Method for determining resistance value of voltage dividing resistor, display panel and display device

Abstract

The application provides a resistance value determination method of a voltage division resistor, a display panel and a display device. When a gamma reference voltage test circuit receives a voltage debugging signal, the initial gamma reference voltage corresponding to the received power supply voltage is obtained through the gamma reference voltage test circuit. The target gamma reference voltage required by the plurality of voltage division resistors can be directly determined according to the initial gamma reference voltage, and the process of frequently replacing resistors is not needed. Then, the appropriate target resistance value can be determined according to the target gamma reference voltage corresponding to the plurality of voltage division resistors. The voltage division resistor of the gamma reference voltage generation circuit is selected according to the target resistance value. It is ensured that the gamma reference voltage generation circuit can generate the relatively accurate target gamma reference voltage based on the target resistance value after receiving the power supply voltage, so as to guarantee the display effect and performance of the display device.

Description

Technical Field

[0001] This application relates to the field of display technology, and in particular to a method for determining the resistance value of a voltage divider resistor, a display panel, and a display device. Background Technology

[0002] Display devices visualize information and data, presenting it to users through specific display technologies. Due to their large information capacity and diverse transmission methods, they have gained widespread application and become dominant. However, in display devices, the gamma circuit directly affects the display effect and performance. Therefore, the tuning of the gamma circuit plays a crucial role in the manufacturing process of display devices. Summary of the Invention

[0003] In view of this, the purpose of this application is to provide a method for determining the resistance value of a voltage divider resistor, a display panel, and a display device to solve or partially solve the above-mentioned technical problems.

[0004] To achieve the above objectives, a first aspect of this application provides a method for determining the resistance value of a voltage divider resistor in a gamma reference voltage generation circuit of a display panel, characterized in that the gamma reference voltage generation circuit includes multiple voltage divider resistors connected in series, the method is applied to a gamma reference voltage testing circuit, the gamma reference voltage testing circuit being electrically coupled to the display panel, and the method comprising:

[0005] In response to the gamma reference voltage test circuit receiving a voltage adjustment signal, it receives the supply voltage and acquires the initial gamma reference voltage corresponding to the supply voltage;

[0006] The target gamma reference voltage corresponding to the plurality of voltage divider resistors is determined based on the initial gamma reference voltage;

[0007] The target resistance value of the plurality of voltage divider resistors is determined based on the target gamma reference voltage corresponding to the plurality of voltage divider resistors.

[0008] Based on the same inventive concept, a second aspect of this application proposes a display panel including a gamma reference voltage generation circuit, the gamma reference voltage generation circuit including a resistor string of a plurality of voltage divider resistors connected in series, the target resistance value of the voltage divider resistors being determined by the method described in the first aspect.

[0009] Based on the same inventive concept, a third aspect of this application proposes a display device including a display panel as described in the second aspect.

[0010] As can be seen from the above, the method for determining the resistance value of the voltage divider resistor, the display panel, and the display device provided in this application, when the gamma reference voltage test circuit receives a voltage adjustment signal, obtains the initial gamma reference voltage corresponding to the received power supply voltage through the gamma reference voltage test circuit. Based on the initial gamma reference voltage, the target gamma reference voltage required by multiple voltage divider resistors can be directly determined without the need for frequent resistor replacement. Then, based on the target gamma reference voltages corresponding to multiple voltage divider resistors, a suitable target resistance value can be determined. By selecting the voltage divider resistors of the gamma reference voltage generation circuit according to the target resistance value, it can be ensured that the gamma reference voltage generation circuit can generate a relatively accurate target gamma reference voltage based on the target resistance value after receiving the power supply voltage, thereby ensuring the display effect and performance of the display device. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in this application or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is a schematic diagram of the gamma circuit according to an embodiment of this application;

[0013] Figure 2 This is a schematic diagram of the voltage-transmittance curves of an embodiment of this application;

[0014] Figure 3 This is a schematic diagram showing the correspondence between grayscale binding points, transmittance, and initial grayscale voltage in an embodiment of this application.

[0015] Figure 4 This is a schematic diagram of a resistor series voltage divider circuit according to an embodiment of this application;

[0016] Figure 5 This is a schematic diagram illustrating the specific adjustment of the resistor in an embodiment of this application;

[0017] Figure 6 This is a schematic diagram of the circuit principle for adjusting the resistance value of the voltage divider resistor in the gamma reference voltage generation circuit of this application embodiment;

[0018] Figure 7 This is a flowchart illustrating the method for determining the resistance value of the voltage divider resistor according to an embodiment of this application;

[0019] Figure 8 This is a schematic diagram of the voltage divider resistor in an embodiment of this application;

[0020] Figure 9This is a schematic diagram illustrating the process of determining the resistance value of the voltage divider resistor in an embodiment of this application; Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0022] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in the embodiments of this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0023] It is understood that before using the technical solutions of the various embodiments in this application, users will be informed of the type, scope of use, and usage scenarios of the personal information involved in an appropriate manner, and user authorization will be obtained.

[0024] For example, upon receiving a user's active request, a prompt message is sent to the user to explicitly inform them that the requested operation will require the acquisition and use of the user's personal information. This allows the user to independently choose, based on the prompt message, whether to provide personal information to the software or hardware such as electronic devices, applications, servers, or storage media performing the operations described in this application.

[0025] As an optional but not limited implementation, in response to a user's active request, sending a prompt message to the user can be done via a pop-up window, where the prompt message can be presented in text format. Furthermore, the pop-up window can also include a selection control allowing the user to choose "agree" or "disagree" to provide personal information to the electronic device.

[0026] It is understood that the above notification and user authorization process is merely illustrative and does not limit the implementation of this application. Other methods that comply with relevant laws and regulations may also be applied to the implementation of this application.

[0027] The embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0028] Display devices can visualize information and data, presenting information to users through specific display technologies. Due to their large amount of information and diverse transmission methods, they have gained the widest application and occupy a dominant position. However, display devices are often prone to problems such as screen flickering and afterimages, resulting in poor display effects.

[0029] This application reveals that one of the reasons for display device problems such as screen flickering and afterimages, resulting in poor display quality, is the deviation between the actual output gamma reference voltage and the expected gamma reference voltage. Therefore, it is necessary to adjust the gamma reference voltage. Currently, in high-resolution LCD products, the adjustment of the gamma reference voltage plays a crucial role in the manufacturing process, as it directly affects the display effect and performance. However, currently, in Full High Definition (FHD) and Quarter High Definition (QHD) display products, such as... Figure 1 As shown, a gamma circuit generally consists of two parts. The first part is a Gamma reference voltage V1 to V14 generated by a Gamma resistor network string R0 to R14 on a PCBA board formed by the mechanical connection between the components and the printed circuit board (PCB). The analog circuit power supply voltage (AVDD) is used as a reference. The second part involves inputting these 14 Gamma reference voltages into a source driver IC (S-IC), which, combined with the resistor network string inside the source driver circuit, generates a full-grayscale voltage (e.g., grayscale values ​​0 to 255 corresponding to grayscale voltages). Since the Gamma resistor network inside the source driver circuit is determined in the integrated circuit (IC) manufacturing process and generally does not require adjustment, adjusting the Gamma reference voltage involves adjusting the Gamma resistor network string on the PCBA board according to actual needs to obtain the required reference voltage (V1 to V14).

[0030] The debugging method for the Gamma resistor network string on this type of PCBA board is as follows:

[0031] (1) As Figure 2 As shown, the voltage-transmittance (VT) curve: measured voltage-transmittance curve test data (brightness and voltage).

[0032] Transmittance calculation: The measured transmittance data is calculated using the following formula:

[0033] Formulas for calculating transmittance at various voltages:

[0034] (2) Adjust the common electrode voltage (Vcom) to make the screen flicker (Flicker) reach the optimal value, and turn on the backlight for half an hour to age.

[0035] (3) Based on the voltage-transmittance curve and the corresponding transmittance of each grayscale binding point (e.g., L255, L223, L191, L127, L63, L31, L0), select the initial grayscale voltage (V1~V14) for each grayscale binding point, such as... Figure 3 As shown.

[0036]

[0037] (4) Based on the voltage-transmittance curve, and adhering to the principles of non-saturation and non-reversal, find the maximum and minimum transmittance values, as well as the corresponding voltage values ​​(V1 and V14). Subtract the two voltages (V1-V14) to obtain the dynamic range of the product. The value of the voltage-transmittance curve is slightly smaller than the maximum value to meet the requirements of different panels.

[0038] MIN value (minimum gamma reference voltage): Selected based on the voltage-transmittance curve, ensuring it is within the inflection point of the voltage-transmittance curve, while the selected MID (intermediate value of gamma reference voltage) must meet the contrast requirements;

[0039] MID value: The voltage corresponding to the lowest point of the voltage-transmittance curve. Driver IC spec: V7 ≥ HAVDD + 0.2V; V8 ≤ HAVDD - 0.2V, where HAVDD is half of the analog circuit power supply voltage (AVDD).

[0040] MAX value (maximum value of gamma reference voltage): According to the principle of voltage symmetry, MAX = MID * 2 - MIN

[0041] (5) Determine the voltage value corresponding to the grayscale binding point. Specifically, find the voltage closest to the corresponding transmittance through the voltage-transmittance curve, and use it as the corresponding gamma reference voltage. Taking V4 and V11 as examples, find the two voltage values ​​corresponding to a transmittance of 21.58% on the voltage-transmittance curve. Through the above steps, the voltages of V1 to V14 can be determined. Offset the calculated values ​​of V1 to V14. Based on experience and the source drive circuit specifications, V14 should be greater than or equal to 0.2V, and the analog circuit power supply voltage AVDD should be 0.2V greater than V1.

[0042] (6) The principle of voltage division using resistor series is as follows: Figure 4As shown, according to the voltage distribution law, the parallel resistance value of the internal and external resistors can be obtained. Then, the resistance value of the resistor in the Gamma resistor network string on the PCBA board can be obtained using the following method:

[0043] In order to find R 外2 For example,

[0044] Among them, V 总 It is the analog circuit power supply (AVDD) voltage; R 总 It is the total resistance; R 内2 It is the internal resistance value of the source drive circuit (S-IC); R 外2 It is the resistance in the Gamma resistor network string; R 并2 It is a parallel resistor.

[0045] For example, such as Figure 5 As shown, the relevant parameters involved in the specific debugging of the resistance values ​​in the Gamma resistor network string are as follows:

[0046] ① Analog circuit power supply (AVDD) voltage: Enter the actual analog circuit power supply voltage value of the product. Requirement: AVDD-V1 > 0.7V.

[0047] ②Voltage: a. The voltage in this line is the initial gamma reference voltage calculated above; b. Note that the HAVDD (half of the analog circuit power supply voltage) voltage must be between V7 and V8 (if the voltage is not between the two, it will affect the adjustment of the gamma reference voltage).

[0048] ③ Current and internal resistance: a. The 9.2mA in the first cell is the current through the resistor in the Gamma resistor network string; b. The values ​​in the other cells are the sum of the internal resistances between adjacent binding points.

[0049] ④ Points: The points corresponding to the various resistors in the Gamma resistor series on the schematic diagram.

[0050] ⑤ Actual required Gamma voltage divider resistor: The actual voltage divider resistor is calculated by dividing the voltage difference between adjacent gamma binding points by the current in the resistor series: Voltage divider resistor = Voltage difference between adjacent binding points / Current * 1000.

[0051] ⑥ Actual integrated circuit (IC) internal resistance: Internal resistance of each driver = total internal resistance / number of flip-chip (COF) films.

[0052] ⑦ Required external resistance value: The internal and external resistances are connected in parallel. Given the actual voltage divider resistor and the actual IC internal resistance, calculate the resistance value of the resistor in the external Gamma resistor network string based on the actual resistance value: External resistance = Voltage divider resistor * Internal resistance / (Internal resistance - Voltage divider resistor)

[0053] ⑧ Resistor library: Since the actual resistance value is not continuous, select the closest available resistor based on the external resistance value calculated in ⑦.

[0054] The process involves testing the Gamma curve and afterimage. If the Gamma curve does not meet the 2.2 requirement or the afterimage does not meet the specifications, this step and subsequent steps are repeated until the Gamma curve and afterimage are properly calibrated. While this process is low-cost, it requires multiple repetitions due to resistance errors and afterimage testing. The calibration process is tedious, time-consuming, and prone to damaging the samples. This is primarily because each calibration requires replacing the resistor, and finding suitable resistor values ​​and replacing resistor strings requires significant time and effort. Furthermore, meeting the standards for the Gamma curve and afterimage during calibration further increases the difficulty and complexity, typically necessitating multiple repetitions of this tedious process.

[0055] Embodiments of this application provide a method for determining the resistance value of a voltage divider resistor in a gamma reference voltage generation circuit of a display panel. The gamma reference voltage generation circuit includes multiple voltage divider resistors connected in series. The method is applied to a gamma reference voltage test circuit, which is electrically coupled to the display panel. Figure 6 A circuit diagram showing the resistance values ​​of the voltage divider resistors in the gamma reference voltage generation circuit provided in this application embodiment is illustrated.

[0056] like Figure 6As shown, based on the principle of adjusting the resistance value of the voltage divider resistor in the gamma reference voltage generation circuit according to embodiments of this application, the debugging circuit may include a gamma reference voltage testing circuit 610 and a gamma reference voltage generation circuit 620. In some embodiments, the debugging circuit may be an external circuit, electrically coupled to the display panel via a connection device such as a connection interface, to provide an electrical signal to it (e.g., to provide a gamma reference voltage to the source drive circuit). In other embodiments, the wiring of the gamma reference voltage testing circuit 610 and the gamma reference voltage generation circuit 620 may be arranged in the non-display area of ​​the display panel and electrically coupled to the source drive circuit of the display panel to provide a gamma reference voltage to the source drive circuit. In some other embodiments, the gamma reference voltage test circuit 610 can be an external circuit, and the wiring of the gamma reference voltage generation circuit 620 can be set in the non-display area of ​​the display panel and electrically coupled to the source drive circuit of the display panel so that after the resistance value of the voltage divider resistor is determined, the arrangement or fabrication of the voltage divider resistor string is completed in the non-display area of ​​the display panel based on the determined resistance value, so that the gamma reference voltage can be provided to the source drive circuit when the display panel is working normally after leaving the factory.

[0057] like Figure 7 As shown, the method includes:

[0058] Step 701: In response to the gamma reference voltage test circuit receiving a voltage adjustment signal, the circuit receives the supply voltage and obtains the initial gamma reference voltage corresponding to the supply voltage.

[0059] In this step, such as Figure 6 As shown, in order to avoid the problems of spending a lot of time and effort to find a suitable resistor value and replace the resistor string during the debugging process of gamma reference voltage, and the debugging process being cumbersome, time-consuming, and prone to sample damage, this application receives the supply voltage and obtains the initial gamma reference voltage corresponding to the supply voltage during the debugging stage, so as to facilitate the subsequent determination of the required target gamma reference voltage.

[0060] Step 702: Determine the target gamma reference voltage corresponding to the plurality of voltage divider resistors based on the initial gamma reference voltage.

[0061] In this step, such as Figure 6As shown, the gamma reference voltage test circuit 610 simplifies the debugging process. It can quickly and directly determine the target gamma reference voltage based on the initial gamma reference voltage, eliminating the need for frequent resistor replacement. During the debugging phase, the gamma reference voltage test circuit 610 provides a stable and accurate target gamma reference voltage (e.g., V1 to V14) to the source driver IC (S-IC). This allows the source driver circuit to generate a grayscale voltage based on the target gamma reference voltage, which in turn drives the display panel to display based on the voltage difference between the common electrode voltage (Vcom) and the grayscale voltage.

[0062] Step 703: Determine the target resistance value of the plurality of voltage divider resistors based on the target gamma reference voltage corresponding to the plurality of voltage divider resistors.

[0063] In this step, such as Figure 6 and Figure 8 As shown, since the gamma reference voltage test circuit 610 determines the required target gamma reference voltage without frequent resistor replacement, the target resistance value of the voltage divider resistor (e.g., R0~R14) to be selected by the gamma reference voltage generation circuit 620 can be directly determined based on this target gamma reference voltage. This avoids sample damage caused by soldering resistors, saving costs. In the verification and mass production stages, the gamma reference voltage generation circuit 620 uses a voltage divider resistor with the target resistance value, and the gamma reference voltage generation circuit 620 acts as the source driver circuit. The IC (S-IC) provides a target gamma reference voltage (e.g., V1 to V14), which enables the source drive circuit to generate a grayscale voltage based on the target gamma reference voltage. This allows the display panel to be driven by the voltage difference between the common electrode voltage (Vcom) and the grayscale voltage, thereby verifying whether the target resistance value of the voltage divider resistor meets the requirements of the gamma curve and afterimage. If it does, the voltage divider resistor of the gamma reference voltage test circuit 610 is selected according to the target resistance value for mass production. Since this method can output a more accurate target gamma reference voltage, it can avoid problems such as screen flicker and afterimage in the display device, thus ensuring the display effect and performance of the display device.

[0064] With the above scheme, when the gamma reference voltage test circuit receives a voltage adjustment signal, it obtains the initial gamma reference voltage corresponding to the received power supply voltage. Based on the initial gamma reference voltage, the target gamma reference voltage required by multiple voltage divider resistors can be directly determined without the need for frequent resistor replacement. Then, based on the target gamma reference voltages corresponding to multiple voltage divider resistors, a suitable target resistance value can be determined. By selecting the voltage divider resistors of the gamma reference voltage generation circuit according to the target resistance value, it can be ensured that the gamma reference voltage generation circuit can generate a relatively accurate target gamma reference voltage based on the target resistance value after receiving the power supply voltage, thereby ensuring the display effect and performance of the display device.

[0065] In some embodiments, step 701, obtaining the initial gamma reference voltage corresponding to the supply voltage, includes:

[0066] Based on a pre-built correspondence between grayscale values ​​and transmittance, an initial gamma reference voltage corresponding to a preset target grayscale value is determined from a pre-built database, wherein the database includes multiple correspondences between initial gamma reference voltages and transmittance.

[0067] In the above scheme, the correspondence between grayscale values ​​and transmittance can be determined as follows:

[0068]

[0069] Where Tr. represents transmittance, Gray Level represents grayscale value, and Gamma is 2.2.

[0070] The database can be a voltage-transmittance (VT) curve. Based on the correspondence between grayscale values ​​and transmittance, the initial gamma reference voltage corresponding to the corresponding grayscale value can be quickly and accurately determined from the voltage-transmittance curve.

[0071] In some embodiments, the display panel includes a source driving circuit, and the gamma reference voltage test circuit is electrically coupled to the display panel through the source driving circuit. The source driving circuit includes a plurality of internal resistors, and the target gamma reference voltage includes a first target voltage and a second target voltage corresponding to the two ends of each of the voltage divider resistors, respectively.

[0072] For each of the voltage divider resistors, step 703 further includes:

[0073] Step A1: Obtain the current value corresponding to the voltage divider resistor, and use the difference between the first target voltage and the second target voltage to perform a ratio operation with the current value corresponding to the voltage divider resistor to obtain the first resistance value of the voltage divider resistor.

[0074] Step A2: Determine the second resistance value of the internal resistance corresponding to the voltage divider resistor in the source drive circuit.

[0075] Step A3: Determine the target resistance value of the voltage divider resistor based on the first resistance value and the second resistance value.

[0076] In the above scheme, the first resistance value of the voltage divider resistor represents the parallel resistance value, and the second resistance value represents the internal resistance value in the source drive circuit (S-IC).

[0077] The actual required voltage divider resistor value (i.e., the first resistance value): The actual required voltage divider resistor value is calculated by dividing the voltage difference between adjacent binding points of Gamma (i.e., the difference between the first target voltage and the second target voltage) by the resistor string current value (i.e., the current value corresponding to the voltage divider resistor): Voltage divider resistor value = voltage difference between adjacent binding points / resistor string current value * 1000.

[0078] The required external resistance value: The internal resistance and the external resistance (i.e., voltage divider resistor) are connected in parallel. Given the actual required voltage divider resistor value and the actual internal resistance of the IC (i.e., the second resistance value), calculate the external Gamma resistance value (i.e., the target resistance value) based on the actual required voltage divider resistor value: External resistance value (i.e., target resistance value) = Voltage divider resistor value * Internal resistance value (Internal resistance value - Voltage divider resistor value). This method can quickly determine the target resistance value.

[0079] In some embodiments, step A2 includes:

[0080] Step A21: Obtain the total resistance value and the total number of internal resistors of the source drive circuit.

[0081] Step A22: The ratio of the total resistance value to the total quantity is used to obtain the second resistance value of the internal resistance.

[0082] In the above scheme, the ratio of the total internal resistance to the total number of internal resistors can be expressed as follows:

[0083] Internal resistance of each driver = total internal resistance / number of COFs

[0084] Among them, the internal resistance of each driver represents the resistance value of each internal resistor (i.e., the second resistance value), the total internal resistance represents the total resistance value of the internal resistors, and the number of COFs represents the total number of internal resistors.

[0085] The resistance value of each internal resistor can be quickly determined by comparing the total resistance value of the internal resistors corresponding to the source drive circuit with the total number of internal resistors.

[0086] In some embodiments, the method is also applied to a gamma reference voltage generation circuit electrically coupled to the display panel, the gamma reference voltage generation circuit including a plurality of first resistors connected in series having target resistance values ​​of the plurality of voltage divider resistors.

[0087] The method further includes:

[0088] The display panel is verified and tested based on the target gamma reference voltage using the gamma reference voltage generation circuit.

[0089] In the above scheme, such as Figure 6 As shown, after determining the target resistance value, the process enters the verification and mass production stage. The gamma reference voltage generation circuit 620 selects multiple first resistors connected in series with the target resistance value of the multiple voltage divider resistors. The gamma reference voltage generation circuit 620 provides the target gamma reference voltage (e.g., V1 to V14) to the source driver IC (S-IC). The source driver IC generates a grayscale voltage based on the target gamma reference voltage, and then drives the display panel to display based on the voltage difference between the common electrode voltage (Vcom) and the grayscale voltage. This verifies whether the target resistance value meets the requirements of the gamma curve and afterimage. If it does, the voltage divider resistors of the gamma reference voltage generation circuit 620 are selected according to the target resistance value for mass production. This ensures that a relatively accurate target gamma reference voltage can be output, thus avoiding problems such as screen flickering and afterimage in the display device, and ensuring the display effect and performance of the display device.

[0090] In some embodiments, the gamma reference voltage generation circuit further includes a plurality of first switching units arranged in parallel, each first switching unit corresponding to a target gamma reference voltage, and the method further includes: controlling the connection state between each voltage divider resistor of the gamma reference voltage generation circuit and the display panel through each first switching unit;

[0091] The step of using the gamma reference voltage generation circuit to perform verification testing on the display panel based on the target gamma reference voltage includes: in each of the first switch units being turned on, using the gamma reference voltage generation circuit to perform verification testing on the display panel based on the target gamma reference voltage.

[0092] In the above scheme, such as Figure 6As shown, after determining the target resistance value, the process enters the verification and mass production stage. The P-Gamma module and R201 to R214 in the gamma reference voltage test circuit 610 are not installed, while the Gamma resistor string module 621 and multiple first switch units 622 (e.g., R101 to R114) in the gamma reference voltage generation circuit 620 are installed. The Gamma resistor string module 621 is selected as multiple first resistors connected in series with the target resistance value having multiple voltage divider resistors. The first switch unit 622 can be a switching device or a 0-ohm resistor to realize the switching function and control the connection state between the gamma reference voltage generation circuit 620 and the display panel.

[0093] When the gamma reference voltage generation circuit 620 is in the ON state with the display panel, it provides a target gamma reference voltage (e.g., V1 to V14) to the source driver IC (S-IC). The source driver IC generates a grayscale voltage based on the target gamma reference voltage, which drives the display panel to display based on the voltage difference between the common electrode voltage (Vcom) and the grayscale voltage. This verifies whether the target resistance value meets the requirements of the gamma curve and afterimage. If it does, the voltage divider resistor of the gamma reference voltage generation circuit 620 is selected according to the target resistance value for mass production to ensure that a more accurate target gamma reference voltage can be output. Therefore, it can avoid problems such as screen flickering and afterimage in the display device, and ensure the display effect and performance of the display device.

[0094] In some embodiments, the gamma reference voltage test circuit includes a plurality of second switching units connected in parallel, each second switching unit corresponding to a target gamma reference voltage, and the method further includes:

[0095] The connection status between the gamma reference voltage test circuit and the display panel is controlled by each of the second switching units.

[0096] In the above scheme, such as Figure 6 As shown, during the debugging phase, the Gamma resistor string module 621 and multiple first switch units 622 (e.g., R101 to R114) in the gamma reference voltage generation circuit 620 are not installed, and the P-Gamma module and multiple second switch units 611 (e.g., R201 to R214) in the gamma reference voltage test circuit 610 are installed. The second switch unit 611 can be a switching device or a 0-ohm resistor to realize the switching function and control the connection state between the gamma reference voltage test circuit 610 and the display panel.

[0097] When the gamma reference voltage test circuit 610 is in the on state with the display panel, the gamma reference voltage test circuit 610 provides a target gamma reference voltage (e.g., V1 to V14) to the source driver IC (S-IC), so that the source driver IC generates a grayscale voltage based on the target gamma reference voltage, and then drives the display panel to display based on the voltage difference between the common electrode voltage (Vcom) and the grayscale voltage.

[0098] In some embodiments, the gamma reference voltage test circuit includes a programmable gamma buffer; determining the target gamma reference voltage corresponding to the plurality of voltage divider resistors based on the initial gamma reference voltage includes: using the programmable gamma buffer to determine the target gamma reference voltage corresponding to the plurality of voltage divider resistors based on the initial gamma reference voltage.

[0099] In the above scheme, such as Figure 6 As shown, the gamma reference voltage test circuit 610 simplifies the debugging process through a programmable gamma buffer (P-Gamma IC). By programming and adjusting the internal resistor network of the programmable gamma buffer, the target gamma reference voltage can be quickly and directly determined based on the initial gamma reference voltage, eliminating the need for frequent resistor replacement.

[0100] In some embodiments, the database construction process includes:

[0101] Step B1: Test the current grayscale brightness of the display panel at each initial gamma reference voltage.

[0102] Step B2: For each initial gamma reference voltage, determine the transmittance based on the corresponding current grayscale brightness and the preset maximum grayscale brightness of the display panel.

[0103] Step B3: Store each initial gamma reference voltage and its corresponding transmittance in the database.

[0104] In the above scheme, an initial gamma reference voltage is applied to the display panel, and the current grayscale brightness under each initial gamma reference voltage is measured using a preset optical instrument. Then, for each initial gamma reference voltage, the transmittance under each initial gamma reference voltage is determined in the following way:

[0105]

[0106] Where Tr. represents transmittance.

[0107] like Figure 2 As shown, the voltage-transmittance curve (VT curve) is stored in the database according to each initial gamma reference voltage and the corresponding transmittance.

[0108] Based on the same inventive concept, embodiments of this application propose a display panel including a gamma reference voltage generation circuit, wherein the gamma reference voltage generation circuit includes a resistor string of multiple voltage divider resistors connected in series, and the target resistance value of the voltage divider resistors is determined by the method described in any of the above embodiments.

[0109] In specific implementation, such as Figure 6 As shown, the display panel includes a gamma reference voltage generation circuit 620. The gamma reference voltage generation circuit 620 includes a resistor string of multiple voltage divider resistors connected in series. During verification and mass production, the target gamma reference voltage determined by the gamma reference voltage test circuit 610 is used to determine the target resistance value of the voltage divider resistors to be used in the resistor string of the gamma reference voltage generation circuit 620. The voltage divider resistors are selected and installed according to this target resistance value, avoiding sample damage caused by soldering resistors and saving costs. Then, the gamma reference voltage generation circuit 620 serves as the source driver circuit. The IC (S-IC) provides a target gamma reference voltage (e.g., V1 to V14), which enables the source drive circuit to generate a grayscale voltage based on the target gamma reference voltage. This grayscale voltage then drives the display panel based on the voltage difference between the common electrode voltage (Vcom) and the grayscale voltage. This verifies whether the target resistance value meets the requirements of the gamma curve and image retention. If it does, the voltage divider resistor of the gamma reference voltage generation circuit 620 is selected according to the target resistance value for mass production. This ensures that a relatively accurate target gamma reference voltage can be output, thus avoiding problems such as screen flicker and image retention, and ensuring display effect and performance.

[0110] Based on the same inventive concept, embodiments of this application propose a display device including the display panel described in the above embodiments.

[0111] In practical implementation, the display device includes a display panel, which includes a gamma reference voltage generation circuit 620. The gamma reference voltage generation circuit 620 includes a resistor string of multiple voltage divider resistors connected in series. During verification and mass production, the target gamma reference voltage determined by the gamma reference voltage test circuit 610 is used to determine the target resistance value of the voltage divider resistors to be used in the resistor string of the gamma reference voltage generation circuit 620. The voltage divider resistors are selected and installed according to this target resistance value, avoiding sample damage caused by soldering resistors and saving costs. Then, the gamma reference voltage generation circuit 620 serves as the source driver circuit. The IC (S-IC) provides a target gamma reference voltage (e.g., V1 to V14), which enables the source drive circuit to generate a grayscale voltage based on the target gamma reference voltage. This allows the display panel to be driven based on the voltage difference between the common electrode voltage (Vcom) and the grayscale voltage, thereby verifying whether the target resistance value meets the requirements of the gamma curve and afterimage. If it does, the voltage divider resistor of the gamma reference voltage generation circuit 620 is selected according to the target resistance value for mass production to ensure that a more accurate target gamma reference voltage can be output. Therefore, it can avoid problems such as screen flickering and afterimage in the display device, and ensure the display effect and performance of the display device.

[0112] In some embodiments, such as Figure 9 As shown, this application will specifically describe the process of determining the resistance value of the voltage divider resistor using an example:

[0113] 1. Determine the voltage-transmittance (VT) curve and calculate the transmittance;

[0114] 2. Adjust the common electrode voltage (Vcom) to make the screen flicker (Flicker) reach the optimal value, and turn on the backlight for half an hour to age it;

[0115] 3. Based on the voltage-transmittance curve and the corresponding relationship of transmittance for each grayscale binding point, determine the initial reference voltage (i.e., the initial gamma reference voltage) (V1~V14) for each grayscale binding point.

[0116] 4. Input the obtained reference voltages (i.e., the initial gamma reference voltages) directly into the P-Gamma control software, and P-Gamma will output the corresponding voltages;

[0117] 5. Test the Gamma curve and afterimage to assess whether they meet specifications;

[0118] 6. If the Gamma curve and afterimage do not meet specifications, calculate the new reference voltage (V1~V14) based on the degree of voltage deviation, input it into P-gamma, and retest the Gamma curve and afterimage. If the Gamma curve and afterimage still do not meet specifications, repeat the above steps until they do.

[0119] 7. Using a reference voltage that meets the specifications (i.e., the target gamma reference voltage), calculate the Gamma resistor string (i.e., the target resistance value) and complete the debugging.

[0120] The traditional Gamma resistor voltage divider method is cumbersome and slow primarily because it involves calculating the Gamma resistor string, finding suitable resistor values, and replacing the resistor string. During debugging, the Gamma curve and afterimage must meet certain standards, requiring this tedious process to be repeated many times. Therefore, the entire process of the traditional Gamma resistor voltage divider method is cumbersome and slow. This application uses a P-gamma IC debugging method, avoiding the repeated processes of calculating the Gamma resistor string, finding suitable resistor values, and replacing the resistor string, thus significantly improving the debugging speed.

[0121] For example, during the debugging process of a display product, the P-gamma module and R201~R214 components are used in the debugging phase.

[0122] The detailed debugging process is as follows:

[0123] 1. Test voltage-transmittance curve.

[0124] 2. Adjust the common electrode voltage to make the screen flicker to the optimal value, Vcom = 4.46V; turn on the backlight and let it age for half an hour.

[0125] 3. Based on the voltage-transmittance curve and the corresponding transmittance of each grayscale binding point, AVDD = 12.2V, HAVDD = 5.9V, and the initial reference voltage (i.e., the initial gamma reference voltage) (V1~V14) of each grayscale binding point are shown in Table 1 below.

[0126] Table 1

[0127] V1 11.32V V8 5.72V V2 10.95V V9 5.08V V3 9.45V V10 3.75V V4 8.72V V11 3.14V V5 8.1V V12 2.4V V6 6.77V V13 0.81V V7 6.36V V14 0.4V

[0128] 4. The obtained reference voltages (i.e., the initial gamma reference voltages) are directly input into the P-Gamma control software (i.e., the gamma reference voltage test circuit).

[0129] 5. Test the Gamma curve and afterimage. After adjusting the reference voltage several times, the Gamma and afterimage specifications are met. The final reference voltage (i.e., the target gamma reference voltage) is shown in Table 2 below.

[0130] Table 2

[0131] V1 11.19V V8 5.6V V2 10.93V V9 5.06V V3 9.41V V10 3.72V V4 8.72V V11 3.14V V5 8.13V V12 2.44V V6 6.79V V13 0.83V V7 6.25V V14 0.25V

[0132] 6. Using a reference voltage that meets the test specifications (i.e., the target gamma reference voltage), calculate the Gamma resistor string (i.e., the target resistance value) as shown in Table 3 below.

[0133] Table 3

[0134]

[0135]

[0136] The final resistance value of the Gamma resistor string (i.e., the target resistance value of the voltage divider resistor) was obtained through debugging. The Gamma resistor string module and R101~R114 components were verified and mass-produced. The resistor string successfully passed the verification and the project was completed for mass production.

[0137] 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 described.

[0138] 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.

[0139] To simplify the description and discussion, and to avoid obscuring the embodiments of this application, the well-known power / ground connections to integrated circuit (IC) chips and other components may or may not be shown in the provided drawings. Furthermore, the apparatus may be shown in block diagram form to avoid obscuring the embodiments of this application, and this also takes into account the fact that the details of the implementation of these block diagram apparatuses are highly dependent on the platform on which the embodiments of this application will be implemented (i.e., these details should be fully understood by those skilled in the art). While specific details (e.g., circuits) are set forth to describe exemplary embodiments of this application, it will be apparent to those skilled in the art that the embodiments of this application can be implemented without these specific details or with variations thereof. Therefore, these descriptions should be considered illustrative rather than restrictive.

[0140] Although this application has been described in conjunction with specific embodiments thereof, many substitutions, modifications, and variations of these embodiments will be apparent to those skilled in the art from the foregoing description. For example, other memory architectures (e.g., dynamic RAM (DRAM)) may be used with the embodiments discussed.

[0141] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of this application (including the claims) is limited to these examples; within the framework of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of the different aspects of this application as described above, which are not provided in the details for the sake of brevity.

[0142] The embodiments of this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of this application should be included within the protection scope of this application.

Claims

1. A method of determining a resistance value of a dividing resistor of a gamma reference voltage generation circuit of a display panel, characterized by, The gamma reference voltage generation circuit includes a plurality of voltage division resistors connected in series, and the method is applied to a gamma reference voltage test circuit, the gamma reference voltage test circuit being electrically coupled to the display panel, and the method includes: In response to the gamma reference voltage test circuit receiving a voltage debugging signal, a supply voltage is received, and an initial gamma reference voltage corresponding to the supply voltage is obtained; A target gamma reference voltage corresponding to the plurality of voltage division resistors is determined according to the initial gamma reference voltage; A target resistance value of the plurality of voltage division resistors is determined according to the target gamma reference voltage corresponding to the plurality of voltage division resistors; The gamma reference voltage test circuit includes a programmable gamma buffer, and the target gamma reference voltage corresponding to the plurality of voltage division resistors is determined according to the initial gamma reference voltage by using the programmable gamma buffer.

2. The method of claim 1, wherein, The initial gamma reference voltage corresponding to the supply voltage is obtained by: Based on a pre-constructed corresponding relationship between gray scale values and transmittances, an initial gamma reference voltage corresponding to a preset target gray scale value is determined from a pre-constructed database, wherein the database includes a plurality of corresponding relationships between initial gamma reference voltages and transmittances.

3. The method of claim 1, wherein, The display panel includes a source driving circuit, the gamma reference voltage test circuit is electrically coupled to the display panel through the source driving circuit, the source driving circuit includes a plurality of internal resistors, and the target gamma reference voltage includes a first target voltage and a second target voltage corresponding to two ends of each voltage division resistor, respectively; For each voltage division resistor, the target resistance value of the plurality of voltage division resistors is determined according to the target gamma reference voltage corresponding to the plurality of voltage division resistors, further including: A current value corresponding to the voltage division resistor is obtained, and a ratio processing is performed on the current value corresponding to the voltage division resistor by using a difference between the first target voltage and the second target voltage, to obtain a first resistance value of the voltage division resistor; A second resistance value of an internal resistor corresponding to the voltage division resistor in the source driving circuit is determined; The target resistance value of the voltage division resistor is determined according to the first resistance value and the second resistance value.

4. The method of claim 3, wherein, The second resistance value of the internal resistor corresponding to the voltage division resistor in the source driving circuit is determined by: A total resistance value of the plurality of internal resistors of the source driving circuit and a total number of the internal resistors are obtained; A ratio processing is performed on the total resistance value and the total number to obtain the second resistance value of the internal resistor.

5. The method of claim 1, wherein, The method is also applied to a gamma reference voltage generation circuit, the gamma reference voltage generation circuit being electrically coupled to the display panel, and the gamma reference voltage generation circuit including a plurality of first resistors connected in series and having target resistance values of the plurality of voltage division resistors; and the method further includes: The display panel is verified and tested by using the gamma reference voltage generation circuit based on the target gamma reference voltage.

6. The method of claim 5, wherein, The gamma reference voltage generation circuit further comprises a plurality of first switch units arranged in parallel, each of the first switch units corresponding to one of the target gamma reference voltages, and the method further comprises: controlling the connection state of each of the first switch units to control the connection state of each of the voltage dividing resistors of the gamma reference voltage generation circuit and the display panel; The verification test of the display panel based on the target gamma reference voltages by the gamma reference voltage generation circuit comprises: performing the verification test of the display panel based on the target gamma reference voltages by the gamma reference voltage generation circuit in the connection state of each of the first switch units.

7. The method of claim 1, wherein, The gamma reference voltage test circuit comprises a plurality of second switch units arranged in parallel, each of the second switch units corresponding to one of the target gamma reference voltages, and the method further comprises: Controlling the connection state of each of the second switch units to control the connection state of the gamma reference voltage test circuit and the display panel.

8. The method of claim 2, wherein, The construction process of the database comprises: Testing the current gray scale brightness of the display panel under each of the initial gamma reference voltages; For each of the initial gamma reference voltages, determining the transmittance according to the corresponding current gray scale brightness and the preset maximum gray scale brightness of the display panel; Storing each of the initial gamma reference voltages and the corresponding transmittance in the database.

9. A display panel, characterized by, A display panel comprising a gamma reference voltage generation circuit, the gamma reference voltage generation circuit comprising a resistor string of a plurality of voltage dividing resistors connected in series, the target resistance values of the voltage dividing resistors being determined by the method of any one of claims 1 to 8.

10. A display device, characterized by comprising: A display panel as claimed in claim 9.

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