System and method for debugging Gamma curve of liquid crystal display panel

Abstract

The invention provides a debugging system and method for a Gamma curve of a liquid crystal display panel, and the debugging system comprises an upper computer, a signal generator module, a color analyzer module, a drive control chip and an MCU single-chip microcomputer module. According to the Gamma curve debugging method, the Gamma curve debugging system and the Gamma curve debugging system, the Gamma curve debugging system and the Gamma curve debugging system, and corresponding functional algorithms, full-process automation from gray scale output, data acquisition, parameter comparison, parameter modification to final burning can be achieved, manual intervention is not needed, personal errors are eliminated through machine judgment and iteration, and it is ensured that the Gamma curve debugged by each driving block control chip has extremely high consistency and accuracy.

Description

Technical Field

[0001] This invention relates to the field of liquid crystal display driving technology, and in particular to a system and method for adjusting the Gamma curve of a liquid crystal display panel. Background Technology

[0002] In the production of liquid crystal display modules (LCMs), a portion of the function of a TDDI IC is to convert digital signals into analog voltages, thereby controlling the deflection of liquid crystal molecules to achieve grayscale display. However, due to differences in the electro-optical characteristics (voltage-transmittance relationship) of LCD panels from different manufacturers and batches, the Gamma curve (the relationship between optical brightness and input grayscale) displayed by the same TDDI IC will differ when paired with different LCD panels. Different application scenarios and standards employ different Gamma values; for example, Gamma 2.2 is commonly used in PCs and televisions, Gamma 2.4 is often used in professional film and television production, the sRGB standard is close to Gamma 2.2, and some mobile devices may use Gamma 2.0, etc.

[0003] The human eye's perception of light intensity is not linear, but follows an approximately logarithmic pattern. To achieve smoother brightness changes that better match human vision within a limited range of digital grayscale (e.g., 0-255), and to compensate for the inherent electro-optical nonlinearity of CRT displays, the industry employs Gamma correction. For example, the standard Gamma 2.2 curve shows the relationship: `output brightness ∝ (input grayscale)^2.2`. This means that in low grayscale regions (dark areas), more precise voltage control is needed to distinguish subtle brightness changes; while in high grayscale regions (bright areas), voltage changes can be smoother. Achieving the standard Gamma 2.2 curve is crucial for ensuring accurate color reproduction and rich detail in the displayed image.

[0004] Currently, the industry standard practice is for engineers to manually and repeatedly adjust the Gamma parameter using relevant instruments until the measured curve approximates the target Gamma curve. This process is called "Gamma adjustment" or "white balance adjustment".

[0005] Disadvantages of existing technology:

[0006] 1. High dependence on manual labor: The entire process is cumbersome and time-consuming, heavily reliant on the experience and visual judgment of engineers, resulting in poor consistency of results.

[0007] 2. Inefficiency: Completing a full set of Gamma curve debugging from Gray 0 to Gray 255 can take several hours, which severely restricts R&D and production efficiency.

[0008] 3. High cost: It requires expensive manpower and equipment time, and the consistency is poor, with different engineers potentially yielding different results.

[0009] 4. Not suitable for large-scale production: It cannot meet the needs of rapid and standardized debugging of each module on the production line, and the labor and equipment costs remain high.

[0010] 5. The process is cumbersome and prone to errors: manual operation, recording, and verification can easily introduce human error.

[0011] Therefore, a system capable of automatically, accurately, and efficiently adjusting the Gamma parameter of a TDDI IC is particularly important. Summary of the Invention

[0012] The purpose of this invention is to provide a system and method for adjusting the Gamma curve of a liquid crystal display panel to solve the above-mentioned technical problems.

[0013] To address the aforementioned technical problems, based on one aspect of the present invention, the present invention provides a system for adjusting the Gamma curve of a liquid crystal display panel, comprising:

[0014] The host computer stores the target Gamma curve;

[0015] The signal generator module stores grayscale test images Gray 0 to Gray N;

[0016] The color analyzer module is used to measure the optical performance parameters when the liquid crystal display panel displays the grayscale test image, and to feed the optical performance parameters back to the host computer.

[0017] A drive control chip is communicatively connected to the liquid crystal display panel, and the drive control chip stores Gamma parameters.

[0018] The MCU microcontroller module is used to read and write the Gamma parameter of the drive control chip according to the instructions of the host computer.

[0019] The host computer is configured to execute:

[0020] The signal generator module is controlled to output a grayscale test image Gray k to the liquid crystal display panel, where 0 ≤ k ≤ N;

[0021] Read the measured optical values ​​corresponding to the grayscale test image Gray k from the color analyzer module;

[0022] Compare the measured optical value corresponding to the grayscale test image Gray k with the target optical value of the corresponding grayscale test image Gray k in the target Gamma curve;

[0023] If the comparison result between the measured optical value and the target optical value does not meet the preset conditions, the MCU microcontroller module is controlled to adjust the Gamma parameter of the drive control chip until the comparison result meets the preset conditions.

[0024] Optionally, the host computer sequentially controls the adjustment of the Gamma parameters corresponding to each of the grayscale test images Gray 0 to Gray N, and then burns the Gamma parameters corresponding to each grayscale test image that meet the preset conditions to the driver control chip through the MCU microcontroller module.

[0025] Optionally, the host computer sequentially selects multiple grayscale test images from Gray 0 to Gray N at intervals, and sequentially controls the adjustment of the Gamma parameter corresponding to each selected grayscale test image, thereby obtaining the Gamma parameter corresponding to each selected grayscale test image that meets the preset conditions. Furthermore, it generates the Gamma parameter corresponding to each grayscale test image between two adjacent selected grayscale test images based on the interpolation method, and finally burns the Gamma parameters corresponding to each grayscale test image from Gray 0 to Gray N that meet the preset conditions to the driver control chip through the MCU microcontroller module.

[0026] Optionally, the preset condition is configured such that the relative error between the measured optical value and the target optical value is less than or equal to a preset tolerance threshold.

[0027] Optionally, the tolerance threshold is greater than 0% and less than 2%.

[0028] Optionally, the host computer is configured to use a binary search method, gradient descent method, or table lookup method to calculate the Gamma parameter that needs to be adjusted.

[0029] Optionally, the communication protocol between the signal generator and the host computer includes at least one of I2C, UART, and SPI; the communication protocol between the color analyzer module and the host computer is UART; the communication protocol between the MCU microcontroller module and the host computer includes at least one of UART, I2C, and SPI; and the communication protocol between the MCU microcontroller module and the driver control chip includes at least one of I2C and SPI.

[0030] Optionally, the MCU microcontroller module will burn the adjusted gamma parameter that meets the preset conditions into the non-volatile memory of the drive control chip, wherein the non-volatile memory is a one-time programmable memory.

[0031] According to another aspect of the present invention, the present invention also provides a method for adjusting the Gamma curve of a liquid crystal display panel, which includes:

[0032] Step 1: Provide grayscale test images Gray 0 to Gray N;

[0033] Step 2: Output the grayscale test image Gray k to the LCD display panel to read the measured optical value corresponding to the grayscale test image Gray k, where 0≤k≤N;

[0034] Step 3: Compare the measured optical value corresponding to the grayscale test image Gray k with the target optical value of the corresponding grayscale test image Gray k in the pre-stored target Gamma curve;

[0035] Step 4: If the comparison result between the measured optical value and the target optical value does not meet the preset conditions, then adjust the Gamma parameter;

[0036] Step 5: Repeat steps 2 to 4 until the comparison result between the measured optical value and the target optical value meets the preset conditions.

[0037] Optionally, the method further includes:

[0038] The Gamma parameters of each grayscale test image from Gray 0 to Gray N are adjusted sequentially to obtain the adjusted Gamma parameters of each grayscale test image that meet the preset conditions.

[0039] Alternatively, multiple grayscale test images can be selected sequentially at intervals from Gray 0 to Gray N, and the Gamma parameter corresponding to each selected grayscale test image can be adjusted sequentially to obtain the Gamma parameter corresponding to each selected grayscale test image that meets the preset conditions. Furthermore, the Gamma parameter corresponding to each grayscale test image between two adjacent selected grayscale test images can be generated based on the interpolation method, and finally the Gamma parameter corresponding to each grayscale test image from Gray 0 to Gray N that meets the preset conditions can be obtained.

[0040] The system and method for adjusting the Gamma curve of a liquid crystal display panel of the present invention have at least the following technical advantages:

[0041] 1. Fully automated: Through hardware settings of host computer, signal generator module, color analyzer module, drive control chip and MCU microcontroller module, as well as corresponding functional algorithms, the entire process from grayscale output, data acquisition, parameter comparison, parameter modification to final burning can be automated without manual intervention.

[0042] 2. High efficiency and high throughput: Based on the above hardware modules and configured functional algorithms, the manual debugging process that originally required several hours is shortened to minutes, which greatly improves debugging efficiency and is very suitable for large-scale production line operations.

[0043] 3. High precision and consistency: Through machine judgment and iteration, human error is eliminated, ensuring that the Gamma curve of each driver block control chip has extremely high consistency and accuracy.

[0044] 4. Low cost: It reduces reliance on senior technical engineers, saves a lot of labor costs, and improves equipment utilization.

[0045] 5. Flexibility and versatility: By changing the firmware in the MCU module that communicates with different driver control chips, and configuring the host computer protocol, this system can be adapted to various models of driver control chips and LCD display panels, making it highly versatile. Attached Figure Description

[0046] Those skilled in the art will understand that the accompanying drawings are provided to better understand the invention and do not constitute any limitation on the scope of the invention. Wherein:

[0047] Figure 1 This is a schematic diagram of a system for adjusting the Gamma curve of a liquid crystal display panel according to an embodiment of the present invention;

[0048] Figure 2 This is a schematic diagram of a method for adjusting the Gamma curve of a liquid crystal display panel according to an embodiment of the present invention. Detailed Implementation

[0049] To make the objectives, advantages, and features of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and are not drawn to scale, and are only used to facilitate and clarify the explanation of the embodiments of this invention. Furthermore, the structures shown in the drawings are often part of the actual structures. In particular, different figures may emphasize different aspects and may sometimes use different scales.

[0050] As used in this invention, the singular forms “a,” “an,” and “the” include plural objects; the term “or” is generally used to mean “and / or”; the term “a number” is generally used to mean “at least one”; and the term “at least two” is generally used to mean “two or more”. Furthermore, the terms “first,” “second,” and “third” are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as “first,” “second,” or “third” may explicitly or implicitly include one or at least two of that feature. “One end” and “the other end,” as well as “proximal end” and “distal end,” generally refer to two corresponding parts, including not only endpoints. The terms “installed,” “connected,” and “joined” should be interpreted broadly, for example, as a fixed connection, a detachable connection, or an integral part; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediate medium; or a connection within two elements or an interaction between two elements. Furthermore, as used in this invention, the phrase "one element is disposed on another element" generally only indicates that there is a connection, coupling, cooperation, or transmission relationship between the two elements, and the connection, coupling, cooperation, or transmission between the two elements can be direct or indirect through an intermediate element. It should not be construed as indicating or implying a spatial positional relationship between the two elements, i.e., one element can be located arbitrarily inside, outside, above, below, or to one side of the other element, unless otherwise explicitly stated. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0051] See Figure 1 This invention provides a system for debugging the Gamma curve of a liquid crystal display panel 60. The system includes a host computer 10, a signal generator module 20, a color analyzer module 30, and a driver control chip 50. The driver control chip 50 is, for example, a TDDI IC (Touch and Display Driver Integration). The driver control chip 50 is connected to the liquid crystal display panel 60 and stores Gamma parameters. The host computer 10 stores a target Gamma curve. The signal generator module 20 stores grayscale test images Gray 0 to Gray N, for example, from Gray 0 to Gray 255, a total of 256 grayscale test images. The color analyzer module 30 measures the optical performance parameters of the liquid crystal display panel 60 when displaying grayscale test images and feeds these parameters back to the host computer 10. The MCU microcontroller module 40 reads and writes the Gamma parameters of the driver control chip 50 according to instructions from the host computer 10.

[0052] Among them, host computer 10 is configured to execute:

[0053] The control signal generator module 20 outputs a grayscale test image Gray k to the LCD display panel 60, where 0 ≤ k ≤ N;

[0054] Read the measured optical values ​​corresponding to the grayscale test image Gray k from the color analyzer module 30;

[0055] Compare the measured optical value corresponding to the grayscale test image Gray k with the target optical value of the corresponding grayscale test image Gray k in the target Gamma curve.

[0056] If the comparison result between the measured optical value and the target optical value does not meet the preset conditions, the MCU microcontroller module 40 is controlled to adjust the Gamma parameter of the drive control chip 50, and then a new measured optical value is obtained again. The measured optical value and the target optical value are compared again and the Gamma parameter is adjusted until the comparison result meets the preset conditions.

[0057] The MCU microcontroller module 40 will burn the adjusted gamma parameter that meets the preset conditions into the non-volatile memory of the drive control chip 50. The non-volatile memory is a one-time programmable memory.

[0058] In this way, the Gamma parameter corresponding to the grayscale test image Gray k can be adjusted. The Gamma parameter corresponding to other grayscale test images can also be adjusted in the same way.

[0059] This embodiment offers two methods for adjusting the Gamma parameter for each grayscale test image:

[0060] In the first method, the host computer 10 sequentially controls the adjustment of the Gamma parameters corresponding to each of the grayscale test images Gray 0 to Gray N, and then burns the Gamma parameters corresponding to each grayscale test image that meet the preset conditions to the driver control chip 50 through the MCU microcontroller module 40, thereby realizing the optimization and debugging of the Gamma curve.

[0061] The second method involves the host computer 10 sequentially selecting multiple grayscale test images from Gray 0 to Gray N, and sequentially controlling the adjustment of the Gamma parameters corresponding to each selected grayscale test image. This yields Gamma parameters for each selected grayscale test image that meet preset conditions. Furthermore, based on interpolation, the host computer generates Gamma parameters for each grayscale test image between two adjacent selected grayscale test images. The final Gamma parameters for each of the grayscale test images from Gray 0 to Gray N that meet preset conditions are then programmed into the driver control chip 50 via the MCU microcontroller module 40. For example, grayscale test images Gray 0, Gray32, Gray64, Gray128, Gray192, and Gray255 are selected for their respective Gamma parameter adjustments, with the Gamma parameters for intermediate grayscale levels automatically generated using an interpolation algorithm.

[0062] In one embodiment, the preset condition is configured such that the relative error between the measured optical value and the target optical value is less than or equal to a preset tolerance threshold. That is, |measured optical value - target optical value| ≤ tolerance threshold. Optionally, the tolerance threshold is greater than 0% and less than 2%, for example, 1%.

[0063] In one embodiment, the host computer 10 is configured to use a binary search method, gradient descent method, or table lookup method to calculate the Gamma parameter that needs to be adjusted.

[0064] In one embodiment, the communication protocol between the signal generator and the host computer 10 can be at least one of I2C, UART, and SPI; the communication protocol between the color analyzer module 30 and the host computer 10 is UART; the communication protocol between the MCU microcontroller module 40 and the host computer 10 can be at least one of UART, I2C, and SPI; and the communication protocol between the MCU microcontroller module 40 and the driver control chip 50 can be at least one of I2C and SPI.

[0065] Based on the same inventive concept as the above-described debugging system, an embodiment of the present invention also provides a method for debugging the Gamma curve of a liquid crystal display panel 60, see reference. Figure 2 Debugging methods include:

[0066] Step 1: Provide grayscale test images Gray 0 to Gray N;

[0067] Step 2: Output the grayscale test image Gray k to the LCD display panel 60 to read the measured optical value corresponding to the grayscale test image Gray k, where 0≤k≤N;

[0068] Step 3: Compare the measured optical value corresponding to the grayscale test image Gray k with the target optical value of the corresponding grayscale test image Gray k in the pre-stored target Gamma curve;

[0069] Step 4: If the comparison result between the measured optical value and the target optical value does not meet the preset conditions, then adjust the Gamma parameter;

[0070] Step 5: Repeat steps 2 to 4 until the comparison result between the measured optical value and the target optical value meets the preset conditions.

[0071] Optionally, the method further includes: sequentially controlling the adjustment of the Gamma parameters corresponding to each of the grayscale test images Gray 0 to Gray N, and finally obtaining the adjusted Gamma parameters corresponding to each grayscale test image that meet the preset conditions.

[0072] Optionally, the method further includes: sequentially selecting multiple grayscale test images from Gray 0 to Gray N at intervals, and sequentially controlling the adjustment of the Gamma parameter corresponding to each of the selected grayscale test images to obtain the Gamma parameter corresponding to each of the selected grayscale test images that meets the preset conditions; and generating the Gamma parameter corresponding to each grayscale test image between two adjacent selected grayscale test images based on the interpolation method, and finally obtaining the Gamma parameter corresponding to each of the grayscale test images Gray 0 to Gray N that meets the preset conditions.

[0073] Optionally, the preset condition is configured such that the relative error between the measured optical value and the target optical value is less than or equal to a preset tolerance threshold.

[0074] Optionally, the bisection method, gradient descent method, or table lookup method can be used to calculate the Gamma parameter that needs to be adjusted.

[0075] It should be noted that those skilled in the art can understand the debugging method of the present invention based on the foregoing description of the debugging system, and will not repeat the description here.

[0076] Based on the above debugging method, this embodiment of the invention also provides a storage medium on which a program that can be read and written is stored, and when the program is executed, it can implement the above debugging method.

[0077] While the present invention has been disclosed above with reference to preferred embodiments, these embodiments are not intended to limit the invention. For any person skilled in the art, many possible variations and modifications can be made to the technical solutions of the present invention based on the disclosed technical content, or equivalent embodiments can be modified accordingly, without departing from the scope of the present invention. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention, without departing from the content of the present invention, shall still fall within the scope of protection of the present invention.

Claims

1. A system for adjusting the Gamma curve of a liquid crystal display panel, characterized in that, include: The host computer stores the target Gamma curve; The signal generator module stores grayscale test images Gray 0 to Gray N; The color analyzer module is used to measure the optical performance parameters when the liquid crystal display panel displays the grayscale test image, and to feed the optical performance parameters back to the host computer. A drive control chip is communicatively connected to the liquid crystal display panel, and the drive control chip stores Gamma parameters. The MCU microcontroller module is used to read and write the Gamma parameter of the drive control chip according to the instructions of the host computer. The host computer is configured to execute: The signal generator module is controlled to output a grayscale test image Gray k to the liquid crystal display panel, where 0 ≤ k ≤ N; Read the measured optical values ​​corresponding to the grayscale test image Gray k from the color analyzer module; Compare the measured optical value corresponding to the grayscale test image Gray k with the target optical value of the corresponding grayscale test image Gray k in the target Gamma curve; If the comparison result between the measured optical value and the target optical value does not meet the preset conditions, the MCU microcontroller module is controlled to adjust the Gamma parameter of the drive control chip until the comparison result meets the preset conditions.

2. The system for adjusting the Gamma curve of a liquid crystal display panel according to claim 1, characterized in that, The host computer sequentially controls the adjustment of the Gamma parameters corresponding to each of the grayscale test images Gray 0 to Gray N, and then burns the Gamma parameters corresponding to each grayscale test image that meet the preset conditions to the driver control chip through the MCU microcontroller module.

3. The system for adjusting the Gamma curve of a liquid crystal display panel according to claim 1, characterized in that, The host computer sequentially selects multiple grayscale test images from Gray 0 to Gray N at intervals, and sequentially controls the adjustment of the Gamma parameter corresponding to each selected grayscale test image, thereby obtaining the Gamma parameter corresponding to each selected grayscale test image that meets the preset conditions. Furthermore, it generates the Gamma parameter corresponding to each grayscale test image between two adjacent selected grayscale test images based on the interpolation method, and finally burns the Gamma parameters corresponding to each grayscale test image from Gray 0 to Gray N that meet the preset conditions into the driver control chip through the MCU microcontroller module.

4. The system for adjusting the Gamma curve of a liquid crystal display panel according to claim 1, characterized in that, The preset condition is configured such that the relative error between the measured optical value and the target optical value is less than or equal to a preset tolerance threshold.

5. The system for adjusting the Gamma curve of a liquid crystal display panel according to claim 4, characterized in that, The tolerance threshold is greater than 0% and less than 2%.

6. The system for adjusting the Gamma curve of a liquid crystal display panel according to claim 1, characterized in that, The host computer is configured to use a binary search method, gradient descent method, or table lookup method to calculate the Gamma parameter that needs to be adjusted.

7. The system for adjusting the Gamma curve of a liquid crystal display panel according to claim 1, characterized in that, The communication protocol between the signal generator and the host computer includes at least one of I2C, UART, and SPI; the communication protocol between the color analyzer module and the host computer is UART; the communication protocol between the MCU microcontroller module and the host computer includes at least one of UART, I2C, and SPI; and the communication protocol between the MCU microcontroller module and the driver control chip includes at least one of I2C and SPI.

8. The system for adjusting the Gamma curve of a liquid crystal display panel according to claim 1, characterized in that, The MCU microcontroller module will burn the adjusted gamma parameter that meets the preset conditions into the non-volatile memory of the drive control chip. The non-volatile memory is a one-time programmable memory.

9. A method for adjusting the Gamma curve of a liquid crystal display panel, characterized in that, include Step 1: Provide grayscale test images Gray 0 to Gray N; Step 2: Output the grayscale test image Gray k to the LCD display panel to read the measured optical value corresponding to the grayscale test image Gray k, where 0≤k≤N; Step 3: Compare the measured optical value corresponding to the grayscale test image Gray k with the target optical value of the corresponding grayscale test image Gray k in the pre-stored target Gamma curve; Step 4: If the comparison result between the measured optical value and the target optical value does not meet the preset conditions, then adjust the Gamma parameter; Step 5: Repeat steps 2 to 4 until the comparison result between the measured optical value and the target optical value meets the preset conditions.

10. The method for adjusting the Gamma curve of a liquid crystal display panel according to claim 9, characterized in that, The method further includes: The Gamma parameters of each grayscale test image from Gray 0 to Gray N are adjusted sequentially to obtain the adjusted Gamma parameters of each grayscale test image that meet the preset conditions. Alternatively, multiple grayscale test images can be selected sequentially at intervals from Gray 0 to Gray N, and the Gamma parameter corresponding to each selected grayscale test image can be adjusted sequentially to obtain the Gamma parameter corresponding to each selected grayscale test image that meets the preset conditions. Furthermore, the Gamma parameter corresponding to each grayscale test image between two adjacent selected grayscale test images can be generated based on the interpolation method, and finally the Gamma parameter corresponding to each grayscale test image from Gray 0 to Gray N that meets the preset conditions can be obtained.

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