A method and system for controlling backlight uniformity of an LCD liquid crystal display

Abstract

The application relates to a backlight uniformity control method and system for an LCD liquid crystal display screen. The method comprises: obtaining first adjustment parameters of a light sensing device inside the display screen and second adjustment parameters of a light emitting device; correcting original brightness readings of the light sensing device based on the first adjustment parameters of the light sensing device and a pre-established performance prediction model of the light sensing device, to obtain corrected brightness readings; compensating original driving instructions of the light emitting device based on the second adjustment parameters of the light emitting device and a pre-established performance prediction model of the light emitting device, to obtain compensated driving instructions; and adjusting driving of the light emitting device based on the corrected brightness readings and the compensated driving instructions, to maintain backlight uniformity of the display screen. Therefore, the backlight uniformity of the LCD liquid crystal display screen after long-term use can be significantly improved, the service life of the display screen is prolonged, and a better visual experience is provided.

Description

Technical Field

[0001] This application relates to the field of display technology, and more specifically, to a method and system for controlling the backlight uniformity of an LCD liquid crystal display screen. Background Technology

[0002] To provide a superior visual experience, especially for displaying High Dynamic Range (HDR) content, LCD (Liquid Crystal Display) backlight systems require extremely high local brightness. This typically means that the LEDs (Light Emitting Diodes) in the backlight module need to operate at significantly higher power in specific areas. However, this continuous high-power operation, over long-term use, not only causes the performance of the internal optical sensors used to monitor brightness to gradually drift, but also accelerates the aging of the LEDs themselves, with this aging exhibiting inconsistencies across different areas.

[0003] Because optical sensors experience performance drift due to prolonged exposure to localized high temperatures, when the backlight system collects brightness data through these sensors, the control logic instructs the LED drive current in that area to perform gain compensation. However, due to inherent biases in the feedback, this compensation is erroneous, causing the LED array in that area to remain in a dynamic "overcompensated" state at a scale imperceptible to the human eye.

[0004] This backlight control system, based on continuous current "overcompensation" using inaccurate feedback, has a cumulative negative impact on the LED array. Specifically, in areas repeatedly "overcompensated" by the system, the light decay rate of the LEDs is significantly accelerated, leading to a faster decline in brightness output. Meanwhile, the LEDs in other normal areas are relatively "healthy," with a slower light decay rate. This differential light decay further exacerbates the deterioration of the brightness uniformity of the entire backlight module after prolonged use, creating a vicious cycle: sensor drift leads to overcompensation, overcompensation accelerates LED aging, and LED aging further exacerbates the actual brightness unevenness. Existing backlight uniformity control methods often struggle to effectively address this complex problem caused by multiple intertwined factors, resulting in visible brightness unevenness in the display after long-term use. Summary of the Invention

[0005] This application discloses a method and system for controlling the backlight uniformity of an LCD display screen, which aims to solve the problem of deterioration in backlight uniformity of LCD display screens after long-term use due to the performance drift of optical sensors and the inconsistency of LED aging.

[0006] In a first aspect, this application discloses a method for controlling the backlight uniformity of an LCD liquid crystal display screen, comprising the following steps: Obtain the first adjustment parameters of the photosensitive device and the second adjustment parameters of the light-emitting device inside the display screen; Based on the first adjustment parameter of the photosensitive device and the pre-established performance prediction model of the photosensitive device, the original brightness reading of the photosensitive device is corrected to obtain the corrected brightness reading. Based on the second adjustment parameter of the light-emitting device and the pre-established performance prediction model of the light-emitting device, the original driving command of the light-emitting device is compensated to obtain the compensated driving command. Based on the corrected brightness readings and compensated drive commands, the drive of the light-emitting devices is adjusted to maintain the backlight uniformity of the display screen.

[0007] Optionally, the step of obtaining the first adjustment parameters of the photosensitive device inside the display screen includes: Obtain the cumulative workload information of the photosensitive device and / or the response deviation ratio of the photosensitive device to each color of light; The steps for correcting the original brightness reading of the photosensitive device based on the first adjustment parameter of the photosensitive device and the pre-established performance prediction model of the photosensitive device to obtain the corrected brightness reading include: The parameters of the photosensitive device performance prediction model are corrected based on the cumulative workload information and / or the proportion of the response deviation of the photosensitive device to each color of light. The original luminance readings were corrected by using a modified photosensitive device performance prediction model to obtain corrected luminance readings.

[0008] Optionally, the step of obtaining the cumulative workload information of the photosensitive device includes: The duration of operation of the photosensitive device in high dynamic range mode and the duration of cumulative high temperature in the area where the photosensitive device is located are obtained. The cumulative workload information of the photosensitive device is obtained based on the duration of operation in high dynamic range mode and the duration of cumulative high temperature in the area where the photosensitive device is located.

[0009] Optionally, the step of correcting the parameters of the photosensitive device performance prediction model based on cumulative workload information includes: The expected decrease in the photosensitive device's response to light intensity is obtained based on the cumulative workload information of the photosensitive device. The parameters of the performance prediction model for photosensitive devices are adjusted based on the expected rate of decrease in responsivity.

[0010] Optionally, the step of obtaining the response deviation ratio of the photosensitive device to each color of light includes: When the display screen is not in operation, control the display screen to sequentially display test patterns of different colors; Collect the brightness readings of the photosensitive device when displaying each test pattern; The brightness readings of the acquired photosensitive device are compared with the initial calibration data of each test pattern to calculate the response deviation ratio of the photosensitive device to each color of light. The steps for correcting the parameters of the photosensitive device performance prediction model based on the proportion of response deviation of the photosensitive device to each color of light include: Based on the calculated spectral response deviation ratio, the performance prediction model of the photosensitive device is corrected, and the prediction parameters for sensitivity deviations of different colors of light are updated. The steps to correct the original luminance reading using the modified photosensitive device performance prediction model to obtain the corrected luminance reading include: During the daily operation of the photosensitive device, the main spectral components of each backlight zone in the current displayed image frame are analyzed in real time. By combining the corrected photosensitive device performance prediction model with the spectral composition of the currently displayed image, a spectral deviation compensation factor is calculated. The original brightness reading of the photosensitive device is multiplied by the spectral deviation compensation factor to obtain the corrected brightness reading.

[0011] Optionally, the step of obtaining the second adjustment parameter of the light-emitting device inside the display screen includes: Obtain the cumulative workload information of the light-emitting devices inside the display screen and / or the actual attenuation ratio of the light-emitting device array for each color of light; The steps for compensating the original driving command of the light-emitting device based on the second adjustment parameter of the light-emitting device and the pre-established performance prediction model of the light-emitting device to obtain the compensated driving command include: The performance prediction model for light-emitting devices is modified based on the cumulative workload information of the light-emitting devices and / or the actual attenuation ratio of each color of light by the light-emitting device array; The original driving command is compensated by the modified light-emitting device performance prediction model to obtain the compensated driving command.

[0012] Optionally, the step of obtaining the cumulative workload information of the light-emitting devices inside the display screen includes: The duration of operation of the light-emitting device inside the display in high dynamic range mode, the duration of cumulative high temperature in the area where the light-emitting device is located, and the duration of high current of the light-emitting device are obtained. The cumulative workload information of the light-emitting device is obtained based on the duration of operation of the light-emitting device in high dynamic range mode, the cumulative high temperature duration of the region, and the high current duration. The steps for correcting the parameters of the light-emitting device performance prediction model based on the cumulative workload information of the light-emitting device include: The expected brightness decay ratio is obtained based on the cumulative workload information of the light-emitting device; The parameters of the performance prediction model for light-emitting devices are adjusted based on the expected brightness decay rate.

[0013] Optionally, the step of obtaining the actual attenuation ratio of each color of light for the light-emitting device array inside the display screen includes: When the display is not in operation, the array of light-emitting devices in each backlight zone is activated, so that it displays the light corresponding to each color in sequence. Collect brightness readings of the photosensitive device when displaying each color; Record the current concentration and temperature of volatile organic compounds inside the backlight module; The collected brightness readings are compared with the initial calibration data of the light-emitting device array to calculate the actual attenuation ratio of the light-emitting device array for each color of light. The steps for correcting the parameters of the light-emitting device performance prediction model based on the actual attenuation ratio of each color of light by the light-emitting device array include: Based on the calculated actual attenuation ratio of each color of light by the light-emitting device array and the recorded concentration and temperature of volatile organic compounds, the parameters of the light-emitting device performance prediction model are corrected, and the independent attenuation prediction functions for red, green and blue light are updated. The steps to obtain the compensated driving command by compensating the original driving command using the modified light-emitting device performance prediction model include: When the backlight control system calculates the target brightness of each light-emitting device array, it queries the updated light-emitting device performance prediction model to obtain the expected attenuation ratio of the light-emitting device array for red, green and blue light. Generate a spectral compensation matrix, which contains compensation factors for each color of light; Multiply the originally calculated driving current by the corresponding spectral compensation factor to obtain the compensated driving current; The instruction for the compensated drive current is sent to the driver chip of the light-emitting device.

[0014] Optionally, the step of adjusting the driving of the light-emitting device based on the corrected brightness reading and the compensated driving command to maintain the backlight uniformity of the display includes: In each backlight zone of the display, multiple micro photosensitive units are deployed, and each micro photosensitive unit corresponds to a local area within the backlight zone; Real-time acquisition of brightness readings for each miniature photosensitive unit; Based on the corrected brightness reading of the backlight zone where the micro photosensitive unit is located and the compensated drive command, the brightness reading of each micro photosensitive unit is calibrated to obtain the calibrated brightness reading of the micro photosensitive unit. Based on the calibrated brightness readings of the miniature photosensitive units, and combined with the brightness requirements of the currently displayed image content in local areas, the brightness error of each local area is calculated. Based on the brightness error of each local region, the light-emitting devices corresponding to the local region are finely adjusted.

[0015] Secondly, this application also discloses an LCD backlight uniformity control system, the system comprising: The acquisition module is used to acquire the first adjustment parameters of the photosensitive device and the second adjustment parameters of the light-emitting device inside the display screen; The photosensitive device calibration module is used to calibrate the original brightness reading of the photosensitive device based on the first adjustment parameters of the photosensitive device and a pre-established performance prediction model of the photosensitive device, so as to obtain the calibrated brightness reading. The light-emitting device compensation module is used to compensate the original driving command of the light-emitting device based on the second adjustment parameter of the light-emitting device and the pre-established performance prediction model of the light-emitting device, so as to obtain the compensated driving command. The drive adjustment module is used to adjust the drive of the light-emitting device based on the corrected brightness reading and the compensated drive command in order to maintain the backlight uniformity of the display screen.

[0016] Beneficial effects The LCD backlight uniformity control method disclosed in this application obtains the adjustment parameters of the photosensitive and light-emitting devices inside the display screen, corrects the original brightness readings of the photosensitive devices based on a pre-established performance prediction model, and compensates the original driving commands of the light-emitting devices. Finally, based on the corrected brightness readings and compensated driving commands, the driving of the light-emitting devices is adjusted to maintain the backlight uniformity of the display screen. This method effectively solves the problems of performance drift caused by long-term exposure of optical sensors to localized high temperatures and the deterioration of backlight uniformity caused by the inconsistency of LED aging in existing technologies. By accurately correcting the readings of the photosensitive devices, the "overcompensation" phenomenon caused by erroneous feedback in the backlight control system is avoided, thereby preventing accelerated aging of the LEDs. Simultaneously, by compensating the driving commands of the light-emitting devices, the light decay problem of the LEDs is directly addressed, ensuring the stability and uniformity of the backlight output. Therefore, this application can significantly improve the backlight uniformity of LCD displays after long-term use, extend the lifespan of the display screen, and provide a better visual experience. Attached Figure Description

[0017] Figure 1This is a flowchart illustrating a method for controlling the backlight uniformity of an LCD display screen according to the first embodiment of this application.

[0018] Figure 2 yes Figure 1 The flowchart of one embodiment of step S2 is shown.

[0019] Figure 3 This is a flowchart illustrating a method for controlling the backlight uniformity of an LCD display screen according to the second embodiment of this application.

[0020] Figure 4 yes Figure 2 The flowchart of one embodiment of step S21 is shown.

[0021] Figure 5 This is a flowchart illustrating a method for controlling the backlight uniformity of an LCD display screen according to the third embodiment of this application.

[0022] Figure 6 yes Figure 2 The flowchart of one embodiment of step S22 is shown.

[0023] Figure 7 yes Figure 1 The flowchart of one embodiment of step S3 is shown.

[0024] Figure 8 This is a flowchart illustrating a method for controlling the backlight uniformity of an LCD display screen according to the fourth embodiment of this application.

[0025] Figure 9 yes Figure 7 The flowchart of one embodiment of step S31 is shown.

[0026] Figure 10 This is a flowchart illustrating a method for controlling the backlight uniformity of an LCD display screen according to the fifth embodiment of this application.

[0027] Figure 11 yes Figure 7 The flowchart of one embodiment of step S32 is shown.

[0028] Figure 12 yes Figure 1 The flowchart of one embodiment of step S4 is shown.

[0029] Figure 13 This is a schematic diagram of the structure of an LCD backlight uniformity control system provided in the sixth embodiment of this application. Detailed Implementation

[0030] The technical solutions of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this application, and not all embodiments. The components of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0031] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this application, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0032] Traditional LCD screens suffer severe backlight uniformity issues after prolonged use, especially when the backlight system requires extremely high local brightness to display high dynamic range (HDR) content. Prolonged localized high heat loads not only cause the performance of the internal optical sensors used to monitor brightness to gradually drift, but also accelerate the aging of the LED chips themselves, with this aging exhibiting inconsistencies across different areas. The deterioration of brightness uniformity across the entire backlight module after prolonged use creates a vicious cycle: sensor drift leads to overcompensation, overcompensation accelerates LED aging, and LED aging further exacerbates actual brightness unevenness. Existing backlight uniformity control methods often struggle to effectively address this complex problem caused by multiple intertwined factors, resulting in visible brightness unevenness in the display after long-term use.

[0033] To address this issue, this application proposes a method for controlling the backlight uniformity of an LCD display screen. Please refer to [link to relevant documentation]. Figure 1 , Figure 1 This is a flowchart illustrating a method for controlling the backlight uniformity of an LCD display screen according to an embodiment of this application. Figure 1 As shown, it includes the following steps: Step S1: Obtain the first adjustment parameters of the photosensitive device and the second adjustment parameters of the light-emitting device inside the display screen.

[0034] Step S2: Based on the first adjustment parameter of the photosensitive device and the pre-established performance prediction model of the photosensitive device, the original brightness reading of the photosensitive device is corrected to obtain the corrected brightness reading.

[0035] Step S3: Based on the second adjustment parameter of the light-emitting device and the pre-established performance prediction model of the light-emitting device, the original driving command of the light-emitting device is compensated to obtain the compensated driving command.

[0036] Step S4: Based on the corrected brightness reading and the compensated drive command, adjust the drive of the light-emitting device to maintain the backlight uniformity of the display screen.

[0037] This application effectively solves the problem of backlight uniformity deterioration caused by device aging and performance drift in traditional methods by introducing a predictive correction and compensation mechanism for the performance of photosensitive and light-emitting devices, thereby significantly improving the long-term stability and image display quality of the display screen.

[0038] In this embodiment, it is first necessary to obtain the first adjustment parameters of the photosensitive device and the second adjustment parameters of the light-emitting device inside the display screen. After obtaining the first adjustment parameters of the photosensitive device, the original brightness reading of the photosensitive device is corrected based on the first adjustment parameters and a pre-established performance prediction model of the photosensitive device to obtain the corrected brightness reading. Specifically, the performance prediction model of the photosensitive device can be a lookup table that stores brightness reading correction factors corresponding to different first adjustment parameters (e.g., cumulative working time). When the current first adjustment parameter is obtained, the system queries the lookup table to obtain the corresponding correction factor, and then multiplies the original brightness reading by the correction factor to obtain the corrected brightness reading. As another implementation, the performance prediction model of the photosensitive device can also be a mathematical function that takes the first adjustment parameter as input and outputs a correction value. For example, if the first adjustment parameter is the cumulative high temperature duration, the model can be a linear decay function that calculates the sensitivity reduction ratio of the photosensitive device based on the cumulative high temperature duration, and then divides the original brightness reading by (1 - sensitivity reduction ratio) to obtain the corrected brightness reading.

[0039] Similarly, after obtaining the second adjustment parameter of the light-emitting device, the original driving command of the light-emitting device is compensated based on the second adjustment parameter and a pre-established performance prediction model of the light-emitting device to obtain a compensated driving command. For example, the performance prediction model of the light-emitting device can be a polynomial function that takes the second adjustment parameter (e.g., cumulative workload information) as input and outputs a brightness attenuation ratio. The system calculates the required increase in driving current based on this attenuation ratio, and then adds this increment to the original driving command to obtain the compensated driving command. As another implementation, the performance prediction model of the light-emitting device can also be a neural network model. This model, by learning a large amount of light-emitting device aging data, can predict the brightness output characteristics of the light-emitting device under different spectra based on the second adjustment parameter (e.g., the actual attenuation ratio of the light-emitting device array for each color of light). When the system needs to drive the light-emitting device, the original driving command and the second adjustment parameter are input into the neural network model, and the model outputs a compensated driving command to ensure that the light-emitting device can output the target brightness.

[0040] Finally, based on the corrected brightness readings and compensated drive commands, the driving of the light-emitting devices is adjusted to maintain the backlight uniformity of the display screen. For example, the backlight control system can receive corrected brightness readings from multiple photosensitive devices and compare them with a preset target brightness to calculate the brightness error of each backlight zone. Simultaneously, the system calculates the actual drive current of each light-emitting device array based on the image content and the compensated drive commands. Then, the system can use a PID (Proportional-Integral-Derivative) controller to adjust the drive current of each light-emitting device array in real time according to the brightness error and the compensated drive commands to eliminate the brightness error and maintain the backlight uniformity of the display screen. As a preferred embodiment, multiple miniature photosensitive units can be deployed within each backlight zone of the display screen, with each miniature photosensitive unit corresponding to a local area within the backlight zone. The brightness readings of each miniature photosensitive unit are acquired in real time, and the brightness readings of each miniature photosensitive unit are calibrated based on the corrected brightness readings of the backlight zone where the miniature photosensitive unit is located and the compensated drive commands, resulting in calibrated brightness readings for each miniature photosensitive unit. Based on the calibrated brightness readings of the miniature photosensitive units and the brightness requirements of the currently displayed image content in local areas, the brightness error for each local area is calculated. Finally, based on the brightness error of each local area, the corresponding light-emitting devices in that local area are fine-tuned.

[0041] The LCD backlight uniformity control method proposed in this application effectively addresses the problem of backlight uniformity deterioration that occurs after long-term use of the display screen by predictively correcting and compensating the performance of the photosensitive device and the light-emitting device.

[0042] Traditional backlight uniformity control methods often rely on real-time brightness feedback, but ignore the aging and drift of the performance of photosensitive and light-emitting devices over time. When the readings of the photosensitive device deviate, the system will incorrectly adjust the drive of the light-emitting device, leading to a vicious cycle and accelerating the deterioration of backlight uniformity.

[0043] This application performs pre-processing, aging-based correction and compensation on the brightness readings of the photosensitive device and the driving commands of the light-emitting device. This predictive mechanism enables the system to "anticipate" and "correct" performance deviations of the devices, rather than passively responding to inaccurate feedback.

[0044] In some embodiments described above, this application proposes correcting the original brightness reading by obtaining a first adjustment parameter of the photosensitive device and based on a pre-established performance prediction model of the photosensitive device. However, in actual implementation, the performance of the photosensitive device can drift or degrade with changes in time, usage environment, and workload. If only a pre-established fixed model and general adjustment parameters are relied upon, the real-time state of the photosensitive device may not be accurately reflected, resulting in deviations in the corrected brightness reading and thus affecting the accuracy of backlight uniformity control.

[0045] In this regard, the "obtaining the first adjustment parameters of the photosensitive device inside the display screen" in step S1 can specifically obtain the cumulative workload information of the photosensitive device and / or the response deviation ratio of the photosensitive device to each color of light.

[0046] Specifically, the cumulative workload information may include the total operating time of the photosensitive device, the duration of operation under high brightness or high temperature environments, etc. The response deviation ratio of the photosensitive device to each color of light refers to the degree of difference between the output response of the photosensitive device and the ideal or initial calibration value when sensing different colors of light (e.g., red, green, and blue). Its purpose is to capture changes in the spectral response characteristics of the photosensitive device, because the spectral sensitivity of the photosensitive device may undergo non-uniform drift with aging.

[0047] The solution proposed in this application, by incorporating the cumulative workload information of the photosensitive device and / or the proportion of its response deviation to each color of light, enables a more comprehensive assessment of the current performance status of the photosensitive device. Specifically, the cumulative workload information reflects the overall aging degree of the photosensitive device, while the proportion of its response deviation to each color of light reveals the specific changes in its spectral response characteristics. It is precisely because these dynamically changing parameters are taken into account that the pre-established photosensitive device performance prediction model can be corrected in real time or periodically.

[0048] Based on the cumulative workload information of the photosensitive device and / or the proportion of response deviation of the photosensitive device to each color of light, please refer to Figure 2The technical solution in step S2 above, which involves "correcting the original brightness reading of the photosensitive device based on the first adjustment parameter of the photosensitive device and the pre-established performance prediction model of the photosensitive device, to obtain the corrected brightness reading," can specifically include the following steps: Step S21: Correct the parameters of the photosensitive device performance prediction model based on the cumulative workload information and / or the response deviation ratio of the photosensitive device to each color of light.

[0049] Step S22: Correct the original brightness reading using the modified photosensitive device performance prediction model to obtain the corrected brightness reading.

[0050] In practical applications, the performance prediction model for photosensitive devices is typically established at the time of manufacture, but its parameters need to be dynamically adjusted based on the actual aging of the photosensitive device. Parameter correction of the performance prediction model refers to updating or adjusting relevant parameters in the model based on acquired cumulative workload information and / or the proportion of response deviation of the photosensitive device to each color of light, so as to more accurately reflect the current performance status of the photosensitive device. For example, the gain coefficient, offset, or spectral response curve parameters in the model can be adjusted. Therefore, the corrected performance prediction model is a model that is updated in real time or periodically, and it can more accurately predict the brightness reading of the photosensitive device under given lighting conditions, thus providing a more reliable basis for subsequent brightness correction.

[0051] By correcting the model parameters, the model can more accurately simulate the actual response of the photosensitive device under the current state, thus making the correction of the original brightness reading more precise. This dynamic correction mechanism effectively solves the problem of inaccurate correction caused by the drift of photosensitive device performance over time, ensuring the accuracy of subsequent backlight drive adjustments.

[0052] The above technical solution overcomes the impact of photosensitive device performance drift on the accuracy of brightness reading correction in traditional methods. By dynamically acquiring and utilizing the cumulative workload information of the photosensitive device and / or its response deviation ratio to different colors of light, the parameters of the photosensitive device performance prediction model are corrected, allowing the corrected brightness reading to more accurately reflect the actual brightness distribution of the display screen. This significantly improves the accuracy and reliability of photosensitive device brightness readings, provides more precise input data for LCD backlight uniformity control, effectively enhances the backlight uniformity of the display screen, extends its lifespan, and improves the user's visual experience.

[0053] Specifically, the above-mentioned technical solution for obtaining the cumulative workload information of the photosensitive device can be further refined. Please refer to [link / reference]. Figure 3 The technical solution for obtaining the cumulative workload information of a photosensitive device may include the following steps: Step S11: Obtain the duration of operation of the photosensitive device in high dynamic range mode and the duration of cumulative high temperature in the area where the photosensitive device is located.

[0054] Step S12: Obtain the cumulative workload information of the photosensitive device based on the duration of operation in high dynamic range mode and the duration of cumulative high temperature in the area where the photosensitive device is located.

[0055] The duration of operation of the image sensor in high dynamic range (HDR) mode refers to the total time the image sensor experiences while processing HDR content. In HDR mode, the image sensor typically needs to capture image information at a higher sampling rate, a wider dynamic range, or more frequent readings, which puts greater stress and wear on its internal components. Therefore, recording this duration helps quantify the cumulative wear and tear on the image sensor under harsh operating conditions.

[0056] Furthermore, the cumulative high-temperature duration of the area where the photosensitive device is located refers to the total time the photosensitive device operates in an environment above its normal operating temperature range. High temperature is one of the main factors leading to performance degradation and shortened lifespan of electronic components. When photosensitive devices are exposed to high-temperature environments for extended periods, key performance indicators such as photoelectric conversion efficiency, dark current characteristics, and response speed may drift. Therefore, by monitoring and accumulating the high-temperature duration, the performance degradation of photosensitive devices caused by thermal stress can be assessed more accurately.

[0057] This application's solution, by obtaining the duration of the photosensitive device's operation in high dynamic range mode and the duration of the accumulated high temperature in the region where the photosensitive device is located, can more comprehensively and accurately assess the actual cumulative workload of the photosensitive device. Operation in high dynamic range mode increases the internal circuitry burden and data processing volume of the photosensitive device, while prolonged high-temperature environments accelerate material aging and performance drift. These factors are all important causes of photosensitive device performance degradation. By quantifying these key parameters, more refined inputs can be provided to the photosensitive device performance prediction model, enabling the model to more accurately predict the current performance state of the photosensitive device, such as the percentage decrease in its luminance responsivity or spectral response deviation.

[0058] The above technical solution enables more precise acquisition of the cumulative workload information of the photosensitive device, allowing the photosensitive device performance prediction model to more accurately reflect the actual aging and performance degradation of the photosensitive device. This helps improve the correction accuracy of the original brightness readings of the photosensitive device, ensuring that the brightness readings accurately reflect the actual backlight brightness throughout the entire lifespan of the display. This provides a more reliable input for subsequent adjustments to the light-emitting device drive, ultimately effectively maintaining the backlight uniformity of the LCD screen and improving display quality and user experience.

[0059] In some embodiments described above in this application, a scheme is proposed to correct the parameters of a photosensitive device performance prediction model based on cumulative workload information. However, in its implementation, correction based solely on cumulative workload information may not accurately reflect the actual attenuation of the photosensitive device's brightness response, thus affecting the accuracy of the prediction model. If this problem is not addressed, the brightness reading correction of the photosensitive device may be inaccurate, thereby affecting the overall effect of backlight uniformity control of the display screen.

[0060] In response, this application further proposes specific steps for the technical solution of "correcting the parameters of the photosensitive device performance prediction model based on the cumulative workload information" in step S21 above. Please refer to [link to relevant documentation]. Figure 4 Specifically, it may include: Step S211: Obtain the expected decrease rate of the photosensitive device's response to light intensity based on the cumulative workload information of the photosensitive device.

[0061] Step S212: Adjust the parameters of the photosensitive device performance prediction model based on the expected decrease in responsivity.

[0062] Specifically, the aforementioned "obtaining the expected decrease in the photosensitive device's response to light intensity based on the cumulative workload information of the photosensitive device" refers to the system using the cumulative workload information of the photosensitive device, such as its total operating time, exposure time under high-intensity light, and duration under high-temperature conditions, to calculate, through a preset attenuation model or lookup table, the percentage or proportion by which the photosensitive device's response to light intensity is expected to decrease under the current cumulative workload. This attenuation model can be established based on a large amount of experimental data and aging test results, and is used to quantify the impact of different workloads on the performance of the photosensitive device.

[0063] The phrase "adjusting parameters of the photosensitive device performance prediction model based on the expected rate of response reduction" can be understood as using the obtained expected rate of response reduction as input to adjust the parameters within the photosensitive device performance prediction model. For example, the model's gain coefficient, offset, or nonlinear response curve can be adjusted to more accurately predict the actual brightness reading of the photosensitive device under its current aging state. The aim is to enable the photosensitive device performance prediction model to dynamically adapt to the aging characteristics of the photosensitive device, thereby improving its prediction accuracy.

[0064] This application addresses the problem of accurately correcting photosensitive device performance prediction models based solely on vague cumulative workload information by converting the cumulative workload information of the photosensitive device into a specific expected responsivity degradation ratio. Under long-term operation and specific environmental conditions (such as high temperature and high-intensity light), the photosensitive materials inside the photosensitive device undergo physical or chemical changes, leading to a gradual decrease in its light response capability. This degradation is not a simple linear relationship but is complexly related to various workload factors. By obtaining the expected responsivity degradation ratio, this application can quantify this physical attenuation and directly map it to the adjustment of model parameters. It is precisely this quantification and mapping that enables the photosensitive device performance prediction model to more accurately reflect the actual performance state of the photosensitive device, thus providing a more reliable basis for subsequent brightness reading correction.

[0065] In some preferred embodiments, a specific example is illustrated below. Suppose a photosensitive device has accumulated 2000 hours of operation in high dynamic range mode over the past year, and the cumulative high-temperature duration in its operating region has reached 500 hours. The system first queries a pre-established photosensitive device aging database or degradation curve. This database may contain typical responsivity degradation data for photosensitive devices under different combinations of operating time, temperature, and operating mode. Based on the query results, the system calculates that the expected reduction in the current photosensitive device's luminance is 3%. Subsequently, this 3% expected luminance reduction percentage is input into the photosensitive device performance prediction model. For example, if the model is a linear model whose output is `luminance reading = gain * actual luminance + offset`, then this 3% reduction percentage can be used to adjust the gain parameter, changing it from the initial 1.0 to 0.97, or to adjust the offset to compensate for the overall decrease in sensitivity. In this way, even if the actual response capability of the photosensitive device decreases due to aging, the corrected model can still accurately correct the original luminance reading to a value close to the true luminance.

[0066] In some embodiments described above, the performance prediction model of the photosensitive device is used to correct the original brightness reading, taking into account the response deviation ratio of the photosensitive device to each color of light. However, if this response deviation ratio is not accurately obtained, and the spectral characteristics of the current displayed image are not fully considered during the correction process, the corrected brightness reading may be biased, thus affecting the precise control of backlight uniformity. To address this, this application further proposes a more refined method to obtain the response deviation ratio of the photosensitive device to each color of light, and based on this, to modify the parameters of the photosensitive device performance prediction model. Finally, by combining the spectral composition of the current displayed image, the original brightness reading is corrected to achieve more accurate brightness perception.

[0067] Specifically, please refer to Figure 5 The aforementioned technical solution for "obtaining the response deviation ratio of the photosensitive device to each color of light" includes the following steps: Step S13: During non-working hours of the display screen, control the display screen to sequentially display test patterns of different colors.

[0068] Step S14: Collect the brightness reading of the photosensitive device when displaying each test pattern.

[0069] Step S15: Compare the collected brightness readings of the photosensitive device with the initial calibration data of each test pattern, and calculate the response deviation ratio of the photosensitive device to each color of light.

[0070] The non-working time of the display screen refers to the period when the display screen is not in normal image display or user interaction mode, such as when the device is in standby, hibernation, or undergoing system maintenance. During this period, the display screen can be controlled to sequentially display preset test patterns of different colors with known spectral characteristics, such as pure red, pure green, pure blue, and pure white. The photosensitive device is configured to collect the corresponding brightness reading when each test pattern is displayed. These brightness readings reflect the actual response of the photosensitive device under specific color light. Initial calibration data refers to the ideal or standard brightness response value of the photosensitive device recorded for each test pattern during the display screen's factory manufacturing or initial calibration. By comparing the actually collected brightness readings with these initial calibration data, the response deviation of the photosensitive device to different colors of light can be quantified, thereby calculating the proportion of response deviation of the photosensitive device to each color of light.

[0071] The technical solution of "correcting the parameters of the photosensitive device performance prediction model according to the response deviation ratio of the photosensitive device to each color of light" in step S21 above is as follows: correct the photosensitive device performance prediction model according to the calculated spectral response deviation ratio, and update the prediction parameters for sensitivity deviation of different colors of light.

[0072] Specifically, the spectral response deviation ratio refers to the degree to which the sensitivity of a photosensitive device to a specific color of light deviates from its initial calibration state. Based on these calculated deviation ratios, relevant parameters in the photosensitive device performance prediction model are revised to more accurately reflect the aging or performance drift of the photosensitive device under different colors of light. These updated prediction parameters enable the model to provide more accurate sensitivity deviation predictions for different colors of light, such as red, green, and blue.

[0073] Please see Figure 6 The technical solution in step S22 above, which involves "correcting the original brightness reading using the modified photosensitive device performance prediction model to obtain the corrected brightness reading," includes the following steps: Step S221: During the normal operation of the photosensitive device, analyze the main spectral components of each backlight zone in the current display image frame in real time.

[0074] Step S222: Calculate the spectral deviation compensation factor by combining the corrected photosensitive device performance prediction model and the spectral composition of the currently displayed image.

[0075] Step S223: Multiply the original brightness reading of the photosensitive device by the spectral deviation compensation factor to obtain the corrected brightness reading.

[0076] In practical applications, during the daily operation of the photosensitive device, the display system is configured to analyze the main spectral components of the currently displayed image frame within each backlight zone in real time. This can be done, for example, by statistical analysis of the RGB values ​​of image pixels or by using a pre-defined image content classification algorithm. Subsequently, by combining a corrected photosensitive device performance prediction model with the currently analyzed image spectral components, a spectral deviation compensation factor can be calculated. This compensation factor is used to quantify the difference between the actual and ideal response of the photosensitive device under the current spectral environment. Finally, multiplying the original luminance reading of the photosensitive device by this spectral deviation compensation factor yields the luminance reading corrected for spectral characteristics, thereby improving the accuracy of luminance measurement.

[0077] Through the above technical solution, this application can significantly improve the accuracy and stability of backlight uniformity control for LCD screens. Specifically, by accurately calibrating the spectral response deviation of the photosensitive device during non-working hours and dynamically compensating in real time with the spectral components of the displayed image, the influence of spectral sensitivity drift caused by aging or environmental factors on the accuracy of brightness measurement can be effectively eliminated. Therefore, the brightness readings provided by the photosensitive device will more accurately reflect the actual luminous state of the backlight module, avoiding misjudgments caused by spectral response mismatch that may occur in traditional methods. This refined calibration mechanism enables the backlight control system to make decisions based on more accurate brightness data, thereby achieving more precise backlight zone brightness adjustment, ultimately maintaining excellent backlight uniformity and color performance of the display under various display content, and improving the user's visual experience.

[0078] In some preferred embodiments, a specific example is given below. Assume that an LCD screen, at the time of manufacture, has its photosensitive sensor calibrated to respond to pure red, pure green, and pure blue light with values ​​of R0, G0, and B0, respectively. After a period of use, during the screen's non-operating hours, the system is activated to execute a calibration procedure. First, the screen sequentially displays a pure red test pattern, with the photosensitive sensor acquiring a brightness reading of R1. Next, a pure green test pattern is displayed, with a brightness reading of G1. Finally, a pure blue test pattern is displayed, with a brightness reading of B1. By comparison, the response deviation ratio for red light is calculated as (R1-R0) / R0, for green light as (G1-G0) / G0, and for blue light as (B1-B0) / B0. These deviation ratios are used to correct the spectral sensitivity parameters in the photosensitive sensor performance prediction model.

[0079] During normal operation, when the display shows a frame of an image, the backlight control system analyzes the main spectral components of that frame within a specific backlight zone in real time. For example, if the zone primarily displays a blue sky, its main spectral component is blue. At this point, the corrected photosensitive sensor performance prediction model predicts the actual response deviation of the photosensitive sensor to blue light based on the blue spectral component of the current image and calculates a spectral deviation compensation factor. Assuming the original luminance reading of the photosensitive sensor is L_raw and the compensation factor is C_blue, then the corrected luminance reading L_corrected will be calculated as L_raw * C_blue. In this way, even if the sensitivity of the photosensitive sensor to blue light changes, its output luminance reading can be accurately corrected, thereby ensuring precise adjustment of the backlight drive and maintaining the backlight uniformity of the display.

[0080] In some embodiments described above, this application proposes to compensate for the original driving commands of the light-emitting device (LED) based on a second adjustment parameter and a pre-established LED performance prediction model, in order to maintain the backlight uniformity of the display screen. However, in practical applications, the performance of the LED gradually degrades with factors such as usage time, workload, and environmental conditions, and this degrade may not occur uniformly across all color spectra. If the LED performance prediction model fails to reflect the actual degraded state of the LED in a timely and accurate manner, the compensated driving commands may not accurately match the true needs of the LED, thereby affecting backlight uniformity and color accuracy.

[0081] In this regard, this application further proposes a technical solution for "obtaining the second adjustment parameter of the light-emitting device inside the display screen" in step S1 above, which specifically involves obtaining the cumulative workload information of the light-emitting device inside the display screen and / or the actual attenuation ratio of the light-emitting device array for each color of light.

[0082] Please see Figure 7 The technical solution in step S3 above, which involves "compensating the original driving command of the light-emitting device based on the second adjustment parameter of the light-emitting device and the pre-established performance prediction model of the light-emitting device to obtain the compensated driving command," includes the following steps: Step S31: Adjust the parameters of the light-emitting device performance prediction model based on the cumulative workload information of the light-emitting device and / or the actual attenuation ratio of each color of light by the light-emitting device array.

[0083] Step S32: Compensate the original driving command using the modified light-emitting device performance prediction model to obtain the compensated driving command.

[0084] Specifically, the cumulative workload information of a light-emitting device (LED) can be understood as the stress and usage intensity it endures throughout its entire lifespan, such as its total operating time, duration in high-brightness or high-current modes, and the cumulative duration of high-temperature conditions in its environment. This information is a key indicator for predicting the overall brightness decay and lifespan of the LED. The actual decay ratio of each color of light emitted by the LED array refers to the degree of decrease in brightness output relative to the initial calibration or ideal value when emitting different colors of light. Since different colors of LEDs or luminescent materials may have different aging characteristics, independently evaluating the decay of each color of light can more accurately reflect the spectral performance changes of the LED array.

[0085] Furthermore, the performance prediction model for the light-emitting devices (LEDs) is modified based on the cumulative workload information of the LEDs and / or the actual attenuation ratio of each color of light by the LED array. This aims to enable the prediction model to dynamically adapt to the actual aging condition of the LEDs. For example, when the cumulative workload information indicates that the LEDs have reached a certain lifespan, the parameters related to brightness attenuation in the model will be adjusted to reflect the expected overall brightness decrease. When a change in the attenuation ratio of a specific color of light by the LED array is detected, the attenuation prediction function for the corresponding color channel in the model will be updated to more accurately predict the actual output of that color of light. Thus, by compensating the original drive commands with the modified LED performance prediction model, it can be ensured that the compensation commands are calculated based on the latest and most accurate performance state of the LEDs, thereby achieving more refined and effective drive control.

[0086] The solution proposed in this application introduces the cumulative workload information of the light-emitting device and / or the actual attenuation ratio of the light-emitting device array for each color of light as a second adjustment parameter, and dynamically corrects the light-emitting device performance prediction model accordingly, thereby solving the problem that the light-emitting device performance prediction model in traditional methods may not accurately reflect the actual aging state of the light-emitting device.

[0087] Through the above technical solution, this application can significantly improve the accuracy and adaptability of backlight uniformity control for LCD displays. Specifically, by considering the cumulative workload information of the light-emitting devices, the overall aging trend of the light-emitting devices can be predicted more accurately, thereby achieving more effective brightness compensation. Furthermore, by acquiring and utilizing the actual attenuation ratio of each color of light by the light-emitting device array, this application can specifically compensate for the attenuation differences of different colors of light, effectively avoiding color distortion caused by spectral drift and ensuring the accuracy of color reproduction of the display. This method of dynamically correcting the light-emitting device performance prediction model enables the system to continuously adapt to the aging process of the light-emitting devices, thereby maintaining excellent backlight uniformity and color performance throughout the entire lifespan of the display, extending the effective lifespan of the display, and improving the user experience.

[0088] In some preferred embodiments, a specific example is given below. Assume that when an LCD screen leaves the factory, its light-emitting device performance prediction model has been established based on initial calibration data. As the screen is put into use, the system continuously records the cumulative workload information of the light-emitting devices, such as their total on-time, the duration of operation in high-brightness mode, and the cumulative high-temperature readings of the internal temperature sensor. For example, during non-operating times, the system can periodically activate the light-emitting device array, causing it to sequentially display test light of different colors such as red, green, and blue, and collect corresponding brightness readings through photosensitive devices. By comparing these readings with the initial calibration data, the actual attenuation ratio of the light-emitting device array for each color of light can be calculated.

[0089] Subsequently, this accumulated workload information and actual attenuation ratio are input into the light-emitting device performance prediction model to correct the model's parameters. For example, if the attenuation ratio of the red light-emitting device is detected to be higher than that of the green and blue light-emitting devices, the attenuation prediction function for red light in the model will be adjusted to reflect this change. When the backlight control system needs to calculate drive instructions for a certain backlight zone, it queries this corrected light-emitting device performance prediction model to obtain the expected attenuation ratio of the light-emitting device array for red, green, and blue light. Based on these expected attenuation ratios, the system generates a spectral compensation matrix containing compensation factors for each color of light. Finally, the originally calculated drive current is multiplied by the corresponding spectral compensation factor to obtain the compensated drive current, which is then sent to the light-emitting device driver chip. In this way, even if the performance of the light-emitting device degrades due to aging, its output brightness and color can be maintained at the target level through precise compensation, thereby ensuring the backlight uniformity and color accuracy of the display.

[0090] In some embodiments described above, this application proposes a scheme to obtain the cumulative workload information of the light-emitting devices inside the display screen and to correct the parameters of the light-emitting device performance prediction model based on this information. However, in its implementation, simply obtaining generalized cumulative workload information may not be sufficient to capture the specific aging mechanisms of the light-emitting devices under different harsh operating conditions, such as high dynamic range (HDR) mode, high temperature environment, and high current drive. These factors have significant and differentiated effects on the performance degradation of the light-emitting devices. If the above problems are not addressed, the prediction of the actual performance degradation of the light-emitting devices may be inaccurate, thereby affecting the accuracy of backlight uniformity control and display effect. To address this, this application further proposes a specific method for obtaining the cumulative workload information of the light-emitting devices and, based on this, more accurately corrects the light-emitting device performance prediction model.

[0091] For details, please refer to Figure 8 The technical solution for "obtaining the cumulative workload information of the light-emitting devices inside the display screen" mentioned above includes the following steps: Step S81: Obtain the duration of operation of the light-emitting device inside the display screen in high dynamic range mode, the duration of the cumulative high temperature in the area where the light-emitting device is located, and the duration of high current of the light-emitting device.

[0092] Step S82: Obtain the cumulative workload information of the light-emitting device based on the duration of operation of the light-emitting device in high dynamic range mode, the duration of cumulative high temperature in the region, and the duration of high current.

[0093] Please continue reading. Figure 9 The technical solution in step S31 above, which involves "correcting the parameters of the performance prediction model of the light-emitting device based on the cumulative workload information of the light-emitting device," includes the following steps: Step S311: Obtain the expected brightness decay ratio based on the cumulative workload information of the light-emitting device.

[0094] Step S312: Correct the parameters of the light-emitting device performance prediction model according to the expected brightness decay ratio.

[0095] The duration of operation of a light-emitting device (LED) in high dynamic range (HDR) mode refers to the total time the LED is driven at higher brightness or higher current when displaying HDR content. HDR mode typically places higher demands on the performance of LEDs, and prolonged operation accelerates their aging. The cumulative high-temperature duration of the LED's operating area refers to the total time the LED operates beyond its normal operating temperature range. High temperature is a key factor contributing to LED performance degradation. The high-current duration of the LED refers to the total time the LED operates above its rated current or normal operating current; high current also accelerates device aging and brightness decay.

[0096] In practical applications, obtaining the cumulative workload information of a light-emitting device (LED) can be understood as comprehensively considering the impact of the three durations mentioned above on the performance degradation of the LED. For example, a cumulative workload index that can quantify the aging degree of the LED can be obtained by weighted summation of these three durations or by calculation using a preset degradation model. Furthermore, obtaining the expected brightness degradation ratio based on the cumulative workload information of the LED refers to predicting the degree of brightness output degradation of the LED under the current cumulative workload relative to its initial state, based on the cumulative workload information, through table lookup, curve fitting, or a preset algorithm. This expected brightness degradation ratio is a key parameter used to quantify the performance degradation of the LED. Its purpose is to enable the LED performance prediction model to more accurately reflect the actual aging state of the LED. For example, the predicted brightness output of the model can be made consistent with the actual brightness degradation trend by adjusting the degradation coefficient and lifetime curve parameters in the model.

[0097] This application's solution refines the acquisition method of cumulative workload information for light-emitting devices (LEDs), taking the duration of operation in high dynamic range mode, the duration of cumulative high temperature, and the duration of high current as key considerations. These factors are directly related to the accelerated aging mechanism of LEDs, and can more comprehensively and accurately reflect the actual performance degradation of LEDs. By integrating these specific parameters, the cumulative workload of LEDs can be quantified more precisely, thereby deriving a more accurate expected brightness degradation ratio. It is precisely because of the more refined prediction of LED performance degradation that the LED performance prediction model can receive more targeted parameter corrections, thus improving the model's accuracy in predicting the future performance of LEDs.

[0098] In some embodiments described above in this application, a scheme is proposed to correct the performance prediction model of the light-emitting device and compensate for the original driving command based on the cumulative workload information of the light-emitting device and / or the actual attenuation ratio of the light-emitting device array for each color of light. However, in practical applications, the performance degradation of the light-emitting device is not only related to the cumulative workload, but may also be affected by environmental factors (such as temperature and volatile organic compound concentration). These factors may cause the spectral characteristics of the light-emitting device to drift, thereby affecting the color accuracy and backlight uniformity of the display screen. If only a simple attenuation ratio is relied upon for correction, it may not be able to adequately cope with these complex and dynamically changing attenuation mechanisms, resulting in poor compensation effect, especially under long-term use or large environmental changes.

[0099] In response, this application further proposes a more refined method for obtaining the actual attenuation ratio of each color of light for the light-emitting device array and for correcting the performance prediction model of the light-emitting device and compensating the original driving command based on this. This method achieves accurate modeling and compensation of the performance degradation of the light-emitting device by performing spectral measurements in a non-working state and combining them with environmental parameters.

[0100] Please see Figure 10 The aforementioned technical solution for "obtaining the actual attenuation ratio of each color of light by the light-emitting device array inside the display screen" includes the following steps: Step S101: When the display screen is not in operation, activate the array of light-emitting devices in each backlight zone so that it displays the light corresponding to each color in sequence.

[0101] Step S102: Collect the brightness reading of the photosensitive device when displaying each color.

[0102] Step S103: Record the concentration and temperature of volatile organic compounds inside the current backlight module.

[0103] Step S104: Compare the collected brightness readings with the initial calibration data of the light-emitting device array, and calculate the actual attenuation ratio of the light-emitting device array for each color of light.

[0104] The technical solution of "correcting the parameters of the light-emitting device performance prediction model according to the actual attenuation ratio of each color of light by the light-emitting device array" in step S31 above is as follows: based on the calculated actual attenuation ratio of each color of light by the light-emitting device array and the recorded concentration and temperature of volatile organic compounds, the parameters of the light-emitting device performance prediction model are corrected, and the independent attenuation prediction functions for red, green and blue light are updated.

[0105] Please see Figure 11The technical solution in step S32 above, which involves "compensating the original driving command by using the corrected light-emitting device performance prediction model to obtain the compensated driving command," specifically includes the following steps: Step S321: When the backlight control system calculates the target brightness of each light-emitting device array, it queries the updated light-emitting device performance prediction model to obtain the expected attenuation ratio of the light-emitting device array for red, green and blue light.

[0106] Step S322: Generate a spectral compensation matrix containing compensation factors for each color of light.

[0107] Step S323: Multiply the originally calculated driving current by the corresponding spectral compensation factor to obtain the compensated driving current.

[0108] Step S324: Send the instruction for the compensated drive current to the light-emitting device driver chip.

[0109] Specifically, the non-working state of the display screen refers to a state where the display screen is not in normal image display or user interaction, such as during standby, screen-off, or system maintenance. During this period, dedicated testing operations can be performed on the backlight module to avoid interfering with the user experience. Activating the light-emitting device array within each backlight zone allows it to sequentially display different colors of light, such as red, green, and blue. The purpose is to independently evaluate the performance of the light-emitting devices under different spectra, providing basic data for subsequent attenuation ratio calculations. The photosensitive device can be understood as a light sensor integrated inside the display screen or backlight module, used to accurately measure the brightness of the light emitted by the light-emitting device array. By collecting the brightness readings of the photosensitive device when the light-emitting device array displays each color of light, the actual output intensity of the light-emitting device for different colors of light in the current state can be obtained.

[0110] In practical applications, volatile organic compound (VOC) concentration and temperature are important environmental factors affecting the long-term performance and spectral stability of light-emitting devices (LEDs). For example, some VOCs may react with the encapsulation materials or emissive layers of LEDs, accelerating their aging; temperature changes directly affect luminous efficiency and spectral drift. Therefore, recording these environmental parameters simultaneously during performance evaluation aims to provide more comprehensive environmental context information for revising LED performance prediction models, thereby improving prediction accuracy. Specifically, initial calibration data refers to the ideal brightness output data of the LED array measured under standard environmental conditions when it leaves the factory or is first installed. By comparing the currently acquired brightness readings with these initial calibration data, the actual attenuation of the LED array under different colors of light can be quantified, thus obtaining the actual attenuation ratio of the LED array for each color of light.

[0111] The light-emitting device (LED) performance prediction model is a mathematical or algorithmic model used to predict the performance degradation of LEDs under different operating conditions and time. Based on the calculated actual degradation ratio and combined with recorded VOC concentration and temperature, the parameters of the model can be finely corrected. Furthermore, this correction process can update the independent degradation prediction functions for red, green, and blue light contained in the model. This means that the model can predict the degradation of the LED in the red, green, and blue channels separately, thus more accurately reflecting its spectral drift characteristics.

[0112] Specifically, the backlight control system determines the target brightness required for each light-emitting device (LED) array based on the displayed image content and user settings. After determining the target brightness, the system queries a revised and updated LED performance prediction model to obtain the expected attenuation ratios for red, green, and blue light in the current operating state. These expected attenuation ratios reflect the aging degree of the LEDs in different color channels. Based on this, the system generates a spectral compensation matrix according to the obtained expected attenuation ratios. This matrix is ​​a mathematical structure containing independent compensation factors for red, green, and blue light. Each compensation factor is used to offset the expected attenuation of the corresponding color light, ensuring that the final output spectral composition is consistent with the expected value. Further, the originally calculated drive current is derived based on the LED performance under ideal conditions. By multiplying these original drive currents by the corresponding spectral compensation factors in the spectral compensation matrix, a precisely adjusted and compensated drive current can be obtained. The purpose of this operation is to accurately compensate for the attenuation in different color channels when driving the LEDs, thereby maintaining color accuracy. Finally, these compensated drive current commands are sent to the LED driver chip. The driver chip precisely controls the current output of the light-emitting device according to the received instructions, ensuring that the backlight module can emit light according to the corrected instructions, thereby effectively compensating for the performance degradation of the light-emitting device and maintaining the backlight uniformity and color accuracy of the display screen.

[0113] In some embodiments described above, this application proposes adjusting the driving of the light-emitting devices based on corrected brightness readings and compensated driving commands to maintain backlight uniformity of the display screen. However, in practical applications, even with overall correction and compensation, the backlight uniformity within the display screen may still be affected by local area differences. For example, minor manufacturing tolerances, local hot spots, or uneven aging of the light-emitting or photosensitive devices can lead to slight brightness inconsistencies within larger backlight zones. Failure to address these local non-uniformities may affect the final display quality and user experience. Therefore, this application further proposes a more refined method for adjusting the driving of the light-emitting devices. By deploying micro-photosensitive units within each backlight zone, precise perception and differentiated fine-tuning of local area brightness can be achieved, thereby significantly improving backlight uniformity.

[0114] Specifically, please refer to Figure 12 The technical solution in step S4 above, which involves "adjusting the driving of the light-emitting device based on the corrected brightness reading and the compensated driving command to maintain the backlight uniformity of the display screen," includes the following steps: Step S41: In each backlight zone of the display screen, multiple micro photosensitive units are deployed, each micro photosensitive unit corresponding to a local area within the backlight zone.

[0115] Step S42: Collect the brightness reading of each micro photosensitive unit in real time.

[0116] Step S43: Based on the corrected brightness reading of the backlight zone where the micro photosensitive unit is located and the compensated drive command, calibrate the brightness reading of each micro photosensitive unit to obtain the calibrated brightness reading of the micro photosensitive unit.

[0117] Step S44: Based on the calibrated brightness readings of the miniature photosensitive units and the brightness requirements of the currently displayed image content in the local area, calculate the brightness error of each local area.

[0118] Step S45: Based on the brightness error of each local area, perform differentiated fine-tuning on the light-emitting devices corresponding to the local area.

[0119] Specifically, miniature photosensitive units are deployed within each backlight zone to provide more detailed brightness feedback than traditional zone sensing. Each miniature photosensitive unit is configured to monitor the brightness output of its corresponding local area. Real-time acquisition of brightness readings from each miniature photosensitive unit means that these readings can be acquired at a sufficiently high frequency to reflect dynamic changes in backlight brightness in a timely manner.

[0120] The process of calibrating the brightness reading of each micro photosensitive unit aims to eliminate the inherent error or drift of the micro photosensitive unit itself, and to align its reading with the macro brightness data of the entire backlight zone (i.e., the corrected brightness reading) and the expected output of the light-emitting device (i.e., the compensated drive command), so as to ensure the accuracy and consistency of the local brightness reading.

[0121] In practical applications, brightness requirement refers to the desired brightness level in a specific local area based on the currently displayed image content. By comparing the calibrated brightness readings of the miniature photosensitive unit with this brightness requirement, the brightness deviation of each local area can be precisely quantified. Differential fine-tuning of the light-emitting devices corresponding to each local area based on the brightness error means independently and precisely adjusting the driving current or pulse width modulation (PWM) signal of the light-emitting devices (e.g., individual LEDs or small clusters of LEDs in an LED array) within each local area according to the calculated local brightness error, in order to eliminate local brightness non-uniformity.

[0122] This application's solution achieves hyperlocalized perception of backlight brightness by deploying multiple micro-photosensitive units within each backlight zone. These micro-photosensitive units collect brightness readings of their corresponding local areas in real time, and combine this data with the overall corrected brightness readings of the backlight zone and the compensated drive commands of the light-emitting devices for calibration, thereby obtaining highly accurate local brightness information. Subsequently, these calibrated micro-photosensitive unit brightness readings are compared with the brightness requirements of the currently displayed image content in the corresponding local areas, accurately calculating the brightness error of each local area. Based on these fine-grained local brightness errors, the system can perform differentiated fine-tuning of the light-emitting devices corresponding to local areas, rather than simply making overall adjustments at the zone level. This mechanism enables the backlight control system to identify and correct subtle brightness differences that are difficult to detect with traditional zone control, thereby effectively solving the problem of uneven local brightness caused by minute manufacturing tolerances, local hot spots, or uneven aging of light-emitting devices or photosensitive devices.

[0123] This application also discloses a backlight uniformity control system for an LCD liquid crystal display screen. Please refer to [link to specific embodiments]. Figure 13 The system 100 includes: The acquisition module 101 is used to acquire the first adjustment parameters of the photosensitive device and the second adjustment parameters of the light-emitting device inside the display screen.

[0124] The photosensitive device calibration module 102 is used to calibrate the original brightness reading of the photosensitive device based on the first adjustment parameters of the photosensitive device and a pre-established performance prediction model of the photosensitive device, so as to obtain the calibrated brightness reading.

[0125] The light-emitting device compensation module 103 is used to compensate the original driving command of the light-emitting device based on the second adjustment parameter of the light-emitting device and the pre-established performance prediction model of the light-emitting device, so as to obtain the compensated driving command.

[0126] The drive adjustment module 104 is used to adjust the drive of the light-emitting device based on the corrected brightness reading and the compensated drive command, so as to maintain the backlight uniformity of the display screen.

[0127] The system collects key adjustment parameters through an acquisition module, precisely corrects sensor readings through a photosensitive device correction module, pre-adjusts drive commands through a light-emitting device compensation module, and finally uses a drive adjustment module to finely drive the light-emitting device by combining the corrected brightness readings and the compensated drive commands, so as to ensure that the display can maintain excellent backlight uniformity during long-term operation.

[0128] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A method for controlling the backlight uniformity of an LCD liquid crystal display screen, characterized in that, Includes the following steps: Obtain the first adjustment parameters of the photosensitive device and the second adjustment parameters of the light-emitting device inside the display screen; Based on the first adjustment parameter of the photosensitive device and the pre-established performance prediction model of the photosensitive device, the original brightness reading of the photosensitive device is corrected to obtain the corrected brightness reading. Based on the second adjustment parameter of the light-emitting device and the pre-established performance prediction model of the light-emitting device, the original driving command of the light-emitting device is compensated to obtain the compensated driving command. Based on the corrected brightness reading and the compensated driving command, the driving of the light-emitting device is adjusted to maintain the backlight uniformity of the display screen. The step of obtaining the first adjustment parameter of the photosensitive device inside the display screen includes: Obtain the cumulative workload information of the photosensitive device and / or the response deviation ratio of the photosensitive device to each color of light; The step of correcting the original brightness reading of the photosensitive device based on the first adjustment parameter of the photosensitive device and the pre-established performance prediction model of the photosensitive device to obtain the corrected brightness reading includes: The performance prediction model of the photosensitive device is modified according to the cumulative workload information and / or the response deviation ratio of the photosensitive device to each color of light. The original luminance readings were corrected by using a modified photosensitive device performance prediction model to obtain corrected luminance readings.

2. The method for controlling the backlight uniformity of an LCD liquid crystal display screen according to claim 1, characterized in that, The steps for obtaining the cumulative workload information of the photosensitive device include: The duration of operation of the photosensitive device in high dynamic range mode and the duration of cumulative high temperature in the region where the photosensitive device is located are obtained. The cumulative workload information of the photosensitive device is obtained based on the duration of operation in the high dynamic range mode and the duration of the cumulative high temperature in the area where the photosensitive device is located.

3. The method for controlling the backlight uniformity of an LCD liquid crystal display screen according to claim 1, characterized in that, The steps for parameter correction of the photosensitive device performance prediction model based on cumulative workload information include: The expected decrease rate of the photosensitive device's response to light intensity is obtained based on the cumulative workload information of the photosensitive device. The parameters of the photosensitive device performance prediction model are adjusted based on the expected decrease in responsivity.

4. The method for controlling the backlight uniformity of an LCD liquid crystal display screen according to claim 1, characterized in that, The step of obtaining the response deviation ratio of the photosensitive device to each color of light includes: When the display screen is not in operation, control the display screen to sequentially display test patterns of different colors; Collect the brightness readings of the photosensitive device when displaying each test pattern; The brightness readings of the acquired photosensitive device are compared with the initial calibration data of each test pattern to calculate the response deviation ratio of the photosensitive device to each color of light. The step of correcting the parameters of the photosensitive device performance prediction model based on the response deviation ratio of the photosensitive device to each color of light includes: Based on the calculated spectral response deviation ratio, the performance prediction model of the photosensitive device is corrected, and the prediction parameters for sensitivity deviations of different colors of light are updated. The step of correcting the original luminance reading using the modified photosensitive device performance prediction model to obtain the corrected luminance reading includes: During the daily operation of the photosensitive device, the main spectral components of each backlight zone in the current displayed image frame are analyzed in real time. By combining the corrected photosensitive device performance prediction model with the spectral composition of the currently displayed image, a spectral deviation compensation factor is calculated. The original brightness reading of the photosensitive device is multiplied by the spectral deviation compensation factor to obtain the corrected brightness reading.

5. The method for controlling the backlight uniformity of an LCD liquid crystal display screen according to claim 1, characterized in that, The step of obtaining the second adjustment parameter of the light-emitting device inside the display screen includes: Obtain the cumulative workload information of the light-emitting devices inside the display screen and / or the actual attenuation ratio of the light-emitting device array for each color of light; The step of compensating the original driving command of the light-emitting device based on the second adjustment parameter of the light-emitting device and the pre-established performance prediction model of the light-emitting device to obtain the compensated driving command includes: The performance prediction model for the light-emitting device is modified based on the cumulative workload information of the light-emitting device and / or the actual attenuation ratio of each color of light by the light-emitting device array; The original driving command is compensated by the modified light-emitting device performance prediction model to obtain the compensated driving command.

6. The method for controlling the backlight uniformity of an LCD liquid crystal display screen according to claim 5, characterized in that, The step of obtaining the cumulative workload information of the light-emitting devices inside the display screen includes: The duration of operation of the light-emitting device inside the display screen in high dynamic range mode, the duration of cumulative high temperature in the area where the light-emitting device is located, and the duration of high current of the light-emitting device are obtained. The cumulative workload information of the light-emitting device is obtained based on the duration of operation of the light-emitting device in high dynamic range mode, the cumulative high temperature duration of the region, and the high current duration. The step of correcting the parameters of the light-emitting device performance prediction model based on the cumulative workload information of the light-emitting device includes: The expected brightness decay ratio is obtained based on the cumulative workload information of the light-emitting device; The parameters of the light-emitting device performance prediction model are corrected based on the expected brightness attenuation ratio.

7. The method for controlling the backlight uniformity of an LCD liquid crystal display screen according to claim 5, characterized in that, The step of obtaining the actual attenuation ratio of each color of light for the light-emitting device array inside the display screen includes: When the display is not in operation, the array of light-emitting devices in each backlight zone is activated, so that it displays the light corresponding to each color in sequence. Collect brightness readings of the photosensitive device when displaying each color; Record the current concentration and temperature of volatile organic compounds inside the backlight module; The collected brightness readings are compared with the initial calibration data of the light-emitting device array to calculate the actual attenuation ratio of the light-emitting device array for each color of light. The step of correcting the parameters of the light-emitting device performance prediction model based on the actual attenuation ratio of each color of light by the light-emitting device array includes: Based on the calculated actual attenuation ratio of each color of light by the light-emitting device array and the recorded concentration and temperature of volatile organic compounds, the parameters of the light-emitting device performance prediction model are corrected, and the independent attenuation prediction functions for red, green and blue light are updated. The step of compensating the original driving command using the modified light-emitting device performance prediction model to obtain the compensated driving command includes: When the backlight control system calculates the target brightness of each light-emitting device array, it queries the updated light-emitting device performance prediction model to obtain the expected attenuation ratio of the light-emitting device array for red, green and blue light. Generate a spectral compensation matrix, which contains compensation factors for each color of light; Multiply the originally calculated driving current by the corresponding spectral compensation factor to obtain the compensated driving current; The command for the compensated drive current is sent to the driver chip of the light-emitting device.

8. The method for controlling the backlight uniformity of an LCD liquid crystal display screen according to claim 1, characterized in that, The step of adjusting the driving of the light-emitting device based on the corrected brightness reading and the compensated driving command to maintain the backlight uniformity of the display screen includes: In each backlight zone of the display screen, a plurality of micro photosensitive units are deployed, and each micro photosensitive unit corresponds to a local area within the backlight zone; The brightness readings of each of the micro photosensitive units are collected in real time; Based on the corrected brightness reading of the backlight zone where the micro photosensitive unit is located and the compensated driving command, the brightness reading of each micro photosensitive unit is calibrated to obtain the calibrated brightness reading of the micro photosensitive unit. Based on the calibrated brightness readings of the micro-photosensitive units and the brightness requirements of the currently displayed image content in the local area, the brightness error of each local area is calculated. Based on the brightness error of each local region, the light-emitting devices corresponding to the local regions are finely adjusted.

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