photomultiplier tube (PMT) or photodiode for brightness acquisition. The present invention may also utilize multiple programmable power supplies and arbitrary waveform generators to provide TFT and liquid crystal display panel signals and voltages, an oscilloscope with data output for data acquisition and export, and a computer for data processing.

[0061] Based on the contents in the above embodiments, the voltage holding ratio measurement method provided by the present invention is described below in conjunction with specific embodiments.

[0062] (1) During the preparation phase, it is necessary to provide the corresponding operating voltage for the LCD panel module to be tested.

[0063] This circuit primarily provides the VGH, VGL, and GND voltages for the LCD panel, enabling it to properly display different grayscale images. VGH and VGL voltages vary depending on the TFT design of the LCD panel. Typically, VGH can be 15V, VGL can be -8V, GND is the circuit reference voltage of 0V, and Vcom is the reference voltage for the liquid crystal layer of the LCD panel. Typically, a suitable voltage that minimizes panel flicker, such as 6.5V, is used. Of course, the optimal Vcom voltage will vary for different display panels.

[0064] (2) Obtain the voltage-transmittance curve and gamma curve of the liquid crystal display panel.

[0065] Give the Gate signal line VGH voltage to keep the LCD panel TFT open continuously, and give the Data signal line square wave driving signals of different amplitudes from low to high. Figure 6 Schematic diagram of the waveform of the square wave driving signal for voltage-transmittance measurement provided by the present invention, such as Figure 6 As shown, the frequency of the square wave drive signal depends on the design operating frequency of the display panel. For a common 60Hz panel, the drive signal frequency is 30Hz. While providing the Data drive signal, the screen brightness of the LCD panel is also measured simultaneously. Figure 7 is a schematic diagram of the voltage-transmittance curve provided by the present invention, such as Figure 7 As shown, a voltage-transmittance curve can be drawn according to the screen brightness corresponding to different driving voltages.

[0066] Furthermore, according to industry practice, the gamma value is taken as 2.2, and the voltage-transmittance curve is converted into a grayscale-voltage curve (ie, a gamma curve).

[0067] (3) Determine the display voltage signal of the Data signal line (ie, the data line).

[0068] Select the target voltage value corresponding to the target test grayscale in the gamma curve for optical VHR measurement, or select the voltage corresponding to the appropriate transmittance in the VT curve for optical VHR measurement.

[0069] Generally, a brightness point with a grayscale of 10 or above or a transmittance of 8% or above is selected as the measurement point to obtain better optical brightness measurement sensitivity. Preferably, the voltage value corresponding to 50% transmittance or 127 grayscale is selected as the target voltage value to make the brightness change more obvious.

[0070] Based on the content of the display voltage signal introduced in the above embodiment, as Figure 3 As shown, the display voltage signal is a positive and negative square wave voltage signal relative to the Vcom voltage; the voltage magnitude of the positive and negative square wave signal (relative to the Vcom voltage) is the same as the target voltage value.

[0071] The display voltage signal has a high level phase and a low level phase; the high level phase and the low level phase are switched alternately frame by frame.

[0072] (4) Optical VHR measurement of LCD panels.

[0073] The Data signal line (i.e., the data line) is supplied with the display voltage signal required for the target test grayscale. The frequency can range from 60Hz to 0.1Hz, and the frequency can be adjusted based on actual measurement requirements. At the beginning of the positive cycle (high-level phase) and negative cycle (low-level phase) of the display voltage signal, the Gate signal line is supplied with VGH voltage, causing the TFT to open for a very short time (typically 0.3 milliseconds or less; the optimal charging time varies depending on the panel and TFT design). The voltage signal on the Data line is then transmitted to the liquid crystal layer.

[0074] A frame cycle includes a charging phase and a holding phase. The holding phase begins at the end of the charging phase. At this point, the Gate signal line applies a voltage to VGL, turning off the TFTs. The display panel's screen brightness changes throughout the holding phase are measured.

[0075] In one embodiment, the display voltage signal includes at least a set of high-level phases and low-level phases, wherein the low-level phase begins after the high-level phase ends. In a set of positive and negative driving cycles of the Data signal, the positive cycle corresponds to the high-level phase, and the negative cycle corresponds to the low-level phase.

[0076] Based on the contents in the above embodiments, the step of obtaining the brightness change curve of the display panel in the holding stage under the drive of the display voltage signal includes: obtaining a first brightness change curve of the display panel in the first holding stage, and a second brightness change curve of the display panel in the second holding stage; the first holding stage is the holding stage of the display panel driven in the high-level stage; the second holding stage is the holding stage of the display panel driven in the low-level stage; accordingly, the step of determining the voltage holding rate of the display panel according to the brightness change curve includes: determining the voltage holding rate of the display panel according to the first brightness change curve and the second brightness change curve.

[0077] Two methods for determining the voltage holding ratio of the display panel according to the first brightness change curve and the second brightness change curve are introduced below.

[0078] As an optional embodiment, determining the voltage holding ratio of the display panel according to the first brightness change curve and the second brightness change curve includes:

[0079] Acquire a first maintained brightness of the first brightness change curve at the end moment of the first maintained phase, and a first maximum brightness in the first maintained phase; and

[0080] Acquire a second maintained brightness of the second brightness change curve at the end moment of the second maintained stage, and a second maximum brightness in the second maintained stage;

[0081] A voltage holding ratio of the display panel is determined according to the first maintained brightness, the first maximum brightness, the second maintained brightness, and the second maximum brightness.

[0082] Figure 8 Schematic diagram of the optical VHR extreme value calculation method provided by the present invention, such as Figure 8 As shown, the positive cycle corresponds to the high level stage of the display voltage signal, and the negative cycle corresponds to the low level stage of the display voltage signal; the first brightness is maintained at lend1, the first maximum brightness is Lmax1, the second brightness is maintained at lend2, the second maximum brightness is Lmax2, Figure 8 The brightness change waveform shown in includes a first brightness change curve and a second brightness change curve.

[0083] In this embodiment, the voltage holding rate is the average of the first optical voltage holding rate and the second optical voltage holding rate; wherein, the first optical voltage holding rate is the ratio of the first holding brightness lend1 to the first maximum brightness Lmax1; the second optical voltage holding rate is the ratio of the second holding brightness lend2 to the second maximum brightness Lmax2.

[0084] Figure 9 This is a schematic diagram of the optical VHR integral calculation method provided by the present invention, refer to Figure 9 Now, another method for determining the voltage holding ratio of the display panel based on the first brightness change curve and the second brightness change curve is described.

[0085] The first brightness change curve is integrated within the duration corresponding to the first holding stage to obtain a first brightness integral Sreal1; and the first maximum brightness Lmax1 is integrated within the duration corresponding to the first holding stage to obtain a first constant brightness integral Sidel1.

[0086] The second brightness change curve is integrated within the duration corresponding to the second holding stage to obtain a second brightness integral Sreal2; and the second maximum brightness Lmax2 is integrated within the duration corresponding to the second holding stage to obtain a second constant brightness integral Sidel2.

[0087] The voltage maintenance rate is the average of the third optical voltage maintenance rate and the fourth optical voltage maintenance rate; wherein, the third optical voltage maintenance rate is the ratio of the first brightness integral Sreal1 to the first constant brightness integral Sidel1; the fourth optical voltage maintenance rate is the ratio of the second brightness integral Sreal2 to the second constant brightness integral Sidel2.

[0088] To illustrate the advantages of the method for measuring the voltage holding ratio of a display panel provided by the present invention, three liquid crystal display panels were selected for measurement using the method of the present invention. Panels 2 and 3 each had normal display areas (OK areas) and abnormal display areas (NG areas), resulting in five different combined measurement examples. Specific optical VHR measurement data results are shown in Table 1.

[0089] Table 1 VHR measurement results comparison table

[0090] LCD panel Normal frame VHR Negative frame VHR Average VHR Panel 1 61.1％ 86.9％ 74.0％ Panel 2-NG area 43.8％ 83.9％ 63.9％ Panel 2-OK area 61.4％ 86.1％ 73.7％ Panel 3-NG area 78.7％ 92.1％ 85.4％ Panel 3-OK area 85.0％ 92.8％ 88.9％

[0091] As shown in Table 1, the optical VHR in the OK area of Panels 1 and 2 is comparable; however, for Panels 2 and 3, the optical VHR in the OK area is significantly higher than that in the NG area. The positive frame VHR is the VHR value obtained during the first hold phase, while the negative frame VHR is the VHR value obtained during the second hold phase. The average VHR is the final measured voltage holding ratio.

[0092] Figure 10100 is a schematic structural diagram of a device for measuring the voltage holding ratio of a display panel provided by the present invention. The device comprises: a first module 1001 , a second module 1002 , a third module 1003 , and a fourth module 1004 .

[0093] The first module 1001 is configured to determine a corresponding target voltage value on a gamma curve of a display panel according to a target test grayscale;

[0094] The second module 1002 is configured to generate a display voltage signal corresponding to the target test grayscale according to the target voltage value; the display voltage signal is a positive and negative square wave voltage signal relative to a reference voltage of the display panel; and the voltage magnitude of the positive and negative square wave signals is the same as the target voltage value;

[0095] The third module 1003 is configured to obtain a brightness change curve of the display panel in a holding phase under the drive of the display voltage signal; the display voltage signal is a driving signal of the display panel input through the data line;

[0096] The fourth module 1004 is configured to determine a voltage holding ratio of the display panel according to the brightness variation curve.

[0097] It should be noted that the device for measuring the voltage holding ratio of a display panel provided in an embodiment of the present invention can execute the method for measuring the voltage holding ratio of a display panel described in any of the above embodiments during specific operation, which will not be elaborated in this embodiment.

[0098] Figure 11 Schematic diagram of the structure of the electronic device provided by the present invention, such as Figure 11 As shown, the electronic device may include: a processor 1110, a communication interface 1120, a memory 1130, and a communication bus 1140, wherein the processor 1110, the communication interface 1120, and the memory 1130 communicate with each other via the communication bus 1140. The processor 1110 may call logic instructions in the memory 1130 to execute a method for measuring the voltage holding ratio of a display panel, the method comprising: determining a corresponding target voltage value on a gamma curve of the display panel according to a target test grayscale; generating a display voltage signal corresponding to the target test grayscale according to the target voltage value; the display voltage signal is a driving signal of the display panel input through a data line, the display voltage signal is a positive and negative square wave voltage signal relative to a reference voltage of the display panel; the voltage magnitude of the positive and negative square wave signals is the same as the target voltage value; under the drive of the display voltage signal, obtaining a brightness change curve of the display panel in a holding phase; and determining the voltage holding ratio of the display panel according to the brightness change curve.

[0099] In addition, the logic instructions in the above-mentioned memory 1130 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when sold or used as an independent product. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0100] On the other hand, the present invention also provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium, and the computer program includes program instructions. When the program instructions are executed by a computer, the computer can execute the voltage retention rate measurement method of the display panel provided in the above-mentioned embodiments, the method including: determining a corresponding target voltage value on the gamma curve of the display panel according to the target test grayscale; generating a display voltage signal corresponding to the target test grayscale according to the target voltage value; the display voltage signal is a driving signal of the display panel input through the data line, and the display voltage signal is a positive and negative square wave voltage signal relative to the reference voltage of the display panel; the voltage magnitude of the positive and negative square wave signals is the same as the target voltage value; under the drive of the display voltage signal, obtaining the brightness change curve of the display panel in the retention stage; and determining the voltage retention rate of the display panel according to the brightness change curve.

[0101] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to execute the method for measuring the voltage retention rate of the display panel provided in the above-mentioned embodiments, the method comprising: determining a corresponding target voltage value on the gamma curve of the display panel according to the target test grayscale; generating a display voltage signal corresponding to the target test grayscale according to the target voltage value; the display voltage signal is a driving signal of the display panel input through a data line, and the display voltage signal is a positive and negative square wave voltage signal relative to the reference voltage of the display panel; the voltage magnitude of the positive and negative square wave signals is the same as the target voltage value; under the drive of the display voltage signal, obtaining the brightness change curve of the display panel in the retention stage; and determining the voltage retention rate of the display panel according to the brightness change curve.

[0102] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in one location or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of the present embodiment. Persons of ordinary skill in the art will be able to understand and implement the present invention without inventive effort.

[0103] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, or of course, by hardware. Based on this understanding, the essence of the above technical solution or the part that contributes to the existing technology can be embodied in the form of a software product. The computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or certain parts of the embodiments.

[0104] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for measuring the voltage holding ratio of a display panel, characterized in that: include: According to the target test grayscale, determine the corresponding target voltage value on the gamma curve of the display panel; generating a display voltage signal corresponding to the target test grayscale according to the target voltage value; the display voltage signal is a drive signal of the display panel input through the data line, and the display voltage signal is a positive and negative square wave voltage signal relative to a reference voltage of the display panel; the voltage magnitude of the positive and negative square wave voltage signal is the same as the target voltage value; Under the drive of the display voltage signal, obtaining a brightness change curve of the display panel in a holding stage; The voltage holding ratio of the display panel is determined according to the brightness variation curve.

2. The method for measuring the voltage holding ratio of a display panel according to claim 1, wherein: Before determining the corresponding target voltage value on the gamma curve of the display panel according to the target test grayscale, the following steps are included: Obtaining a voltage-transmittance curve of the display panel; The voltage-transmittance curve of the display panel is converted into a gamma curve according to the gamma value of the display panel.

3. The method for measuring the voltage holding ratio of a display panel according to claim 1, wherein: The display voltage signal has a high level phase and a low level phase; the high level phase and the low level phase are switched alternately frame by frame; the display panel has a charging phase and a holding phase within a frame period driven by the display voltage signal; the holding phase starts after the charging phase ends.

4. The method for measuring the voltage holding ratio of a display panel according to claim 3, wherein: The display voltage signal includes at least a set of high-level phases and low-level phases, wherein the low-level phase begins after the high-level phase ends; The step of obtaining a brightness change curve of the display panel in a holding phase under the driving of the display voltage signal includes: Acquire a first brightness change curve of the display panel in a first holding stage, and a second brightness change curve of the display panel in a second holding stage; The first holding stage is a holding stage in which the display panel is driven at the high level stage; the second holding stage is a holding stage in which the display panel is driven at the low level stage; Accordingly, determining the voltage holding ratio of the display panel according to the brightness change curve includes: A voltage holding ratio of the display panel is determined according to the first brightness change curve and the second brightness change curve.

5. The method for measuring the voltage holding ratio of a display panel according to claim 4, wherein: The determining the voltage holding ratio of the display panel according to the first brightness change curve and the second brightness change curve includes: Acquire a first maintained brightness of the first brightness change curve at the end moment of the first maintained phase, and a first maximum brightness in the first maintained phase; and Acquire a second maintained brightness of the second brightness change curve at the end moment of the second maintained stage, and a second maximum brightness in the second maintained stage; A voltage holding ratio of the display panel is determined according to the first maintained brightness, the first maximum brightness, the second maintained brightness, and the second maximum brightness.

6. The method for measuring the voltage holding ratio of a display panel according to claim 5, wherein: The determining the voltage holding ratio of the display panel according to the first maintained brightness, the first maximum brightness, the second maintained brightness, and the second maximum brightness includes: Determining the voltage holding ratio according to an average of the first optical voltage holding ratio and the second optical voltage holding ratio; The first optical voltage holding rate is a ratio of the first held brightness to the first maximum brightness; the second optical voltage holding rate is a ratio of the second held brightness to the second maximum brightness.

7. The method for measuring the voltage holding ratio of a display panel according to claim 5, wherein: The determining the voltage holding ratio of the display panel according to the first brightness change curve and the second brightness change curve further includes: Integrating the first brightness change curve in the first holding phase to obtain a first brightness integral; and Integrating the first maximum brightness in the first holding phase to obtain a first constant brightness integral; Integrating the second brightness change curve in the second holding stage to obtain a second brightness integral; and integrating the second maximum brightness in the second holding stage to obtain a second constant brightness integral; determining the voltage holding ratio according to an average value of the third optical voltage holding ratio and the fourth optical voltage holding ratio; The third optical voltage holding rate is the ratio of the first brightness integral to the first constant brightness integral; the fourth optical voltage holding rate is the ratio of the second brightness integral to the second constant brightness integral.

8. The method for measuring the voltage holding ratio of a display panel according to claim 4, wherein: When the full grayscale of the display panel is 0 to 255, the target test grayscale is 127.

9. A device for measuring the voltage holding ratio of a display panel, characterized in that: include: The first module is used to determine a corresponding target voltage value on a gamma curve of a display panel according to a target test grayscale; A second module is configured to generate a display voltage signal corresponding to the target test grayscale according to the target voltage value; The display voltage signal is a positive and negative square wave voltage signal relative to the reference voltage of the display panel; the voltage magnitude of the positive and negative square wave voltage signal is the same as the target voltage value; a third module, configured to obtain a brightness change curve of the display panel in a holding phase under the drive of the display voltage signal; the display voltage signal is a driving signal of the display panel input through a data line; The fourth module is configured to determine the voltage holding ratio of the display panel according to the brightness variation curve.

10. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the steps of the method for measuring the voltage holding ratio of the display panel according to any one of claims 1 to 7 are implemented.

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