A display screen color management and correction method

Abstract

The application relates to the technical field of display screen color management, in particular to a display screen color management and correction method, which comprises the following steps: collecting measured white point coordinates in a display frame blanking period, combining reference white point coordinates and cumulative lighting time weight to calculate global chroma offset and reserve independent offset vectors; calculating color difference based on the global chroma offset, screening nodes to be corrected according to color difference uniformity specification parameters and updating according to priority; constructing a full-screen continuous offset field based on the independent offset vectors, combining backlight partition space boundaries to calculate local chroma compensation vectors, solving the minimum norm solution to obtain a driving current fine adjustment amount and superimposing the driving current fine adjustment amount to reference driving parameters; recording color difference to calculate color difference growth rate, and adaptively calculating a trigger waiting time in combination with a safety margin coefficient. The application fundamentally suppresses the problem of irreversible deterioration of chroma with use time.

Description

Technical Field

[0001] This application relates to the field of display screen color management technology, specifically to a display screen color management and calibration method. Background Technology

[0002] LCD technology is widely used in smart home image display terminals, especially in high-quality consumer-grade display devices such as smart photo frames. As consumers' demands for image presentation accuracy continue to rise, wide color gamut LCD modules are gradually becoming the mainstream solution in the industry. Their color gamut coverage has expanded from the traditional sRGB standard to DCI-P3 and even wider color spaces. To meet professional-grade color reproduction requirements, display modules generally incorporate color calibration processes at the factory. This involves mapping and correcting the color output of the LCD panel using a pre-set three-dimensional lookup table to compensate for color shift issues caused by individual differences in panel components.

[0003] Within the factory calibration framework, existing technologies further incorporate environmental adaptive adjustment methods. These methods utilize ambient light sensors to collect external illuminance data, and then perform coarse compensation on display brightness and color temperature during operation. To address the presentation requirements of HDR content, existing image quality engines also integrate a tone mapping module, which coordinates and adjusts backlight drive gain and liquid crystal transmittance based on the global brightness histogram of the input image.

[0004] However, existing color management methods suffer from a fundamental flaw systematically overlooked in actual display conditions: the factory-preset 3D lookup table is a static data table generated in a standardized measurement environment based on the panel's initial state. During long-term operation, the spectral power distribution of the backlight source continuously drifts due to accumulated drive current and increased junction temperature. Simultaneously, the aging rates of different backlight zones within the panel vary significantly due to uneven local brightness usage, resulting in a non-uniform drift in the overall color temperature distribution. The combined effect of these two types of drifts means that the color mapping described by the static 3D lookup table is severely mismatched with the actual spectral state of the current panel, causing irreversible degradation in color accuracy over time, ultimately leading to display output colorimetry exceeding the requirements for professional-grade color consistency. Summary of the Invention

[0005] To address the existing technical problem of mismatch between the static three-dimensional lookup table and the actual spectral state of the panel due to long-term backlight spectrum drift in liquid crystal display panels, and the continuous deviation of color from the target value during operation, this application provides a display color management and calibration method.

[0006] This application provides a display screen color management and calibration method, including: driving the backlight partition to output a standard white field excitation signal during the blanking period of the display frame, simultaneously acquiring the measured white point coordinates of multiple sampling points, combining the reference white point coordinates and the cumulative illumination duration weight of the backlight partition corresponding to each sampling point, calculating the global chromaticity offset, and retaining the independent offset vector of each sampling point; calculating the color difference between the expected chromaticity coordinates and the corrected target chromaticity coordinates corresponding to the output node in the three-dimensional lookup table based on the global chromaticity offset, and selecting the nodes to be corrected according to the preset color difference uniformity specification parameters, and updating the nodes to be corrected according to the preset priority order; constructing a full-screen continuous offset field by interpolation expansion based on the independent offset vector, calculating the local chromaticity compensation vector in combination with the spatial boundary of the backlight partition, and solving the minimum norm solution based on the preset color characteristic matrix to obtain the driving current fine-tuning amount of each backlight partition sub-channel and superimposing it on the reference driving parameters; recording the color difference in the historical calibration cycle to calculate the color difference growth rate, and adaptively calculating the trigger waiting time for the next calibration in combination with the safety margin coefficient determined based on the panel factory parameters, so as to update the calibration trigger cycle.

[0007] By dynamically updating the online colorimetric data and 3D lookup table nodes during the blanking period, the color correction system is transformed from a one-time factory calibration to a tracking process that is continuously bound to the actual spectral state of the panel, significantly extending the effective working time for maintaining the display colorimetric data within the professional-grade specification range.

[0008] Preferably, the global chromaticity offset is calculated by combining the reference white point coordinates and the cumulative illumination duration weight of the backlight partition corresponding to each sampling point. This includes: performing a difference operation between the measured white point coordinates and the reference white point coordinates to obtain the chromaticity offset vector of each sampling point; obtaining the historical data of the partition duty cycle collected in real time by the backlight control module, and integrating it to obtain the cumulative illumination duration of the backlight partition corresponding to each sampling point; calculating the ratio of the cumulative illumination duration to the total illumination duration of the entire screen to determine the weight of each sampling point; and using the weight of each sampling point to calculate the weighted average of the chromaticity offset vector to finally obtain the global chromaticity offset.

[0009] By calculating the weighted average of the cumulative lighting duration, the global offset more accurately reflects the combined effect of the aging differences in each partition, effectively avoiding the representativeness bias caused by the simple arithmetic mean ignoring the differences in the intensity of use in each partition.

[0010] Preferably, nodes to be corrected are selected based on preset color difference uniformity specifications, and updates are performed on the nodes to be corrected according to preset priority order, including: comparing the calculated color difference with the color difference uniformity specifications used as the selection threshold; marking nodes with color differences exceeding the selection threshold as nodes to be corrected and adding them to the update queue; determining the priority order from the vicinity of the neutral gray axis at the center of the three-dimensional lookup table space to the high saturation vertices on the periphery; processing the nodes to be corrected in the update queue in batches according to the priority order, and finally completing the update of the nodes to be corrected.

[0011] Preferably, a full-screen continuous offset field is constructed based on independent offset vectors through interpolation expansion, and a local chromaticity compensation vector is calculated in combination with the spatial boundary of the backlight partition. This includes: using the screen physical coordinates of multiple sampling points as control points, using bilinear interpolation to expand the discrete independent offset vectors into a full-screen continuous offset field covering the entire screen; superimposing and matching the full-screen continuous offset field with the spatial boundary of each backlight partition; calculating the regional mean of the offset field within the range of each backlight partition, and finally obtaining the local chromaticity compensation vector of that partition.

[0012] Preferably, the minimum norm solution is obtained based on a preset color characteristic matrix to obtain the driving current fine-tuning amount of each backlight zone sub-channel and superimposed on the reference driving parameters. This includes: obtaining a color characteristic matrix describing the linear approximate relationship between the driving current change and the chromaticity coordinate change; obtaining the generalized inverse of the color characteristic matrix and combining it with the local chromaticity compensation vector to obtain the minimum norm solution; using the minimum norm solution as the driving current fine-tuning amount of each backlight zone sub-channel; and superimposing the driving current fine-tuning amount on the reference driving parameters of the current backlight zone, ultimately achieving independent compensation for the local color temperature deviation of each zone.

[0013] By combining the interpolation of the partition offset field with the solution of the minimum norm of the color characteristic matrix, independent compensation is applied to the local color temperature deviation caused by the difference in aging degree in each backlight partition, so as to significantly improve the uniformity of the color temperature distribution of the whole screen.

[0014] Preferably, recording color differences within historical calibration cycles to calculate the color difference growth rate includes: maintaining a sliding window to record the color differences detected in multiple consecutive calibrations in the past; obtaining the time interval between each calibration and the last calibration; and calculating the average based on the ratio of color difference to time interval to finally obtain the color difference growth rate per unit time.

[0015] Preferably, maintaining a sliding window includes: continuously executing multiple correction cycles and recording the offset sequence for each cycle during the initial operation phase of the device; calculating the autocorrelation function of the offset sequence; extracting the lag step number corresponding to the first decay of the autocorrelation coefficient to below a preset threshold; using the lag step number as the initial value to determine the window length, and finally establishing the sliding window.

[0016] Preferably, the trigger waiting time for the next correction is adaptively calculated by combining the safety margin coefficient determined based on the panel's factory parameters, including: reading the panel's initial aging rate and the maximum allowable drift rate at the end of the rated life recorded in the panel's factory report; calculating the ratio of the panel's initial aging rate to the maximum drift rate to determine the safety margin coefficient; and dividing the color difference uniformity specification parameter by the product of the color difference growth rate and the safety margin coefficient to calculate the trigger waiting time for the next correction.

[0017] By using an adaptive triggering method that employs drift rate sliding estimation and safety margin pre-intervention, the triggering frequency is automatically sparse in the early stages of panel aging, and the triggering interval is automatically narrowed in the accelerated aging stage, thus achieving a dynamic balance between correction timeliness and system resource consumption.

[0018] Preferably, during the blanking period of the display frame, the backlight partition is driven to output a standard white field excitation signal, and the measured white point coordinates of multiple sampling points are collected simultaneously. This includes: outside the normal screen refresh process of the display module, the blanking period of the display frame is used as a measurement time window; within the measurement time window, each backlight partition is driven to output a standard white field excitation signal in sequence, so that the panel presents a full white state; using a miniature color sensor array built into the module bezel, the sampling points in the central area and four corners of the screen are collected simultaneously, and finally the measured white point coordinates at the current moment are obtained.

[0019] Preferably, the calculation of the color difference between the expected chromaticity coordinates and the corrected target chromaticity coordinates of the output nodes in the 3D lookup table based on the global chromaticity offset includes: obtaining the expected chromaticity coordinates corresponding to each output node in the current 3D lookup table using a uniform color space as a basis; correcting the expected chromaticity coordinates using the global chromaticity offset to obtain the corrected target chromaticity coordinates; and finally calculating the color difference based on the expected chromaticity coordinates and the corrected target chromaticity coordinates, combined with the lightness value of the corresponding brightness level of the node.

[0020] The present invention has the following beneficial effects:

[0021] This invention achieves accurate extraction of the global offset benchmark of the panel's actual spectral state by performing interference-free chromaticity acquisition during the display frame blanking period and weighting the calculation based on the cumulative illumination duration of the backlight zones. Furthermore, by using color difference uniformity specifications to filter and prioritize nodes in the three-dimensional lookup table, computational resources are concentrated on the most visually sensitive areas, effectively improving the efficiency and targeting of color correction and ensuring the color reproduction accuracy of the display device during long-term use.

[0022] Furthermore, this invention addresses the issue of spatially non-uniform color temperature caused by differences in aging rates across different areas of the panel. By constructing a continuous offset field across the entire screen and combining it with a color characteristic matrix to solve for the minimum norm, it achieves independent and balanced fine-tuning of the driving current for each backlight zone, significantly improving the uniformity of the color temperature across the entire screen. Simultaneously, an adaptive triggering method based on the color difference growth rate and a safety margin coefficient is introduced, enabling the calibration cycle to be dynamically adjusted according to the panel aging process. This rationally allocates system resources while ensuring color accuracy, extending the high-quality working life of the display module. Attached Figure Description

[0023] Figure 1 This is a flowchart of a display screen color management and calibration method; Figure 2 It is a grouped clustered columnar comparison chart of the color offset of each backlight zone before and after correction. Detailed Implementation

[0024] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments.

[0025] This invention discloses a method for color management and calibration of a display screen, referring to... Figure 1 This includes steps S1-S4: S1. Collect the measured coordinates of the white point and calculate the global chromaticity offset.

[0026] Outside of the normal screen refresh cycle, the display module uses the blanking period of the display frame as a measurement time window, driving each backlight zone to sequentially output standard white field excitation signals, making the panel appear completely white. During the blanking period, the LCD panel is in a non-refreshing state, and the user is unaware of this measurement process. The entire acquisition operation does not cause any visible interference to the normal display frame. A miniature colorimetric sensor array built into the module bezel measures the colorimetric coordinates of five sampling points—the central area and four corners of the screen—within this window. Perform synchronous data acquisition to obtain the set of measured white point coordinates at the current moment. ,in The sampling point number, .

[0027] Compare the measured white point coordinates with the reference white point coordinates recorded during factory calibration. Perform interpolation to obtain the chromaticity offset vector for each sampling point:

[0028] Furthermore, historical data on the duty cycle of each backlight zone, collected in real-time from the backlight control module, are obtained, and the cumulative illumination time of the corresponding backlight zone at each sampling point is calculated by integrating the data. The ratio of the cumulative illumination time to the total illumination time of the entire screen is then calculated to determine the weight of each sampling point. Weight of each sampling point The calculation formula is:

[0029] in For the first The cumulative illumination time of the backlight zone to which the sampling point belongs. Since a longer local illumination time results in more accumulated driving current and deeper aging of the backlight source, its spectral drift contributes more significantly to the overall white point offset. Therefore, assigning a higher weight to this zone allows the global offset to more accurately reflect the combined effect of aging differences across zones. The weighted average of the chromaticity offset vector is calculated using the weights of each sampling point to obtain the final global chromaticity offset. The weighted average calculation formula is:

[0030] At the same time, while outputting the global chroma offset, the system fully preserves the independent offset vector of each sampling point. This allows for direct use in subsequent partition-level compensation steps, avoiding redundant data collection.

[0031] Thus, by using non-disruptive online measurements during the blanking period and calculating the difference weighted by the degree of aging, the system objectively extracts the global chromaticity shift of the panel's current actual spectral state relative to the factory reference. This provides a global benchmark input that is strongly tied to the actual aging differences of each backlight zone, for subsequent three-dimensional lookup table correction.

[0032] S2. Calculate the color difference and filter the nodes to be corrected before performing the update.

[0033] Get global chromaticity offset Then, it is transformed into a correction of the node coordinates of the 3D lookup table. The 3D lookup table uses RGB input code values ​​as 3D indices and the target display chromaticity driving code values ​​as outputs, with nodes distributed in a uniform or non-uniform grid. Since the computational cost of recalculating all nodes indiscriminately is too large, this step focuses on prioritizing the updating of the subset of nodes most sensitive to chromaticity shifts.

[0034] Specifically, using the CIE1976 uniform color space as a basis, the expected chromaticity coordinates corresponding to each output node in the current three-dimensional lookup table are obtained. The target chromaticity coordinates are obtained by correcting the expected chromaticity coordinates using a global chromaticity offset. Based on the expected chromaticity coordinates and the corrected target chromaticity coordinates, combined with the lightness value of the corresponding brightness level of the node, the color difference is finally calculated. The CIELUV color difference formula is used:

[0035] in This represents the brightness value corresponding to the brightness level of that node. and Take the global chromaticity offset components respectively and The calculated color difference is compared with a preset color difference uniformity specification parameter used as a screening threshold. The comparison is performed; this value is directly read from the panel's factory calibration report and is an objectively known quantity strongly tied to the specific panel product specifications. Nodes with color differences exceeding the screening threshold are marked as nodes to be corrected and added to the update queue; nodes that do not exceed the threshold retain their current values.

[0036] Furthermore, a preset priority order is determined from the vicinity of the neutral gray axis at the center of the 3D lookup table space outwards towards the high-saturation vertices. The nodes to be corrected in the update queue are processed batch by batch according to the preset priority order, ultimately completing the update of the nodes to be corrected. Since the display content corresponding to the nodes near the neutral gray axis is precisely the neutral tone region where the human eye is most sensitive to white point shifts, prioritizing correction can achieve the most significant visual improvement effect in the shortest computation time.

[0037] In this way, by using color difference threshold filtering and gray axis priority in batch updates, the system only recalculates the nodes to be corrected within a single correction cycle, compressing the computational overhead of the online update operation of the 3D lookup table to a reasonable range.

[0038] S3. Construct the offset field, solve for the fine-tuning amount, and superimpose it onto the baseline parameters.

[0039] Global chromaticity offset correction can handle uniform drift across the entire screen, but it cannot cover the spatially non-uniform color temperature distribution caused by differences in the aging rates of different backlight zones, which can only be addressed by a single global offset. To address this spatial non-uniformity, this step utilizes independent offset vectors retained during the acquisition phase. Establish a zone-level compensation layer.

[0040] Using the screen physical coordinates of multiple sampling points as control points, bilinear interpolation is employed to extend discrete, independent offset vectors into a continuous full-screen offset field covering the entire screen. ,in For the physical coordinates of any pixel on the screen. This represents the continuous offset field across the entire screen. By superimposing and matching the spatial boundaries of each backlight zone, the regional mean of the offset field within the range of each backlight zone is calculated, and finally the local chromaticity compensation vector of that zone is obtained. ,in This is the backlight zone number.

[0041] Next, in the backlight driving layer, a color characteristic matrix describing the linear approximate relationship between the change in driving current and the change in chromaticity coordinates is obtained. The matrix is ​​2×3 dimensional:

[0042] Since the above equations are an underdetermined system of equations, there are infinitely many solutions that satisfy the constraints. To determine the unique optimal solution, we need to find the Moore-Penrose generalized inverse of the color characteristic matrix. And combine the local chromaticity compensation vector to solve for the minimum norm solution:

[0043] The minimum norm solution is used as the fine-tuning amount of the drive current for each backlight zone sub-channel. This minimum norm solution, among all drive current adjustment combinations that satisfy the chroma compensation constraint, makes... To achieve the minimum value, the adjustment range of the drive current of each sub-channel is optimally balanced while meeting the compensation requirements. Known from the manufacturer It was calculated offline.

[0044] The fine-tuning of the drive current is superimposed on the reference drive parameters of the current backlight zone, ultimately achieving independent compensation for the local color temperature deviation of each zone.

[0045] Thus, through the combined processing of offset field interpolation extension and minimum norm current solution, the system can accurately and independently compensate for the local color temperature deviation of each backlight zone in the whole screen, eliminating the spatial non-uniform color temperature distribution accumulated due to the difference in the intensity of use of each zone.

[0046] S4. Calculate the color difference growth rate and update the correction trigger cycle.

[0047] The aforementioned chromaticity acquisition, lookup table correction, and partition current compensation together constitute a complete color correction execution chain. Determining the trigger frequency directly affects the timeliness of correction and the rational allocation of system power consumption. Therefore, the system constructs an adaptive trigger timer based on the cumulative color difference rate.

[0048] Maintain a sliding window to record past consecutive correction periods. Color difference detected by secondary calibration The time interval between each correction and the last correction is obtained. The average value is calculated based on the ratio of color difference to time interval, and finally the color difference growth rate per unit time is obtained:

[0049] in For the first The time interval between the next calibration and the previous calibration, in hours. The sliding window length is determined based on the number of autocorrelation lag steps of the offset sequence; for example, The value can be 10. This reflects the spectral drift rate at which the panel is currently in the aging stage.

[0050] Furthermore, during the initial operation phase of the equipment, multiple calibration cycles are executed consecutively, and the offset sequence for each cycle is recorded. The autocorrelation function of the offset sequence is calculated. The lag step count corresponding to the first decay of the autocorrelation coefficient below a preset threshold is extracted. The lag step count is used as the initial value to determine the window length. Finally, a sliding window is established. Using this step size as the window length ensures that the samples within the window fully cover the memory span of the drift process.

[0051] Next, based on the safety margin coefficient determined by the panel's factory parameters, the trigger waiting time for the next calibration is adaptively calculated. Read the initial aging rate of the panel recorded in the panel's factory report. Maximum drift rate allowed at the end of rated life Calculate the ratio of the initial aging rate to the maximum drift rate of the panel to determine the safety margin factor. :

[0052] Divide the color difference uniformity specification parameter by the product of the color difference growth rate and the safety margin factor to calculate the trigger wait time for the next correction:

[0053] Compared to basic calculations that do not incorporate a safety margin factor, the above formula advances the triggering time to before the color difference reaches the tolerance boundary, intervening early with the inverse of the safety margin factor to ensure that the displayed color is always constrained within the specification range. The trigger waiting time is obtained through the above calculation to update and correct the trigger cycle.

[0054] Thus, by using an adaptive triggering method based on drift rate sliding estimation and safety margin pre-intervention, the system achieves a dynamic balance between timely correction and system resource usage as the aging process progresses.

[0055] Reference Figure 2 The horizontal axis represents the backlight zones, which are divided into five zones, corresponding to high-frequency, mid-frequency, and low-frequency usage scenarios, respectively; the vertical axis represents the chromaticity offset. Figure 2In the graph, existing methods are represented by diagonally filled bars, while the present invention's method is represented by solid-filled bars. These two types of bars are arranged side-by-side to form a grouped clustered bar chart. It can be observed that in each frequency usage zone, the chromaticity shift of existing methods is significantly higher than that of the present invention, especially in high-frequency usage zones, indicating that the present invention's method achieves effective chromaticity shift suppression in all zones.

[0056] In the description of this specification, "multiple" or "several" means at least two, such as two, three or more, unless otherwise expressly and specifically defined.

Claims

1. A method for color management and calibration of a display screen, characterized in that, include: During the blanking period of the display frame, the backlight partition is driven to output the standard white field excitation signal, and the measured white point coordinates of multiple sampling points are collected simultaneously. The global chromaticity offset is calculated by combining the reference white point coordinates and the cumulative lighting duration weight of the backlight partition corresponding to each sampling point, and the independent offset vector of each sampling point is retained. The color difference between the expected chromaticity coordinates and the corrected target chromaticity coordinates of the output nodes in the three-dimensional lookup table is calculated based on the global chromaticity offset. The nodes to be corrected are selected according to the preset color difference uniformity specification parameters, and the nodes to be corrected are updated according to the preset priority order. Based on the independent offset vector, a full-screen continuous offset field is constructed by interpolation expansion. The local chromaticity compensation vector is calculated by combining the spatial boundary of the backlight partition. The minimum norm solution is solved based on the preset color characteristic matrix to obtain the driving current fine-tuning amount of each backlight partition sub-channel and superimpose it onto the reference driving parameters. The system records color differences within historical calibration cycles to calculate the rate of color difference growth. Combined with a safety margin coefficient determined based on panel factory parameters, it adaptively calculates the trigger waiting time for the next calibration to update the calibration trigger cycle.

2. The display screen color management and calibration method according to claim 1, characterized in that, The calculation of the global chromaticity offset, combining the reference white point coordinates and the cumulative illumination duration weights of the backlight zones corresponding to each sampling point, includes: The difference between the measured white point coordinates and the reference white point coordinates is calculated to obtain the chromaticity offset vector of each sampling point. The historical data of the partition duty cycle, which is statistically analyzed in real time by the backlight control module, is obtained, and the cumulative lighting time of the backlight partition corresponding to each sampling point is obtained by integration. Calculate the ratio of the cumulative lighting time to the total lighting time of the entire screen, and determine the weight of each sampling point; The weighted mean of the chromaticity offset vector is calculated using the weights of each sampling point to obtain the global chromaticity offset.

3. The display screen color management and calibration method according to claim 1, characterized in that, The process of selecting nodes to be corrected based on preset color difference uniformity specifications and updating these nodes according to a preset priority order includes: The calculated color difference is compared with the color difference uniformity specification parameter, which serves as the screening threshold. Nodes whose color difference exceeds the filtering threshold are marked as nodes to be corrected and added to the update queue; Determine the priority order from the vicinity of the neutral gray axis at the center of the 3D lookup table space outwards towards the high-saturation vertices; The nodes to be corrected in the update queue are processed in batches according to the priority order, and the update of the nodes to be corrected is finally completed.

4. The display screen color management and calibration method according to claim 1, characterized in that, The process of constructing a full-screen continuous offset field based on the independent offset vector through interpolation, and calculating the local chromaticity compensation vector in conjunction with the spatial boundary of the backlight partition, includes: Using the screen physical coordinates of the multiple sampling points as control points, bilinear interpolation is used to extend the discrete independent offset vectors into a full-screen continuous offset field covering the entire screen; The full-screen continuous offset field is superimposed and matched with the spatial boundaries of each backlight zone; The mean value of the offset field within each backlight zone is calculated to obtain the local chromaticity compensation vector for that zone.

5. The display screen color management and calibration method according to claim 1, characterized in that, The process of solving for the minimum norm solution based on a preset color characteristic matrix to obtain the fine-tuning amount of the driving current for each backlight zone sub-channel and superimposing it onto the reference driving parameters includes: Obtain the color characteristic matrix that describes the linear approximate relationship between the change in driving current and the change in chromaticity coordinates; The generalized inverse of the color characteristic matrix is ​​obtained, and the minimum norm solution is obtained by combining the local chromaticity compensation vector. The minimum norm solution is used as the fine-tuning amount of the driving current for each backlight zone sub-channel; The fine-tuning amount of the driving current is superimposed on the reference driving parameters of the current backlight zone, thereby achieving independent compensation for the local color temperature deviation of each zone.

6. The display screen color management and calibration method according to claim 1, characterized in that, The method of recording color differences within historical correction periods to calculate the rate of color difference growth includes: Maintain a sliding window to record the color difference detected in multiple consecutive corrections in the past; Obtain the time interval between each correction and the last correction; The mean value is calculated based on the ratio of the color difference to the time interval, and the color difference growth rate per unit time is finally obtained.

7. The display screen color management and calibration method according to claim 6, characterized in that, Maintaining a sliding window includes: During the initial operation phase of the equipment, multiple calibration cycles are performed continuously, and the offset sequence of each cycle is recorded. Calculate the autocorrelation function of the offset sequence; Extract the number of hysteresis steps corresponding to the first decay of the autocorrelation coefficient to below a preset threshold; The window length is determined by using the lag step number as the initial value, and the sliding window is finally established.

8. The display screen color management and calibration method according to claim 1, characterized in that, The adaptive calculation of the trigger waiting time for the next correction, based on the safety margin coefficient determined by the panel's factory parameters, includes: Read the panel's initial aging rate and the maximum allowable drift rate at the end of its rated life, as recorded in the panel's factory report; Calculate the ratio of the initial aging rate of the panel to the maximum drift rate, and determine the safety margin factor; The trigger waiting time for the next correction is calculated by dividing the product of the color difference uniformity specification parameter and the safety margin coefficient by the color difference growth rate.

9. The display screen color management and calibration method according to claim 1, characterized in that, The process of driving the backlight partition to output a standard white field excitation signal during the blanking period of the display frame, and simultaneously acquiring the measured white point coordinates of multiple sampling points, includes: The blanking period of the display frame will be used as the measurement time window; Within the measurement time window, each backlight zone is driven to synchronously output the standard white field excitation signal, and the panel is made to appear in a fully white state; By using a miniature color sensor array built into the module frame, sampling points in the central area and four corners of the screen are collected synchronously to obtain the measured coordinates of the white point at the current moment.

10. A display screen color management and calibration method according to claim 1, characterized in that, The calculation of the color difference between the expected chromaticity coordinates and the corrected target chromaticity coordinates corresponding to the output nodes in the 3D lookup table based on the global chromaticity offset includes: Using a uniform color space as a basis, obtain the expected chromaticity coordinates corresponding to each output node in the current three-dimensional lookup table; The expected chromaticity coordinates are corrected using the global chromaticity offset to obtain the corrected target chromaticity coordinates; Based on the expected chromaticity coordinates and the corrected target chromaticity coordinates, combined with the lightness value of the corresponding brightness level of the node, the color difference is finally calculated.

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