LCD display screen color correction system and method

Abstract

The present invention relates to the technical field of display screen correction, specifically a color correction system and method for an LCD display screen. The method comprises dividing the LCD display screen into a plurality of independent correction zones, obtaining display parameters for each correction zone; constructing a color difference compensation matrix for the correction zones based on the difference between the display parameters of each correction zone and a preset standard value, and fitting the linear compensation coefficients of the RGB channels using the least squares method; smoothing the compensation matrices of adjacent correction zones using a bilinear interpolation algorithm to generate a global compensation mapping table; dynamically obtaining the temperature of each correction zone through a temperature sensor network, correcting the compensation matrix based on a thermal expansion coefficient model of the liquid crystal material, and updating the global compensation mapping table; inputting the updated global compensation mapping table into a storage unit of a display screen driver chip to complete the correction. This method solves the problem that existing global correction methods cannot meet production needs for ultra-large LCD displays.

Description

Technical Field

[0001] The present invention relates to the technical field of display screen correction, and in particular to a color correction system and method for an LCD display screen. Background Art

[0002] LCD screens use the electro-optical effect of liquid crystal to display images. When there is no electric field, the liquid crystal molecules will arrange themselves according to a certain pattern, causing specific polarization and refraction phenomena when light passes through. When an electric field is applied, the arrangement direction of the liquid crystal molecules changes, thereby changing the propagation path and light transmittance of the light.

[0003] During the production process, ultra-large LCD displays (with a diagonal size exceeding 86 inches) are prone to color differences in different areas due to factors such as poor backlight module uniformity and liquid crystal molecular orientation deviation. Traditional global correction methods cannot adapt to the partition characteristics and do not consider the impact of temperature.

[0004] Therefore, the present invention provides a system and method for color correction of an LCD display screen to solve the above-mentioned problems. Summary of the Invention

[0005] In view of the above situation, in order to overcome the defects of the prior art, the present invention provides a color correction system and method for an LCD display screen, which solves the problem that the existing global correction method cannot meet the production needs for ultra-large LCD displays.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] In one aspect, a method for color correction of an LCD display screen is provided, the method comprising the following steps:

[0008] S100, dividing the LCD display screen into a plurality of independent calibration zones, and obtaining display parameters of each calibration zone, wherein the display parameters include at least brightness value, chromaticity coordinates, and white balance deviation value of each calibration zone under a standard light source;

[0009] S200, constructing a color difference compensation matrix for each correction partition based on the difference between the display parameters of each correction partition and the preset standard value, and fitting the linear compensation coefficients of the RGB channels by the least squares method;

[0010] S300, using a bilinear interpolation algorithm to smooth the compensation matrices of adjacent correction partitions to generate a global compensation mapping table;

[0011] S400, dynamically obtain the temperature of each correction partition through the temperature sensor network, correct the compensation matrix based on the thermal expansion coefficient model of the liquid crystal material and update the global compensation mapping table, input the updated global compensation mapping table into the storage unit of the display driver chip to complete the correction.

[0012] A further improvement of the present application is that, in step S100, the LCD display is divided into a plurality of independent correction partitions, which should meet the following conditions: the number of correction partitions is proportional to the diagonal size of the LCD display, and the closer to the edge of the LCD display, the higher the correction partition density, and the density gradient follows the formula:

[0013]

[0014] In expression (1), D0 represents the initial partition density of the central area of ​​the LCD display, r represents the shortest distance from the current partition center point to the edge of the LCD display, and R is the equivalent radius of the LCD display.

[0015] A further improvement of the present application is that, in step S100, the white balance deviation value is the relative deviation between the measured color temperature and the target color temperature value when the LCD display screen displays a pure white picture.

[0016] A further improvement of the present application is that, after step S100, it also includes a secondary verification of the abnormal display parameters of the correction partition. The trigger condition of the secondary verification is: if the brightness standard deviation of any correction partition exceeds a preset threshold, or the chromaticity coordinates exceed the sRGB color gamut range, the automatic re-measurement process is triggered until the data meets the confidence interval requirements.

[0017] A further improvement of the present application is that, in step 200, the correction partition chromatic aberration compensation matrix C is constructed. i,j ,include:

[0018] S201: Determine the color difference ΔE of each correction partition i,j The color difference of each correction partition is calculated and determined by the CIEDE2000 formula;

[0019] S202: For each correction partition (i, j), establish an RGB driving signal (R i,j ,G i,j ,B i,j ) and color difference ΔE i,j The mapping model is expressed as:

[0020]

[0021] In expression (2), a1, a2, a3, b1, b2, b3, and c represent the parameters to be fitted;

[0022] S203, using the least squares method to solve the parameters to be fitted in the model in step S202, obtain the linear compensation coefficients of the RGB three channels, and construct a correction partition color difference compensation matrix. The expression of the correction partition color difference compensation matrix is:

[0023]

[0024] In expression (3), α i,j , γ i,j Indicates the gain coefficient of the channel, which is used to adjust the amplification ratio of the input corresponding signal, β i,j , δ i,j Indicates the offset of the channel, which is used to correct the static deviation of the corresponding component, κ i,j Indicates the white balance compensation factor, which is used to adjust the color temperature consistency of the channel.

[0025] A further improvement of the present application is that, in step S300, a bilinear interpolation algorithm is used to smooth the compensation matrices of adjacent correction partitions, including:

[0026] S301, obtain any pixel point (x, y) in any correction partition screen of the LCD display screen, and determine the compensation matrix C of the four adjacent partitions to which it belongs i,j ,C i+1,j ,C i,j+1 ,C i+1,j+1 , and according to the relative position of the pixel point (x, y) in the partition, calculate the horizontal interpolation weight and the vertical interpolation weight, and determine the compensation value of the pixel point;

[0027] S302: If the pixel point is located at the edge of the screen and has no adjacent partition, a mirror filling method is used to expand the compensation matrix;

[0028] S303 , for areas where there are still sudden gradient changes after the interpolation in steps S301 and S302 , a Gaussian filter kernel is superimposed to smooth the color scale until the sudden gradient changes remaining after the interpolation are eliminated.

[0029] A further improvement of the present application is that, in step S400, dynamically acquiring the temperature of each correction zone through a temperature sensor network and correcting the compensation matrix based on a thermal expansion coefficient model of the liquid crystal material include:

[0030] S401, obtain the temperature T of each calibration partition i,j , and build a temperature data model in which the temperature changes with time. The expression of the temperature data model is:

[0031]

[0032] In expression (4), T0 represents the initial temperature of the display screen under a stable environment; ΔT k represents the increment of the kth temperature change, τ is the thermal inertia time constant, which represents the decay rate of the temperature change, and t is the time variable, which represents the time interval from the occurrence of the temperature change to the current moment;

[0033] S402: Obtain a pre-stored liquid crystal material parameter table and adjust the compensation matrix. The expression of the adjusted compensation matrix is:

[0034]

[0035] In expression (5), C i,j represents the original compensation matrix, obtained by expression (3), ⊙ represents the Hadamard product, ΔT=T i,j -T0 represents the difference between the current temperature and the reference temperature, k R, k G, k B Indicates the temperature drift coefficient of the corresponding channel, ΔC LC (T) represents the cross compensation term caused by the change in the refractive index of the liquid crystal.

[0036] A further improvement of the present application is that, in step 402, the pre-stored liquid crystal material parameters include: a temperature drift coefficient of the RGB channels corresponding to the channels, which is used to compensate for the decrease in backlight efficiency or the response delay of the liquid crystal molecules due to the increase in temperature; a refractive index temperature coefficient of the liquid crystal material, which is used to correct the changes in the optical properties of the liquid crystal layer caused by temperature changes; and a backlight brightness attenuation factor, which is used to dynamically adjust the backlight brightness and suppress the brightness drop at high temperatures.

[0037] On the other hand, a color correction system for an LCD display screen is provided, characterized in that it includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform any of the methods described above.

[0038] The beneficial effects of the present invention are: through zoning correction and temperature compensation, precise color correction is achieved for very large LCD displays, resolving the issues of traditional global correction methods that are unable to adapt to zoning characteristics and fail to consider temperature effects. The correction method of the present invention not only improves correction accuracy, with zoning accuracy increased by 300% compared to traditional methods and a JNCD value of less than 0.5, but also adapts to temperature changes on the display in real time, suppressing thermochromic drift to within ±2% through temperature compensation, thereby ensuring the stability and consistency of the display effect. Furthermore, correction efficiency is improved, with the processing time for a single screen controlled within 10 minutes. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A schematic flow chart of a method for color correction of an LCD display screen according to the present invention;

[0040] Figure 2 The figure is a schematic structural diagram of a color correction system for an LCD display screen according to the present invention. DETAILED DESCRIPTION

[0041] The following will describe various embodiments of the present invention in detail with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0042] Ultra-large LCDs usually refer to display screens with a diagonal size exceeding 86 inches, which are mainly used in commercial, public display and high-end consumer scenarios. In the process of producing ultra-large LCD screens, the inventors found that ultra-large LCD screens are prone to color differences in different areas due to factors such as poor uniformity of the backlight module and deviation in the orientation of liquid crystal molecules. If the traditional global correction method is used, it can no longer adapt to the partition characteristics and the correction efficiency is low. In addition, the traditional global correction method does not take temperature effects into account, resulting in unsatisfactory color correction effects.

[0043] Based on the above problems, the inventors provide the following solutions:

[0044] 1. Partition acquisition: Divide the large LCD screen into multiple areas and collect display data for each area separately.

[0045] 2. Optical calibration: Use high-precision sensors to measure parameters such as brightness, chromaticity, uniformity, etc. of each area.

[0046] 3. Dynamic compensation algorithm: Based on the measurement data, the compensation coefficient of each area is calculated and the drive signal is adjusted.

[0047] 4. Temperature compensation: Considering the temperature changes when the large screen is working, a temperature sensor may be added for real-time adjustment.

[0048] 5. Store calibration parameters: Store the calibration parameters for each area in the display's firmware to ensure consistency after leaving the factory.

[0049] To address the above issues, the present application provides a method for color correction of an LCD display screen, the method comprising the following steps:

[0050] S100, dividing the LCD display screen into a plurality of independent calibration zones, and obtaining display parameters of each calibration zone, wherein the display parameters include at least brightness value, chromaticity coordinates, and white balance deviation value of each calibration zone under a standard light source;

[0051] S200, constructing a color difference compensation matrix for each correction partition based on the difference between the display parameters of each correction partition and the preset standard value, and fitting the linear compensation coefficients of the RGB channels by the least squares method;

[0052] S300, using a bilinear interpolation algorithm to smooth the compensation matrices of adjacent correction partitions to generate a global compensation mapping table;

[0053] S400, dynamically obtain the temperature of each correction partition through the temperature sensor network, correct the compensation matrix based on the thermal expansion coefficient model of the liquid crystal material and update the global compensation mapping table, input the updated global compensation mapping table into the storage unit of the display driver chip to complete the correction.

[0054] The technical solution will be described in detail below in conjunction with specific embodiments.

[0055] Example

[0056] refer to Figure 1 , a color correction method for an LCD display screen, the correction method comprising the following steps:

[0057] S100, dividing the LCD display screen into N×M independent correction partitions, and obtaining display parameters of each correction partition, wherein the display parameters at least include the brightness value L of each correction partition under a standard light source. i,j , chromaticity coordinates (x i,j ,y i,j ) and white balance deviation value ΔW i,j ;

[0058] S200: construct a color difference compensation matrix C for each correction partition based on the difference between the display parameters of each correction partition and the preset standard value. i,j , and fit the linear compensation coefficients of RGB channels by the least squares method;

[0059] S300, using a bilinear interpolation algorithm to smooth the compensation matrices of adjacent correction partitions to generate a global compensation mapping table;

[0060] S400, dynamically obtain the temperature T of each correction partition through the temperature sensor network i,j , based on the thermal expansion coefficient model of the liquid crystal material, the compensation matrix is ​​corrected and the global compensation mapping table is updated, and the updated global compensation mapping table is input into the storage unit of the display driver chip to complete the correction.

[0061] In one embodiment of the present application, in step S100, the LCD display (taking an 86-inch rectangular screen as an example) is divided into N×M (e.g., 24×36 partitions) independent correction partitions, which should meet the following conditions: the number of correction partitions N×M is proportional to the diagonal size of the LCD display, and the closer to the edge of the LCD display, the higher the correction partition density, and the density gradient follows the formula:

[0062]

[0063] In expression (1), D0 represents the initial partition density of the central area of ​​the LCD display, r represents the shortest distance from the current partition center point to the edge of the LCD display, and R is the equivalent radius of the LCD display (109.16 cm).

[0064] Through expression (1), the sparse partitioning of the central area reduces the amount of calculation, and the overall number of partitions only increases by about 30%, but the correction effect is improved by more than 50%. The gradient formula can be adapted to different screen sizes by simply adjusting D0 and R without redesigning the algorithm.

[0065] Specifically, during operation, a D65 light source that complies with the ISO3664:2009 standard is deployed in a darkroom environment as a reference lighting, the color temperature of the light source is set to 6500K±50K, the illumination uniformity is ≥95%, and the N×M partitions are scanned one by one by a multispectral imager. The spectral resolution of the multispectral imager is ≤5nm, and the spatial resolution matches the pixel density of a single partition. The brightness value of the correction partition under the standard light source is L i,j , measure the brightness of the partition center and four corner points through the photometer probe, and take the arithmetic average to obtain; chromaticity coordinates (x i,j ,y i,j ) Obtain tristimulus values ​​X through spectroradiometer i,j ,Y i,j ,Z i,j , and according to the formula: Calculated; white balance deviation value ΔW i,j When the LCD screen displays a pure white image (RGB=255,255,255), the measured color temperature T measured and color temperature target value T target The relative deviation of (6500K) is calculated as follows:

[0066] To ensure the accuracy of the data collected by each correction partition, a secondary verification of the abnormal display parameters of the correction partition is also included after step S100. The trigger condition of the secondary verification is: if the brightness standard deviation of any correction partition exceeds the preset threshold (≥10%), or the chromaticity coordinates exceed the sRGB color gamut, the automatic re-test process is triggered until the data meets the confidence interval requirements.

[0067] In one embodiment of the present application, in step 200, the correction partition chromatic aberration compensation matrix C is constructed. i,j ,include:

[0068] S201: Determine the color difference ΔE of each correction partition i,j The color difference of each correction partition is calculated and determined by the CIEDE2000 formula;

[0069] S202: For each correction partition (i, j), establish the RGB drive signal (R i,j ,G i,j ,B i,j ) and color difference ΔE i,j The mapping model is expressed as:

[0070]

[0071] In expression (2), a1, a2, a3, b1, b2, b3, and c represent the parameters to be fitted;

[0072] S203, using the least squares method to solve the parameters to be fitted in the model in step S202, obtain the linear compensation coefficients of the RGB three channels, and construct a correction partition color difference compensation matrix. The expression of the correction partition color difference compensation matrix is:

[0073]

[0074] In expression (3), α i,j , γ i,j Indicates the gain coefficient of the channel, which is used to adjust the amplification ratio of the input corresponding signal, β i,j , δ i,j Indicates the offset of the channel, which is used to correct the static deviation of the corresponding component, κ i,j Indicates the white balance compensation factor, which is used to adjust the color temperature consistency of the channel.

[0075] In step S203, κ i,j The value of ΔW i,j Determined by linear difference, the calculation formula is as follows: Where ΔW max The maximum allowable white balance deviation is preset.

[0076] In one embodiment of the present application, since the compensation matrix mentioned in step S200 is specific to each partition, each partition may have different correction parameters. However, the display screen is a continuous display area. If the compensation parameters of each partition are directly applied to the boundaries between the partitions, obvious color or brightness abrupt changes may occur, resulting in visual discontinuities such as color blocks or light and dark bands. In this case, it is necessary to smoothly transition the parameters of adjacent partitions to avoid such abrupt changes.

[0077] Preferably, in step S300, a bilinear interpolation algorithm is used to smooth the compensation matrices of adjacent correction partitions, including:

[0078] S301, obtain any pixel point (x, y) in any correction partition screen of the LCD display screen, and determine the compensation matrix C of the four adjacent partitions to which it belongsi,j ,C i+1,j ,C i,j+1 ,C i+1,j+1 ,in, And according to the relative position of the pixel point (x, y) in the partition, calculate the horizontal interpolation weight u and the vertical interpolation weight v, where u = xi, v = yj (0 ≤ u, v < 1), and determine the compensation value C (x, y) of the pixel point. The compensation value C (x, y) is obtained by the following expression:

[0079] C(x,y)=(1-u)(1-v)C i,j +u(1-v)C i+1,j +(1-u)vC i,j+1 +uvC i+1,j+1 ,;

[0080] S302: If the pixel is located at the edge of the screen and has no adjacent partitions, the compensation matrix is ​​expanded using the mirror filling method. The formula is: C N+1,j =C N-1,j ,C i,M+1 =C i,M-1 ;

[0081] S303 , for areas where there are still sudden gradient changes after interpolation in steps S301 and S302 , a Gaussian filter kernel (σ=0.5) is superimposed to smooth the color scale until the sudden gradient changes remaining after interpolation are eliminated.

[0082] Through steps S301-S303, mathematical formulas are used to clearly define the weight calculation and matrix operation rules for bilinear interpolation, ensuring a smooth transition of compensation values. Mirror padding and Gaussian filtering are introduced to avoid color discontinuities at the edges of the screen due to missing data.

[0083] In one embodiment of the present application, the refractive index of the liquid crystal material and the backlight brightness of the LCD screen may change at different temperatures, resulting in color difference. Therefore, temperature compensation needs to adjust the compensation parameters according to the real-time temperature to offset the influence of temperature on the display effect. Based on the above embodiment, in step S400, the temperature T of each correction zone is dynamically obtained through the temperature sensor network. i,j , based on the thermal expansion coefficient model of the liquid crystal material, the compensation matrix is ​​corrected, including:

[0084] S401, obtain the temperature T of each calibration partition i,j , and build a temperature data model in which the temperature changes with time. The expression of the temperature data model is:

[0085]

[0086] In expression (4), T0 represents the initial temperature of the display screen under a stable environment; ΔT k represents the increment of the kth temperature change, τ is the thermal inertia time constant (unit: second), which represents the decay rate of temperature change, and t is the time variable (unit: second), which represents the time interval from the occurrence of temperature change to the current moment;

[0087] In the actual test, an array of PT1000 thin film temperature sensors is evenly arranged on the back panel of the LCD screen, with a sensor spacing of ≤5cm, ensuring that each calibration zone contains at least one sensor; and a multiplexer is used to collect the temperature T of each zone in real time at a sampling rate of 100Hz. i,j ; Typically, T0 is set to 25°C. Specifically, when the display is in stable operation and no-load state (such as standing for 30 minutes after initial startup), the temperature at multiple time points is measured by the temperature sensor array, and the average value is taken as the reference temperature; τ is set to 10 seconds. Specifically, a known thermal disturbance is applied to the display (such as turning on the backlight to maximum brightness), and the temperature drop curve over time is recorded; an exponential decay model T(t) = T0 + ΔT·e is used. -t / τ , fit the data, and solve for τ.

[0088] S402: Obtain a pre-stored liquid crystal material parameter table and adjust the compensation matrix. The expression of the adjusted compensation matrix is:

[0089]

[0090] In expression (5), C i,j represents the original compensation matrix, obtained by expression (3), ⊙ represents the Hadamard product, ΔT=T i,j -T0 represents the difference between the current temperature and the reference temperature, k R, k G, k B Indicates the temperature drift coefficient of the corresponding channel, ΔC LC (T) represents the cross compensation term caused by the change in the refractive index of the liquid crystal.

[0091] Specifically, ΔC LC (T)Pass get;

[0092] Preferably, in step 402, the pre-stored liquid crystal material parameters include:

[0093] The temperature drift coefficient of the RGB channel corresponding to the channel, that is, k R, k G, k B(Unit: % / °C) is used to compensate for the decrease in backlight efficiency or liquid crystal molecule response delay caused by temperature increase. It indicates the ratio by which the gain of the corresponding color channel needs to be adjusted for every 1°C increase in temperature.

[0094] In specific operation, in a temperature-controlled box, the display temperature is gradually increased from T0 to the maximum threshold (such as 50°C), the RGB channel brightness values ​​at each temperature point are recorded, and linear regression analysis is used to calculate the slope of the gain change with temperature, that is, the temperature drift coefficient.

[0095] The refractive index temperature coefficient of the liquid crystal material, that is, (unit: 1 / °C), used to correct for changes in the optical properties of the liquid crystal layer caused by temperature changes (such as color shift). It represents the rate at which the refractive index changes with temperature. For example, a change in the refractive index will change the light transmittance.

[0096] Specifically, the refractive index n(T) of the liquid crystal material at different temperatures was measured using an ellipsometer, and a linear relationship was fitted.

[0097] and backlight brightness attenuation factor α BL (Unit: 1 / °C) indicates the attenuation rate of backlight brightness as temperature increases. It is used to dynamically adjust backlight brightness and suppress brightness drop at high temperatures.

[0098] Specifically, under a constant driving current, the output brightness L(T) of the backlight module at different temperatures (such as 20°C-60°C) is measured, and an exponential decay model is fitted. Solving for α BL .

[0099] Compared with the existing technology, the LCD display color correction method of this application significantly improves the correction accuracy and display effect by comprehensively considering multiple aspects such as partition correction, color difference compensation, smoothing processing and temperature compensation. In the partition correction stage, a sparse partitioning strategy of the central area is adopted to effectively reduce the amount of calculation while ensuring a significant improvement in the correction effect. The construction of the color difference compensation matrix is ​​based on the precise measurement and model fitting of the color difference of each correction partition, realizing the precise mapping between the RGB drive signal and the color difference.

[0100] Furthermore, a bilinear interpolation algorithm is used to smooth the compensation matrices of adjacent correction partitions, effectively avoiding sudden changes in color or brightness and ensuring visual continuity. Furthermore, a mirror filling method is used to expand the compensation matrix for the edge areas of the screen. In areas where gradient changes still occur after interpolation, a Gaussian filter kernel is superimposed to smooth the color scale, further improving the correction effect.

[0101] In terms of temperature compensation, this application dynamically acquires the temperature of each calibration zone through a temperature sensor network and modifies the compensation matrix based on the thermal expansion coefficient model of the liquid crystal material, effectively offsetting the impact of temperature on the display. This improves the adaptability of the calibration system and ensures excellent display quality in different temperature environments.

[0102] In summary, the LCD display color correction method of the present application has significant advantages such as high correction accuracy, excellent display effect, and strong adaptability, and provides a new solution for color correction of LCD displays.

[0103] refer to Figure 2 , a color correction system for an LCD display screen, comprising:

[0104] at least one processor;

[0105] and a memory communicatively connected to the at least one processor; wherein,

[0106] The memory stores instructions that can be executed by the at least one processor. The instructions are executed by the at least one processor to enable the at least one processor to perform the method described in the above embodiment.

[0107] Various embodiments of the systems and techniques described herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), system-on-chip systems (SOCs), programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments can include being implemented in one or more computer programs that are executable and / or interpreted on a programmable system that includes at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0108] The program code for implementing the method of the present disclosure can be written in any combination of one or more programming languages. These program codes can be provided to a processor or controller of a general-purpose computer, a special-purpose computer, or other programmable data processing device so that when the program code is executed by the processor or controller, the functions / operations specified in the flow chart and / or block diagram are implemented. The program code can be executed entirely on the machine, partially on the machine, as a stand-alone software package, partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0109] In the context of the present disclosure, a machine-readable medium can be a tangible medium that can contain or store a program for use by or in conjunction with an instruction execution system, device or equipment. A machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium can include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or equipment, or any suitable combination of the foregoing. A more specific example of a machine-readable storage medium can include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0110] To provide interaction with a user, the systems and techniques described herein can be implemented on a computer having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user can provide input to the computer. Other types of devices can also be used to provide interaction with the user; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including acoustic input, voice input, or tactile input).

[0111] The systems and techniques described herein can be implemented in a computing system that includes back-end components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes front-end components (e.g., a user computer having a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such back-end components, middleware components, or front-end components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include a local area network (LAN), a wide area network (WAN), and the Internet.

[0112] A computer system may include a client and a server. The client and server are generally remote from each other and typically interact through a communication network. The client-server relationship arises through computer programs running on the respective computers and having a client-server relationship with each other. The server may be a cloud server, a server in a distributed system, or a server integrated with a blockchain.

[0113] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this disclosure can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solutions disclosed in this disclosure can be achieved. This is not a limitation herein.

[0114] The above specific embodiments do not constitute a limitation on the scope of protection of this disclosure. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this disclosure shall be included within the scope of protection of this disclosure.

Claims

1. A method for color correction of an LCD display screen, characterized in that: The calibration method comprises the following steps: S100, dividing the LCD display screen into a plurality of independent calibration zones, and obtaining display parameters of each calibration zone, wherein the display parameters include at least brightness value, chromaticity coordinates, and white balance deviation value of each calibration zone under a standard light source; S200, constructing a color difference compensation matrix for each correction partition based on the difference between the display parameters of each correction partition and the preset standard value, and fitting the linear compensation coefficients of the RGB channels by the least squares method; S300, using a bilinear interpolation algorithm to smooth the compensation matrices of adjacent correction partitions to generate a global compensation mapping table; S400, dynamically acquiring the temperature of each correction zone through a temperature sensor network, correcting the compensation matrix based on a thermal expansion coefficient model of the liquid crystal material, and updating a global compensation mapping table, inputting the updated global compensation mapping table into a storage unit of a display driver chip to complete the correction; In step S400, the temperature of each correction zone is dynamically acquired through a temperature sensor network, and the compensation matrix is ​​corrected based on a thermal expansion coefficient model of the liquid crystal material, including: S401, obtain the temperature T of each calibration partition i,j , and build a temperature data model in which the temperature changes with time. The expression of the temperature data model is: In expression (4), T0 represents the initial temperature of the display screen under a stable environment; ΔT k represents the increment of the kth temperature change, τ is the thermal inertia time constant, which represents the decay rate of the temperature change, and t is the time variable, which represents the time interval from the occurrence of the temperature change to the current moment; S402: Obtain a pre-stored liquid crystal material parameter table and adjust the compensation matrix. The expression of the adjusted compensation matrix is: In expression (5), C i,j represents the original compensation matrix, obtained by expression (3), ⊙ represents the Hadamard product, ΔT=T i,j -T0 represents the difference between the current temperature and the reference temperature, k R ,k G ,k B Indicates the temperature drift coefficient of the corresponding channel, ΔC LC (T) represents the cross compensation term caused by the change in the refractive index of the liquid crystal.

2. The method for color correction of an LCD display screen according to claim 1, wherein: In step S100, the LCD display screen is divided into a number of independent correction zones, which should meet the following conditions: the number of correction zones is proportional to the diagonal size of the LCD display screen, and the closer to the edge of the LCD display screen, the higher the correction zone density, and the density gradient follows the formula: In expression (1), D0 represents the initial partition density of the central area of ​​the LCD display, r represents the shortest distance from the current partition center point to the edge of the LCD display, and R is the equivalent radius of the LCD display.

3. The method for color correction of an LCD display screen according to claim 1, wherein: In step S100 , the white balance deviation value is the relative deviation between the measured color temperature and the target color temperature value when the LCD display screen displays a pure white image.

4. The method for color correction of an LCD display screen according to claim 1, wherein: After step S100, a secondary verification of the abnormal display parameters of the correction partition is also included. The trigger condition of the secondary verification is: if the brightness standard deviation of any correction partition exceeds the preset threshold, or the chromaticity coordinates exceed the sRGB color gamut range, the automatic re-test process is triggered until the data meets the confidence interval requirements.

5. The method for color correction of an LCD display screen according to claim 1, wherein: In step 200, the correction partition chromatic aberration compensation matrix C is constructed. i,j ,include: S201: Determine the color difference ΔE of each correction partition i,j The color difference of each correction partition is calculated and determined by the CIEDE2000 formula; S202: For each correction partition (i, j), establish an RGB driving signal (R i,j ,G i,j ,B i,j ) and color difference ΔE i,j The mapping model is expressed as: In expression (2), a1, a2, a3, b1, b2, b3, and c represent the parameters to be fitted; S203, using the least squares method to solve the parameters to be fitted in the model in step S202, obtain the linear compensation coefficients of the RGB three channels, and construct a correction partition color difference compensation matrix. The expression of the correction partition color difference compensation matrix is: In expression (3), α i,j , γ i,j Indicates the gain coefficient of the channel, which is used to adjust the amplification ratio of the input corresponding signal, β i,j , δ i,j Indicates the offset of the channel, which is used to correct the static deviation of the corresponding component, κ i,j Indicates the white balance compensation factor, which is used to adjust the color temperature consistency of the channel.

6. The method for color correction of an LCD display screen according to claim 5, wherein: In step S300, a bilinear interpolation algorithm is used to smooth the compensation matrices of adjacent correction partitions, including: S301, obtain any pixel point (x, y) in any correction partition screen of the LCD display screen, and determine the compensation matrix C of the four adjacent partitions to which it belongs i,j ,C i+1,j ,C i,j+1 ,C i+1,j+1 , and according to the relative position of the pixel point (x, y) in the partition, calculate the horizontal interpolation weight and the vertical interpolation weight, and determine the compensation value of the pixel point; S302: If the pixel point is located at the edge of the screen and has no adjacent partition, a mirror filling method is used to expand the compensation matrix; S303 , for areas where there are still sudden gradient changes after the interpolation in steps S301 and S302 , a Gaussian filter kernel is superimposed to smooth the color scale until the sudden gradient changes remaining after the interpolation are eliminated.

7. The method for color correction of an LCD display screen according to claim 1, wherein: In step 402, the pre-stored liquid crystal material parameters include: The temperature drift coefficient of the corresponding RGB channels is used to compensate for the decrease in backlight efficiency or the response delay of liquid crystal molecules caused by temperature increase; The temperature coefficient of the refractive index of the liquid crystal material is used to correct the changes in the optical properties of the liquid crystal layer caused by temperature changes; and backlight brightness attenuation factor, which are used to dynamically adjust the backlight brightness and suppress the brightness drop at high temperatures.

8. A color correction system for an LCD display screen, characterized in that: include: at least one processor; and a memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method according to any one of claims 1 to 7.

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