OLED display panel and control method thereof

Abstract

The application provides an OLED display panel and a control method thereof, and relates to the technical field of flat panel display with components specially suitable for light emission, such as organic light emitting diode, the application forms temperature-decay closed-loop compensation: temperature data and light emission efficiency decay amount are obtained through sensing detection, a temperature-decay kinetic model predicts future decay trend, driving adjustment dynamically changes parameters according to the prediction result, and the adjusted effect is verified in the next round of sensing detection, so that closed-loop control of continuous optimization is realized; the temperature-decay closed-loop compensation control method systematically associates light emission efficiency decay sensing and temperature sensing in time and space, realizes the change from passive compensation to active prediction through the establishment of the temperature-decay kinetic model, can take protective measures of reducing driving current in advance before temperature causes decay acceleration, and effectively prolongs the service life of the OLED display panel.

Description

Technical Field

[0001] This invention relates to the field of flat panel display technology with components specifically designed for light emission, such as those using organic light-emitting diodes, and more specifically to an OLED display panel and its control method. Background Technology

[0002] Organic electroluminescent diodes (OLEDs) are considered to be the next generation of emerging application technologies for flat panel displays due to their superior characteristics, such as self-illumination, no need for backlight, high contrast, thinness, wide viewing angle, fast response speed, applicability to flexible panels, wide operating temperature range, and simpler construction and manufacturing process.

[0003] A typical OLED display panel includes a TFT backplane, an OLED display layer, and necessary driving circuitry. The TFT backplane integrates an array of driving transistors to provide driving current to the OLED pixel cells to control their brightness. Over time, the OLED pixel cells experience a decline in luminous efficiency (i.e., aging), and the threshold voltage of the driving transistors also drifts, leading to decreased display brightness and reduced uniformity.

[0004] Therefore, an OLED display panel and its control method are provided. Summary of the Invention

[0005] To address the problems mentioned in the background art, the present invention provides the following technical solution: an OLED display panel, comprising: The OLED display layer includes multiple OLED pixel units arranged in an array; TFT backplane, including an array of driving transistors for driving OLED pixel units; The sensing layer is located between the TFT backplane and the OLED display layer. The sensing layer integrates multiple arrayed light sensors and multiple thermal sensing elements. The light sensors are located at the projection position of the gap area of ​​the OLED pixel unit to receive light signals from the OLED pixel unit and collect their own dark current. The thermal sensing elements are dispersed in different areas of the OLED display panel and are fewer in number than the light sensors to collect local temperature values. The OLED display panels are configured to perform operations alternately over time. In the first sensing mode, during non-display periods, at least one OLED pixel unit is controlled to emit a test light pulse, which is received by the corresponding light sensor and the light signal intensity value is output to determine the luminous efficiency attenuation of the OLED pixel unit and update the luminous efficiency compensation parameters. In the second sensing mode, during the dark state detection period, all OLED pixel units stop emitting light. The thermal sensing element collects the local temperature value of its respective area, while the light sensor collects the dark current value of each area. The OLED display panel uses a pre-stored dark current-temperature calibration curve to convert the dark current value into a calibration temperature value and cross-verifies it with the local temperature value at the corresponding location. This corrects the local temperature value collected by the sparsely distributed thermal sensing element, obtains highly reliable temperature data, and then constructs a pixel-level thermal distribution map.

[0006] Furthermore, the test light pulse is a subthreshold test light pulse. The driving transistor is configured to be in a subthreshold conduction state during non-display periods, and the corresponding OLED pixel unit is driven to emit a subthreshold test light pulse with a subthreshold current. The sensing layer compares the collected subthreshold test light pulse intensity value with a preset reference value to determine the threshold voltage drift of the driving transistor and update the threshold voltage compensation parameters.

[0007] Furthermore, the thermal sensing elements include at least five disposed in the four corner areas and the center area of ​​the OLED display panel, and are polycrystalline silicon thermistors or metal thin film thermistors.

[0008] Furthermore, the dark current-temperature calibration curve is configured for adaptive updating: when the deviation between the calibration temperature value and the local temperature value in the same area is within a preset consistency threshold in N consecutive second sensing modes, the dark current-temperature calibration curve is incrementally corrected based on the pairing data of dark current and local temperature values ​​in those N times.

[0009] Furthermore, the OLED display panel also identifies abnormally high-temperature areas where the temperature gradient exceeds a preset gradient threshold based on the temperature gradient of each region in the pixel-level thermal distribution map. When the temperature distribution pattern of the abnormally high-temperature area does not conform to the normal heat dissipation law, an abnormal alarm signal is output.

[0010] Furthermore, this includes the following steps executed in a loop: S1: During non-display periods, execute the first sensing mode to obtain the luminous efficiency decay of the OLED pixel unit in the target area, and update the luminous efficiency compensation parameter according to the graded strategy. The graded strategy is: when the luminous efficiency decay is in the mild range, increase the luminous efficiency compensation parameter; when it is in the severe range, increase the luminous efficiency compensation parameter and decrease the maximum allowable grayscale value. S2: During the dark state detection period, the second sensing mode is executed to obtain the local temperature value after cross-validation correction, and a pixel-level thermal distribution map is constructed through a spatial interpolation algorithm; S3: Perform spatial correlation analysis between the pixel-level thermal distribution map and the luminous efficiency decay of each region obtained through S1 to determine the influence weight of temperature on decay; based on the influence weight and historical decay rate data, establish a temperature-decay dynamics model for each region to predict the future decay rate; when it is predicted that the decay of a certain region will be accelerated due to the increase in temperature, dynamically reduce the driving current of the OLED pixel unit in that region, and correct the compensation parameters according to the pixel-level thermal distribution map, thereby realizing temperature-decay closed-loop compensation.

[0011] Furthermore, S1 also includes cross-channel degradation correlation detection: simultaneously driving the blue, red, and green OLED sub-pixel units at the same pixel position to emit test light pulses, and obtaining the luminous efficiency attenuation of each color sub-pixel respectively; when the luminous efficiency attenuation of the blue sub-pixel exceeds the blue warning threshold, based on the pre-calibrated red-blue attenuation correlation coefficient and green-blue attenuation correlation coefficient, predicting the future attenuation rate of the red and green sub-pixels at the same pixel position, and adjusting their compensation parameters in advance.

[0012] Furthermore, it also includes adaptive sensing frequency: maintaining the cumulative luminous dose count value for each area of ​​the OLED display panel, and shortening the sensing cycle interval of S1 and S2 for that area when the cumulative luminous dose count value of any area reaches the preset dose threshold.

[0013] Furthermore, S2 also includes a confidence assessment of the thermal distribution map: after constructing a pixel-level thermal distribution map, the interpolation residual at the location of each thermal sensing element is calculated using the dark current value of the light sensor. When the interpolation residual exceeds a preset threshold, the area is marked as a low-confidence area, and supplementary temperature acquisition is performed on the area in the subsequent dark state detection period.

[0014] Furthermore, it also includes screen burn-in protection for static control areas: the cumulative luminous dose count of each OLED pixel unit in the static control area is counted, and when it exceeds the preset cumulative luminous dose count threshold, a micro-displacement is triggered, which shifts the display position by one or more sub-pixel distances along a preset direction, and passes the compensation parameters of the position before the shift to the OLED pixel unit that newly carries the display content at the position after the shift; the displacement period of the micro-displacement is inversely proportional to the growth rate of the cumulative luminous dose count.

[0015] Beneficial effects The present invention has the following beneficial effects: (1) This invention integrates a sensing layer between the TFT backplane and the OLED display layer, simultaneously realizing both optical sensing and temperature sensing functions using the same sensing layer: the light sensor 31 detects the luminous efficiency of the OLED pixel unit in the first sensing mode, and provides temperature verification data using dark current in the second sensing mode; the thermistor provides direct temperature measurement in the second sensing mode. The two types of sensing data complement and cross-verify each other in time and space, enabling the OLED display panel to simultaneously acquire pixel-level luminous efficiency decay information and highly reliable pixel-level thermal distribution maps without adding additional sensing modules, providing a data foundation for subsequent compensation driving and lifetime prediction.

[0016] (2) The subthreshold test light pulse generated by the subthreshold conduction method of the present invention has the following beneficial effects: the current in the subthreshold region is much more sensitive to the change of threshold voltage than that in the saturation region or the linear region, which enables the sensing detection to capture smaller threshold voltage drift and improves the sensing accuracy; the brightness of the subthreshold test light pulse is lower than the human eye perception threshold, and will not cause visual discomfort to the user when performing sensing detection during non-display periods; the power consumption of the driving transistor in the subthreshold conduction state is extremely low, and the impact of the sensing detection process on the energy consumption of the OLED display panel can be ignored.

[0017] (3) The adaptive update mechanism of the dark current-temperature calibration curve of the present invention has the following beneficial effects: the continuous consistency judgment ensures that the dark current-temperature calibration curve is only triggered when the measurement data of the thermal sensing element and the photosensitive element are reliable, thus avoiding the dark current-temperature calibration curve being incorrectly corrected due to individual abnormal measurement values; the incremental correction method does not require a complete recalibration process, and can continuously optimize the accuracy of the dark current-temperature calibration curve during the use of the OLED display panel, and compensate for the drift of dark current characteristics caused by long-term use of the photosensitive element; by assigning higher weights to new data through the weighted least squares method, the dark current-temperature calibration curve can adapt to the slow change trend of the dark current characteristics of the photosensitive element.

[0018] (4) The present invention forms a temperature-attenuation closed-loop compensation: the sensor detects and obtains the luminous efficiency attenuation amount and temperature data, the temperature-attenuation dynamic model predicts the future attenuation trend, the drive adjusts and dynamically changes the parameters according to the prediction results, and the effect of the adjustment is verified in the next round of sensor detection, realizing continuous optimization of closed-loop control; the temperature-attenuation closed-loop compensation control method systematically correlates the luminous efficiency attenuation sensing and temperature sensing in time and space, and realizes the transformation from passive compensation to active prediction by establishing a temperature-attenuation dynamic model, which can take protective measures to reduce the driving current in advance before the temperature causes accelerated attenuation, effectively extending the service life of the OLED display panel.

[0019] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0020] Figure 1 This is a cross-sectional view of the entire invention.

[0021] Figure 2 This is a schematic diagram of the sensing layer of the present invention.

[0022] Figure 3 This is a flowchart of the entire invention.

[0023] Figure 4 This is a partial flowchart of the first sensing mode of the present invention.

[0024] Figure 5 This is a flowchart illustrating the adaptive sensing frequency of the present invention.

[0025] Figure 6 This is a partial flowchart of the second sensing mode of the present invention.

[0026] Figure 7 This is a partial flowchart of the static control area burn-in protection method of the present invention.

[0027] In the diagram: OLED display layer 1, TFT backplane 2, sensing layer 3, light sensor 31, and thermal sensing element 32. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Please see Figures 1 to 2 This invention provides a technical solution: an OLED display panel, comprising: From bottom to top, it includes a TFT backplane 2, a sensing layer 3, and an OLED display layer 1; OLED display layer 1 includes multiple OLED pixel units arranged in an array; TFT backplane 2 includes a driving transistor array for driving OLED pixel units; The TFT backplane 2 is disposed at the bottom layer of the OLED display panel, and a driving transistor array is disposed thereon. Each driving transistor in the driving transistor array is electrically connected to an OLED pixel unit in the OLED display layer 1, and is used to provide driving current to the OLED pixel unit to control its light emission brightness. The source of the driving transistor receives data voltage through a data line, the gate receives scan signal through a scan line, and the drain is connected to the anode of the corresponding OLED pixel unit through a connecting electrode.

[0030] The TFT backplane 2 also includes a gate driving circuit and a data driving circuit. The gate driving circuit outputs a scan signal line by line to select the gate of the driving transistor. The data driving circuit outputs a data voltage to the corresponding data line during the scan signal selection period, thereby writing the display data into the gate-source voltage of the driving transistor. The sensing layer 3 is disposed between the TFT backplane 2 and the OLED display layer 1. The sensing layer 3 integrates multiple arrayed light sensors 31 and multiple thermal sensing elements 32. The light sensors 31 are disposed at the projection position of the gap area of ​​the OLED pixel unit, and are used to receive light signals from the OLED pixel unit and collect their own dark current. The thermal sensing elements 32 are dispersed in different areas of the OLED display panel and are fewer in number than the light sensors 31, and are used to collect local temperature values. The sensing layer 3 is disposed between the TFT backplane 2 and the OLED display layer 1.

[0031] The panel controller (not shown in the figure, integrated in the peripheral driving circuit of the TFT backplane 2 or as a separate chip) is electrically connected to the gate driving circuit, the data driving circuit, the light sensor 31 and the thermal sensing element 32, and is used to perform sensing detection, compensation calculation and alarm output.

[0032] Multiple arrayed optical sensors 31 and multiple thermal sensing elements 32 are integrated on the sensing layer 3.

[0033] The number of light sensors 31 corresponds to the number of OLED pixel units. Each light sensor 31 is located at the projection position of the gap area between one or more OLED pixel units, that is, the light sensor 31 is located directly below the pixel gap area between OLED pixel units, so that the light sensor 31 can receive light signals scattered from the corresponding OLED pixel unit from top to bottom or side, without blocking the front light emission path of the OLED pixel unit.

[0034] The thermal sensing elements 32 are distributed in different areas of the OLED display panel, and their number is less than that of the light sensors 31. The thermal sensing elements 32 are used to collect the local temperature value of their respective areas. The OLED display panel is configured to alternate between a first sensing mode and a second sensing mode over time. The OLED display panel is configured to alternate between the first sensing mode and the second sensing mode in time. In the first sensing mode, during non-display periods, at least one OLED pixel unit is controlled to emit a test light pulse, which is received by the corresponding light sensor 31 and the light signal intensity value is output to determine the luminous efficiency attenuation of the OLED pixel unit and update the luminous efficiency compensation parameters. During non-display periods (i.e., during vertical blanking), at least one target OLED pixel unit is controlled to emit test light pulses.

[0035] The data driving circuit outputs a test voltage to the corresponding driving transistor, which turns on the driving transistor and provides a test current to the OLED pixel unit. The OLED pixel unit emits a test light pulse under the drive of the test current.

[0036] The light sensor 31, located at the projection position of the gap area between the OLED pixel units, receives the test light pulse, converts the received light signal into an electrical signal, and outputs the light signal intensity value.

[0037] The signal processing circuit in sensing layer 3 compares the light signal intensity value with the pre-stored initial luminous intensity value (i.e., the luminous intensity value recorded when the OLED pixel unit leaves the factory or during the last calibration). The difference between the two reflects the luminous efficiency decay of the OLED pixel unit.

[0038] Based on the amount of luminous efficiency decay, the corresponding luminous efficiency compensation parameter is updated. This luminous efficiency compensation parameter is stored in the compensation memory of the panel controller and is used to correct the data voltage in subsequent normal display driving to compensate for the decay of luminous efficiency. In the second sensing mode, during the dark state detection period, all OLED pixel units stop emitting light. The thermal sensing element 32 collects the local temperature value of its respective area, while the light sensor 31 collects the dark current value of each area. The OLED display panel uses a pre-stored dark current-temperature calibration curve (e.g., dark current 12.5pA at 20℃, dark current 18.2pA at 25℃, etc.) to convert the dark current value into a calibration temperature value and cross-calibrate it with the local temperature value at the corresponding location. This corrects the local temperature value collected by the sparsely distributed thermal sensing element 32, obtains highly reliable temperature data, and then constructs a pixel-level thermal distribution map. During the dark state detection period (i.e., when the panel is in a low brightness display state or a specific calibration pause period), all OLED pixel units stop emitting light, that is, the data driving circuit outputs zero data voltage, which turns off all driving transistors and no current flows through the OLED pixel units; Under these conditions, the light sensors 31 collect their respective dark current values ​​in the absence of external light. The magnitude of the dark current value has a specific functional relationship with the local temperature at the location of the light sensor 31. Simultaneously, the thermal sensing elements 32 collect the local temperature values ​​of their respective areas. After reading the dark current values ​​of all light sensors 31 and the local temperature values ​​of all thermal sensing elements 32, the panel controller uses a pre-stored dark current-temperature calibration curve to convert the dark current values ​​at the location of each light sensor 31 into calibration temperature values.

[0039] Subsequently, each verified temperature value is cross-verified with the local temperature value collected by the thermal sensing element 32 whose spatial location is closest to it: If the deviation between the two is within the preset consistency threshold range, the temperature data for that area is considered reliable. If the deviation exceeds the consistency threshold, the measured value of the thermal sensing element 32 is corrected (for example, by using the weighted average of the calibration temperature value and the local temperature value as the corrected temperature value), or the measured value of the thermal sensing element 32 is marked as needing to be reviewed.

[0040] Through the above cross-validation process, the dark current information of the densely distributed light sensors 31 is used to correct the measurement values ​​of the sparsely distributed thermal sensing elements 32, thereby obtaining highly reliable temperature data. Then, the panel controller constructs a pixel-level thermal distribution map of the entire OLED display panel based on all the corrected temperature data.

[0041] In practical implementation, the sensing layer 3 is integrated between the TFT backplane 2 and the OLED display layer 1, simultaneously realizing both optical sensing and temperature sensing functions: the light sensor 31 detects the luminous efficiency of the OLED pixel unit in the first sensing mode, and provides temperature verification data using dark current in the second sensing mode; the thermistor 32 provides direct temperature measurement in the second sensing mode. The two types of sensing data complement and cross-verify each other in time and space, enabling the OLED display panel to simultaneously acquire pixel-level luminous efficiency decay information and highly reliable pixel-level thermal distribution maps without adding additional sensing modules, providing a data foundation for subsequent compensation driving and lifetime prediction.

[0042] Furthermore, the test light pulse is a subthreshold test light pulse. The driving transistor is configured to be in a subthreshold conduction state during non-display periods, and the corresponding OLED pixel unit is driven to emit a subthreshold test light pulse with a subthreshold current. The sensing layer 3 compares the collected subthreshold test light pulse intensity value with a preset reference value, determines the threshold voltage drift of the driving transistor, and updates the threshold voltage compensation parameters.

[0043] In practice, the brightness of the subthreshold test light pulse is much lower than the brightness level during normal display, so as to ensure that the flicker is not perceived by the human eye when performing sensor detection during non-display periods.

[0044] During non-display periods, the driving transistor is configured in a subthreshold on-state. During the first sensing mode, the data driving circuit outputs a specific test gate voltage to the gate of the target driving transistor. This test gate voltage is slightly lower than the threshold voltage of the driving transistor, causing it to operate in the subthreshold region (weak inversion region). In this state, the drain current of the driving transistor is in the nanoampere to picoampere range, and this subthreshold current drives the corresponding OLED pixel unit to emit a subthreshold test light pulse.

[0045] When the first sensing mode is activated, the data driving circuit outputs a test gate voltage to the target driving transistor, causing it to enter the subthreshold conduction state. The subthreshold current output by the driving transistor flows through the OLED pixel unit, causing it to emit a subthreshold test light pulse. Since the luminous intensity of the OLED pixel unit is positively correlated with the driving current, and the current in the subthreshold region is extremely sensitive to changes in the gate-source voltage, the intensity of the subthreshold test light pulse can sensitively reflect minute changes in the threshold voltage of the driving transistor.

[0046] A light sensor 31, located at the projection position of the gap region between the OLED pixel units, receives the subthreshold test light pulse, converts it into an electrical signal, and outputs a light signal intensity value. The signal processing circuit in the sensing layer 3 compares this light signal intensity value with a preset reference value. The preset reference value is the standard light signal intensity value that should be obtained after the light signal emitted by the OLED pixel unit is converted by the light sensor 31 when the test gate voltage is at the nominal value, under the condition that the threshold voltage of the driving transistor is at its nominal value. The threshold voltage of the driving transistor will drift with the extension of usage time and temperature changes. Therefore, when the measured light signal intensity value deviates from the preset reference value, the amount of deviation corresponds to the threshold voltage drift of the driving transistor.

[0047] Based on the threshold voltage drift, sensing layer 3 updates the threshold voltage compensation parameter corresponding to the driving transistor according to a pre-calibrated drift-compensation parameter correspondence. This threshold voltage compensation parameter is stored in the compensation memory of the panel controller. During subsequent normal display driving, the data driving circuit corrects the output data voltage based on the updated threshold voltage compensation parameter to offset the impact of the threshold voltage drift on the driving current.

[0048] Generating subthreshold test light pulses using a subthreshold conduction method has the following advantages: the current in the subthreshold region is much more sensitive to changes in threshold voltage than in the saturation or linear region, enabling the sensor to capture smaller threshold voltage drifts and improving sensing accuracy; the brightness of the subthreshold test light pulse is lower than the human eye's perception threshold, so it will not cause visual discomfort to users when performing sensing during non-display periods; the power consumption of the driving transistor in the subthreshold conduction state is extremely low, and the impact of the sensing process on the energy consumption of the OLED display panel is negligible.

[0049] Furthermore, the thermal sensing element 32 includes at least five disposed in the four corner areas and the center area of ​​the OLED display panel, and is a polycrystalline silicon thermistor or a metal thin film thermistor.

[0050] In a specific implementation, the thermal sensing element 32 includes at least five thermal sensing elements 32 disposed in the four corner areas and the center area of ​​the OLED display panel. Specifically, the five thermal sensing elements 32 are respectively disposed in the upper left corner area, upper right corner area, lower left corner area, lower right corner area and geometric center area of ​​the OLED display panel.

[0051] Five thermal sensing elements 32 are arranged in a quincunx pattern on the sensing layer 3. The four corner thermal sensing elements 32 are located at an equivalent distance from the corresponding corner vertex (for example, at a distance of 10% to 15% of the short side length of the panel from each edge), and the central thermal sensing element 32 is located at the intersection of the two diagonals of the panel.

[0052] The thermal sensing element 32 is a polysilicon thermistor or a metal thin film thermistor.

[0053] When the thermistor 32 is a polysilicon thermistor: the polysilicon thermistor is formed by sequentially depositing a polysilicon thin film on the substrate of the sensing layer 3 and then forming a specific resistance pattern (e.g., a serpentine trace pattern to increase the effective resistance length) through photolithography and etching. The thickness of the polysilicon thin film is 50 nanometers to 200 nanometers, and the linewidth of the resistance pattern is 2 micrometers to 5 micrometers. The polysilicon thermistor utilizes the temperature coefficient of resistance (TCR) characteristic of polysilicon material, and its resistance value changes with temperature. During the manufacturing process, each polysilicon thermistor is calibrated, and its resistance value at different temperatures is recorded to establish a resistance-temperature correspondence table, which is stored in the panel controller.

[0054] In the second sensing mode, the panel controller obtains the current resistance value of the polysilicon thermistor by measuring the voltage across the polysilicon thermistor (under constant current driving conditions) or the current flowing through the polysilicon thermistor (under constant voltage driving conditions), and then looks up the corresponding local temperature value according to the resistance-temperature correspondence table.

[0055] When the thermistor 32 is a metal thin-film thermistor: the metal thin-film thermistor is formed by sputtering and depositing a metal thin film (e.g., platinum Pt thin film or nickel Ni thin film) on the substrate of the sensing layer 3, followed by photolithography and etching to form a resistance pattern. The thickness of the metal thin film is 20 nanometers to 100 nanometers, and the resistance pattern also uses serpentine traces to increase the effective resistance length. The metal thin-film thermistor utilizes the positive temperature coefficient characteristic of metal materials, and its resistance value increases linearly with increasing temperature. The calibration and measurement methods are similar to those of polycrystalline silicon thermistors, but since the resistance temperature coefficient of the metal thin film is approximately linear, its temperature can be directly derived from the linear formula without the need to consult tables.

[0056] Five thermistor elements 32 are connected to the temperature acquisition circuit in the panel controller via signal traces on the sensing layer 3. The temperature acquisition circuit includes a multiplexer and an analog-to-digital converter (ADC). In the second sensing mode, the multiplexer sequentially selects the five thermistor elements 32, and the ADC converts the analog temperature signal of each thermistor element 32 into a digital temperature value.

[0057] In this embodiment, the thermal sensing elements 32 are positioned at five locations: the four corners and the center of the OLED display panel. This allows for coverage of the panel's main hot and cold areas with a minimal number of elements. The center of the panel typically experiences the most concentrated heat generation (where the driver chip and main display content are located), while the four corners are sensitive areas for temperature gradient changes (adjacent to the heat dissipation structure of the frame). The local temperature values ​​collected by the five thermal sensing elements 32 serve as anchor data for temperature interpolation. Combined with the dark current verification data from the densely distributed light sensors 31, this allows for the construction of effective temperature distribution information covering the entire panel, achieving a balance between the number of sensing elements and the accuracy of temperature coverage.

[0058] Furthermore, the dark current-temperature calibration curve is configured for adaptive updating: when the deviation between the calibration temperature value and the local temperature value in the same area is within a preset consistency threshold in N consecutive second sensing modes, the dark current-temperature calibration curve is incrementally corrected based on the pairing data of dark current and local temperature values ​​in those N times.

[0059] In practical implementation, the dark current-temperature calibration curve is pre-stored in the non-volatile memory of the panel controller. This dark current-temperature calibration curve describes the correspondence between the dark current value of the photosensitive sensor 31 and the temperature of its location. The dark current-temperature calibration curve is established during factory calibration, recording the dark current values ​​of each photosensitive sensor 31 at multiple known temperature points (e.g., 20℃, 25℃, 30℃, 35℃, 40℃, 45℃, 50℃, 55℃, 60℃), and forming a continuous curve through polynomial fitting or piecewise linear interpolation.

[0060] The adaptive update process of the dark current-temperature calibration curve is as follows: The panel controller maintains a consistency counter for the region where each thermistor 32 is located, with an initial value of zero. Each time the second sensing mode is executed, the panel controller performs the following operations:

[0061] Step 1: Read the local temperature value collected by the thermal sensing element 32 .

[0062] Step 2: Read the dark current value of one or more photosensors 31 that are spatially closest to the thermal sensing element 32. .

[0063] Step 3: Based on the pre-stored dark current-temperature calibration curve, set the dark current value... Convert to calibration temperature value .

[0064] Step 4: Calculate the verification temperature value With local temperature value Deviation between .

[0065] Step 5: Determine the deviation Whether it is within the preset consistency threshold ε (e.g., ε=2℃).

[0066] If there is a deviation If the consistency threshold ε is within the range, the consistency counter for that region is incremented by 1. If there is a deviation If the consistency threshold ε is exceeded, the consistency counter for that region is reset to zero.

[0067] Step Six: When the consistency counter of a certain area accumulates to a preset number of times N (e.g., N=10), that is, in N consecutive second sensing modes, the calibration temperature value of that area is... With local temperature value deviation All are within the consistency threshold ε. The panel controller determines that the measured value of the thermal sensing element 32 in this area is highly consistent with the dark current data of the light sensor 31. At this time, it uses the dark current values ​​collected in these N second sensing modes. With local temperature value Paired data (N pairs of data in total) (k=1,2,…,N), incremental correction is performed on the dark current-temperature calibration curve.

[0068] The incremental correction method is as follows: add the new N sets of data pairs to the training dataset of the dark current-temperature calibration curve, and use the weighted least squares method to update the fitting parameters of the dark current-temperature calibration curve.

[0069] The weights of the new data pairs are set to... The weights of the original calibration data are set to ,and This allows the dark current-temperature calibration curve to prioritize tracking the latest changes in the dark current-temperature relationship (e.g., the dark current characteristic drift of the photosensitive sensor 31 due to aging). After the update is complete, the consistency counter is cleared and awaits the next round of accumulation.

[0070] Step 7: After the incremental correction is completed, the panel controller performs a consistency check on the updated dark current-temperature calibration curve. This involves using the updated dark current-temperature calibration curve to calculate the calculated temperature values ​​for all temperature points in the calibration dataset and calculating the root mean square error (RMSE). If the RMSE is lower than the preset curve quality threshold, the dark current-temperature calibration curve update is accepted; if the RMSE exceeds the curve quality threshold, the update is abandoned, the original dark current-temperature calibration curve is retained, and this event is recorded in the panel's log storage for subsequent maintenance and analysis.

[0071] In this embodiment, the adaptive update mechanism of the dark current-temperature calibration curve has the following beneficial effects: First, by ensuring continuous consistency judgment, the dark current-temperature calibration curve is only triggered when the measurement data of the thermal sensing element 32 and the light sensor 31 are both reliable, thus avoiding the dark current-temperature calibration curve being incorrectly corrected due to individual abnormal measurement values; Second, the incremental correction method does not require a complete recalibration process, and can continuously optimize the accuracy of the dark current-temperature calibration curve during the use of the OLED display panel, compensating for the drift of dark current characteristics of the light sensor 31 caused by long-term use; Third, by assigning higher weights to new data through the weighted least squares method, the dark current-temperature calibration curve can adapt to the slow changing trend of the dark current characteristics of the light sensor 31.

[0072] Furthermore, the OLED display panel also identifies abnormally high-temperature areas where the temperature gradient exceeds a preset gradient threshold based on the temperature gradient of each region in the pixel-level thermal distribution map. When the temperature distribution pattern of the abnormally high-temperature area does not conform to the normal heat dissipation law, an abnormal alarm signal is output.

[0073] In practical implementation, after completing the second sensing mode, the panel controller obtains temperature data that has been cross-validated and corrected. Combining the anchor point temperature data of the thermal sensing element 32 with the dark current verification data of the light sensor, a spatial interpolation algorithm is used to construct a pixel-level thermal distribution map of the OLED display panel, which is stored in the form of a two-dimensional temperature field.

[0074] The detection process for abnormally high temperature areas is as follows: Temperature gradient calculation: The panel controller performs gradient analysis on the temperature field data in the pixel-level thermal distribution map, calculates the temperature gradient components in the horizontal and vertical directions for each spatial location, and then obtains the magnitude of the temperature gradient at that location, reflecting the degree of temperature change per unit distance.

[0075] Gradient threshold determination: The magnitude of the temperature gradient at each location is compared with a preset gradient threshold. This threshold is predetermined based on the panel's normal operating temperature range and heat dissipation characteristics, representing the maximum allowable rate of temperature change under normal heat dissipation conditions. When the temperature gradient at a location exceeds this threshold, it is marked as a candidate abnormal region.

[0076] Verification of heat dissipation patterns: For each candidate abnormal region, taking the point with the highest temperature as the center, check whether the temperature value decreases monotonically point by point outward in multiple directions (such as horizontal, vertical, and two diagonal directions). Normal heat dissipation patterns require the temperature around the heat source to gradually decrease from the center outward, with isotherms exhibiting an approximately circular or elliptical distribution. If a non-monotonic change occurs in a certain direction where the temperature first decreases and then increases (i.e., a temperature "saddle point" exists), then the temperature distribution pattern in that region does not conform to normal heat dissipation patterns, and may be caused by factors such as blocked heat dissipation channels, localized short-circuit heating, or abnormalities in the thermal sensing element 32.

[0077] Abnormal Alarm Output: When a candidate abnormal region simultaneously meets the conditions of a temperature gradient exceeding a threshold and a heat dissipation pattern deviating from normal behavior, the panel controller determines it as an abnormally high-temperature region and outputs an abnormal alarm signal. The alarm signal includes: outputting a hardware alarm level signal via a general-purpose input / output interface (GPIO) to trigger external system protection actions; recording abnormal event information (timestamp, location coordinates, highest temperature value, temperature gradient magnitude) in the internal log memory; and optionally overlaying alarm prompts on the screen.

[0078] This embodiment employs both temperature gradient threshold judgment and heat dissipation pattern verification to identify abnormally high-temperature areas. This effectively distinguishes between normal high-temperature areas (such as normal temperature rise in the central display area caused by high-brightness content) and abnormal high-temperature areas (such as abnormal overheating caused by heat dissipation channel failure or local short circuit). An alarm is triggered only when the temperature gradient is abnormal and the temperature distribution pattern does not conform to normal heat dissipation patterns, thus avoiding false alarms caused by normal operating temperature rises and significantly improving the accuracy and reliability of anomaly detection.

[0079] refer to Figures 3 to 7 A method for controlling an OLED display panel includes the following steps, which are executed cyclically: S1: During non-display periods, execute the first sensing mode to obtain the luminous efficiency decay of the OLED pixel unit in the target area, and update the luminous efficiency compensation parameter according to the graded strategy. The graded strategy is: when the luminous efficiency decay is in the mild range, increase the luminous efficiency compensation parameter; when it is in the severe range, increase the luminous efficiency compensation parameter and decrease the maximum allowable grayscale value. In practice, during non-display periods (such as vertical blanking), the panel controller executes the first sensing mode. The OLED display panel is divided into several sensing target areas, and a representative OLED pixel unit is selected as the sensing target for each area. The driving transistor of the pixel is controlled to output a test current, emitting a test light pulse; the light sensor located between the pixels receives the test light pulse and outputs a light signal intensity value. The panel controller compares this value with a pre-stored initial luminous intensity value to calculate the luminous efficiency attenuation.

[0080] After obtaining the luminous efficiency attenuation, the panel controller updates the luminous efficiency compensation parameters according to a graded strategy: When the luminous efficiency decay is in the mild range (not exceeding the first threshold), increase the luminous efficiency compensation parameter; When the luminous efficiency decay is in the moderate range (exceeding the first threshold but not exceeding the second threshold), the luminous efficiency compensation parameter is further increased; When the luminous efficiency decay is in the severe range (exceeding the second threshold), while increasing the luminous efficiency compensation parameter, the maximum allowable grayscale value of the OLED pixel unit in that area is reduced to limit the maximum driving current.

[0081] The updated compensation parameters are stored in the compensation memory.

[0082] S2: During the dark state detection period, the second sensing mode is executed to obtain the local temperature value after cross-validation correction, and a pixel-level thermal distribution map is constructed through a spatial interpolation algorithm; In practical implementation, during the dark state detection period (when the panel is in a low brightness or calibration paused state), the panel controller executes the second sensing mode. First, all OLED pixel units are controlled to stop emitting light, and the dark current values ​​of all light sensors 31 and the local temperature values ​​of all thermal sensing elements 32 are collected. Using a pre-stored dark current-temperature calibration curve, the dark current values ​​of each light sensor are converted into calibration temperature values, and cross-calibrated with the local temperature values ​​of the nearest thermal sensing element 32 to obtain the corrected temperature values. Using the anchor point temperature data of the thermal sensing element 32 and the calibration temperature data of the light sensors as input, a pixel-level thermal distribution map is constructed using a spatial interpolation algorithm, recording the estimated temperature value at each pixel location.

[0083] S3: Perform spatial correlation analysis between the pixel-level thermal distribution map and the luminous efficiency decay of each region obtained through S1 to determine the influence weight of temperature on decay; based on the influence weight and historical decay rate data, establish a temperature-decay kinetic model for each region to predict the future decay rate; when it is predicted that the decay of a certain region will be accelerated due to the increase in temperature, dynamically reduce the driving current of the OLED pixel unit in that region, and correct the luminous efficiency compensation parameters according to the pixel-level thermal distribution map, thereby realizing temperature-decay closed-loop compensation.

[0084] In practical implementation, the panel controller performs spatial correlation analysis between the pixel-level thermal distribution map and the luminous efficiency decay in each region. For each sensing target area, the average temperature value and the luminous efficiency decay are paired to form a temperature-decay data pair. Using the data pairs accumulated over multiple sensing cycle intervals, regression or fitting methods are used to determine the influence weight of temperature on luminous efficiency decay, i.e., the contribution of each unit degree increase in temperature to the decay rate.

[0085] Based on the influence weights and historical decay rate data, the panel controller establishes a temperature-decay kinetic model for each region. This model states that the decay rate of luminous efficiency is determined by both the base decay rate constant and the temperature influence factor, where the temperature influence factor equals the influence weight multiplied by the offset of the current temperature relative to the reference temperature. The reference temperature can be set as either the reference temperature during normal panel operation or the initial calibration temperature, and the temperature offset is the difference between the current temperature and the reference temperature.

[0086] Using this model and combining it with the current pixel-level thermal distribution map, the panel controller predicts the decay rate of each area over a future period. When it is predicted that the decay rate of a certain area will significantly exceed a preset warning threshold due to an increase in temperature, two operations are performed:

[0087] Dynamically reduce the driving current of the OLED pixel unit in this area (e.g., reduce the data voltage or reduce the maximum allowable grayscale value) to slow down the accelerated degradation caused by temperature. The luminous efficiency compensation parameters for this region are corrected based on the pixel-level thermal distribution map: the product of the influence weight and the current temperature offset is used as a temperature correction factor and incorporated into the calculation of the luminous efficiency compensation parameters to ensure that the display brightness remains consistent while reducing the driving current.

[0088] The above S1, S2, and S3 are executed cyclically to form a temperature-attenuation closed-loop compensation: the sensor detects and obtains the luminous efficiency attenuation and temperature data, the temperature-attenuation kinetic model predicts the future attenuation trend, the driving adjustment dynamically changes the parameters based on the prediction results, and the effect of the adjustment is verified in the next round of sensor detection, realizing continuous optimization of closed-loop control.

[0089] The temperature-degradation closed-loop compensation control method systematically correlates luminous efficiency degradation sensing and temperature sensing in time and space. By establishing a temperature-degradation dynamic model, it realizes the transformation from passive compensation to active prediction. It can take protective measures to reduce driving current in advance before temperature causes accelerated degradation, effectively extending the service life of OLED display panels.

[0090] Furthermore, S1 also includes cross-channel degradation correlation detection: simultaneously driving the blue, red, and green OLED sub-pixel units at the same pixel position to emit test light pulses, and obtaining the luminous efficiency attenuation of each color sub-pixel respectively; when the luminous efficiency attenuation of the blue sub-pixel exceeds the blue warning threshold, based on the pre-calibrated red-blue attenuation correlation coefficient and green-blue attenuation correlation coefficient, predicting the future attenuation rate of the red and green sub-pixels at the same pixel position, and adjusting their luminous efficiency compensation parameters in advance.

[0091] In practical implementation, S1 also includes cross-channel degradation correlation detection. The OLED pixel unit consists of OLED sub-pixel units of three colors: blue, red, and green. Each pixel location contains blue, red, and green sub-pixels, emitting light of their respective colors. A light sensor 31 is positioned below each sub-pixel unit.

[0092] During the non-display period of the first sensing mode, the panel controller simultaneously drives the blue, red, and green OLED sub-pixel units at the same pixel location to emit test light pulses. The test light pulses for the three sub-pixels can be emitted sequentially within the same vertical blanking cycle, or they can be emitted alternately within three consecutive vertical blanking cycles. After each sub-pixel emits a test light pulse, the corresponding light sensor 31 receives the light signal and outputs an intensity value. The panel controller then calculates the luminous efficiency attenuation of the blue, red, and green sub-pixels respectively.

[0093] When the luminous efficiency decay of the blue sub-pixel exceeds the preset blue warning threshold, the panel controller determines that the blue sub-pixel has significantly decayed. Since the decay rate of blue OLED luminescent materials is usually faster than that of red and green materials, the early decay of blue sub-pixels often indicates that red and green sub-pixels at the same pixel location will experience accelerated decay in the future.

[0094] The panel controller uses pre-calibrated red-blue and green-blue attenuation correlation coefficients to predict the future attenuation rates of red and green sub-pixels at the same pixel location. These two correlation coefficients were pre-calibrated based on a large amount of aging test data and through statistical analysis of the attenuation correlation between different color sub-pixels. They respectively describe the predictive ability of the luminous efficiency attenuation of the blue sub-pixel on the future attenuation trends of the red and green sub-pixels. Specifically, the current luminous efficiency attenuation of the blue sub-pixel is multiplied by the red-blue and green-blue correlation coefficients, respectively, to obtain the predicted luminous efficiency attenuation of the red and green sub-pixels.

[0095] The panel controller adjusts the luminous efficiency compensation parameters in advance based on the predicted luminous efficiency decay of the red and green sub-pixels: on the basis of the current luminous efficiency compensation parameters of the red and green sub-pixels, the luminous efficiency compensation parameters are increased in proportion to the predicted luminous efficiency decay, so that the luminous efficiency compensation parameters are in place in advance before the actual decay reaches the current level, thereby achieving a smooth visual transition and avoiding color shift caused by sudden compensation.

[0096] Furthermore, it also includes adaptive sensing frequency: maintaining the cumulative luminous dose count value for each area of ​​the OLED display panel, and shortening the sensing cycle interval of S1 and S2 for that area when the cumulative luminous dose count value of any area reaches the preset dose threshold.

[0097] In practice, the panel controller maintains a cumulative luminous dose count for each area of ​​the OLED display panel. This count is updated as follows: the panel controller estimates the luminous dose of each OLED pixel during each frame based on the grayscale value of that pixel, combined with the relationship between driving current and data voltage (determined by driving current, emission time, and luminous efficiency coefficient), and adds this luminous dose to the cumulative luminous dose count of its respective area. The count values ​​for each area are stored in the panel controller's memory and updated after each normal display drive.

[0098] The panel controller presets a cumulative luminous dose count threshold for each region and maintains the current sensing cycle interval for each region (i.e., the interval between executing steps S1 and S2). The initial sensing cycle interval is set to a relatively large value (e.g., 30 minutes).

[0099] The adaptive sensing frequency process is as follows: The panel controller continuously monitors the cumulative luminous dose count value of each area. When the count value of any area reaches a preset threshold, the panel controller shortens the sensing cycle interval for performing S1 and S2 on that area. The shortening amount is dynamically adjusted according to the degree to which the count value exceeds the threshold: the more it exceeds the threshold, the shorter the sensing cycle interval, but it will not be lower than the preset minimum sensing cycle interval (e.g., 5 minutes).

[0100] When the panel controller performs step S1 and updates the luminous efficiency compensation parameters for a certain area, if the cumulative luminous dose count value of that area exceeds the threshold, the count value is subtracted by a preset reset offset (such as half of the threshold value) while updating the luminous efficiency compensation parameters. This allows the sensing cycle interval to be appropriately reduced after the compensation update, preventing the sensing frequency from remaining at the highest level for a long time and reducing interference from sensing detection on normal display.

[0101] Furthermore, S2 also includes a confidence assessment of the thermal distribution map: after constructing a pixel-level thermal distribution map, the interpolation residual at the location of each thermal sensing element 32 is calculated using the dark current value of the light sensor 31. When the interpolation residual exceeds a preset threshold, the area is marked as a low-confidence area, and supplementary temperature acquisition is performed on the area during the subsequent dark state detection period.

[0102] In practical implementation, S2 also includes a confidence assessment of the heat map. After constructing the pixel-level heat map, the panel controller performs a confidence assessment of the reliability of the heat map, as follows:

[0103] Interpolation residual calculation: The panel controller temporarily removes the actual measured temperature value (directly acquired by the thermal sensing element 32) at the location of each thermal sensing element 32 from the interpolation input dataset of the heat distribution map. Using only the temperature data from the remaining thermal sensing elements 32 and the dark current verification temperature data from all optical sensors 31, it recalculates the interpolated temperature value at that location using the same spatial interpolation algorithm as when constructing the heat distribution map. Then, the absolute deviation between the interpolated temperature value and the actual measured temperature value is calculated as the interpolation residual.

[0104] Interpolation residual threshold judgment: The interpolation residual at the location of each thermal sensing element 32 is compared with a preset interpolation residual threshold. If the interpolation residual is not greater than the threshold, the interpolation result in that area is considered reliable and marked as a high-confidence area; if the interpolation residual exceeds the threshold, the interpolation result is considered unreliable (possibly due to drastic changes in local temperature gradient, insufficient interpolation data, or large measurement deviation of the thermal sensing element 32), and marked as a low-confidence area.

[0105] Supplementary temperature acquisition for low-confidence areas: For low-confidence areas, the panel controller performs supplementary acquisition during subsequent dark-state detection periods. Specifically, during the next frame or multiple frames of dark-state detection, the number of photosensitive sensors 31 participating in dark current acquisition within that area is increased. For example, in the conventional second sensing mode, only one representative photosensitive sensor 31 is selected to acquire dark current values ​​for each sensing target area. However, during supplementary acquisition, all photosensitive sensors 31 within that area acquire dark current data to obtain denser dark current data. Then, the supplementarily acquired dark current values ​​are converted into calibration temperature values, which are cross-calibrated again with the local temperature values ​​of the thermal sensing element 32 to recalculate the temperature distribution of that area. Finally, the thermal distribution map of that local area is reconstructed using denser temperature data.

[0106] Confidence Update: After supplementary data acquisition, the panel controller recalculates the interpolation residuals and re-evaluates the threshold for that area. If the recalculated interpolation residuals fall below the threshold, the confidence level of that area is updated to a high-confidence area, and normal sensing frequency is restored. If the interpolation residuals still exceed the threshold, the low-confidence label is maintained, and the abnormal event is recorded in the log storage. Supplementary data acquisition continues for that area in the next sensing cycle interval. If the interpolation residuals fail to fall below the threshold after multiple consecutive supplementary acquisitions, the panel controller outputs a temperature data quality alarm signal for that area, indicating a possible systematic deviation in the external system, requiring manual inspection or maintenance.

[0107] Furthermore, it also includes burn-in protection for static control areas: the cumulative luminous dose count of each OLED pixel unit in the static control area is counted, and when it exceeds the preset cumulative luminous dose count threshold, a micro-displacement is triggered, which shifts the display position by one or more sub-pixel distances along a preset direction, and passes the compensation parameters (including luminous efficiency compensation parameters and threshold voltage compensation parameters) of the position before the shift to the OLED pixel unit that newly carries the display content at the position after the shift; the displacement period of the micro-displacement is inversely proportional to the growth rate of the cumulative luminous dose count.

[0108] In practice, certain areas of an OLED display panel display fixed content for extended periods (such as the channel logo area on a TV, the taskbar area on a monitor, and the status bar area on a smartphone), and these are called static control areas. The OLED pixel units in these areas emit light at a fixed grayscale value for a long time, resulting in a cumulative luminous dose count value far higher than that of dynamic display areas. This leads to a faster rate of luminous efficiency decay, and when switching to display other content, residual images may appear (i.e., burn-in).

[0109] The panel controller maintains a cumulative luminous dose count for each OLED pixel unit within the static control area. The update method is the same as the aforementioned cumulative luminous dose count, that is, the luminous dose is estimated and accumulated based on the data voltage value of each frame.

[0110] The burn-in protection process is as follows: Cumulative luminous dose count monitoring: The panel controller continuously monitors the cumulative luminous dose count of each OLED pixel unit within the static control area. When the count value of any pixel unit exceeds the preset cumulative luminous dose count threshold, a micro-displacement is triggered.

[0111] Micro-displacement: The panel controller controls the display driving circuit to shift the displayed content of the static control area by one or more sub-pixel distances along a preset direction. The preset direction can be horizontal, vertical, or diagonal, and the offset distance is usually one sub-pixel distance. Specifically, it modifies the display data mapping relationship of each pixel position within the static control area, so that the content originally displayed by a pixel unit at a certain position is now displayed by a pixel unit at an adjacent position. After the micro-displacement, the pixel unit at the original position displays surrounding content (such as background color or interpolated content from adjacent pixels), thus achieving a "rest" for that pixel unit.

[0112] Compensation Parameter Transfer: When a micro-displacement occurs, the panel controller transfers the compensation parameters (including luminous efficiency compensation parameters corresponding to the luminous efficiency attenuation and threshold voltage compensation parameters) from the previous position to the new OLED pixel unit carrying the displayed content at the new position. This allows the new pixel unit carrying the same displayed content to be driven according to the original compensation level, maintaining visual consistency of the displayed content. The transferred compensation parameters are used in this pixel unit until the next sensor detection updates its own compensation parameters.

[0113] Adaptive adjustment of the displacement period: The panel controller dynamically adjusts the displacement period of the micro-displacement based on the growth rate of the cumulative luminous dose count. The displacement period is inversely proportional to the growth rate of the cumulative luminous dose count: when the static control area displays high-brightness content, the growth rate is faster, the displacement period is shorter, and micro-displacements occur more frequently; when displaying low-brightness content, the growth rate is slower, the displacement period is longer, and micro-displacements occur less frequently. The displacement period has upper and lower limits to ensure that micro-displacements are performed within a reasonable frequency range.

[0114] Micro-displacement path planning: To avoid visual jitter, the panel controller presets a micro-displacement path (such as shifting horizontally from left to right, shifting by one sub-pixel distance each time, and turning back after reaching the boundary), so that the displayed content in the static control area moves continuously, smoothly, and slowly along the preset path. Because the sub-pixel distance offset is extremely small, the human eye cannot perceive the positional change at normal viewing distances.

Claims

1. An OLED display panel, characterized in that, include: The OLED display layer (1) includes multiple OLED pixel units arranged in an array; The TFT backplane (2) includes a driving transistor array for driving the OLED pixel units; A sensing layer (3) is disposed between the TFT backplate (2) and the OLED display layer (1). The sensing layer (3) integrates multiple array-arranged light sensors (31) and multiple thermal sensing elements (32). The light sensors (31) are disposed at the projection position of the gap area of ​​the OLED pixel unit, and are used to receive light signals from the OLED pixel unit and collect their own dark current. The thermal sensing elements (32) are dispersed in different areas of the OLED display panel and are fewer in number than the light sensors (31), and are used to collect local temperature values. The OLED display panel is configured to perform operations alternately over time: In the first sensing mode, during the non-display period, at least one of the OLED pixel units is controlled to emit test light pulses, which are received by the corresponding light sensor (31) and the light signal intensity value is output to determine the luminous efficiency attenuation of the OLED pixel unit and update the luminous efficiency compensation parameters. In the second sensing mode, during the dark state detection period, all OLED pixel units stop emitting light, and the local temperature value of their respective areas is collected by the thermal sensing element (32), while the dark current value of each area is collected by the light sensor (31). The OLED display panel uses the pre-stored dark current-temperature calibration curve to convert the dark current value into a calibration temperature value, and cross-calibrates it with the local temperature value at the corresponding position to correct the local temperature value collected by the sparsely distributed thermal sensing element (32), obtain highly reliable temperature data, and then construct a pixel-level thermal distribution map.

2. An OLED display panel according to claim 1, characterized in that, The test light pulse is a subthreshold test light pulse. The driving transistor is configured to be in a subthreshold conduction state during the non-display period, and drives the corresponding OLED pixel unit to emit the subthreshold test light pulse with a subthreshold current. The sensing layer (3) compares the collected subthreshold test light pulse intensity value with a preset reference value, determines the threshold voltage drift of the driving transistor, and updates the threshold voltage compensation parameters.

3. An OLED display panel according to claim 1, characterized in that, The thermal sensing element (32) includes at least five disposed in the four corner areas and the center area of ​​the OLED display panel, and is a polycrystalline silicon thermistor or a metal thin film thermistor.

4. The OLED display panel according to claim 1, characterized in that, The dark current-temperature calibration curve is configured for adaptive updating: when the deviation between the calibration temperature value and the local temperature value in the same area is within a preset consistency threshold in N consecutive second sensing modes, the dark current-temperature calibration curve is incrementally corrected based on the pairing data of dark current and local temperature values ​​in those N times.

5. An OLED display panel according to claim 1, characterized in that, The OLED display panel also identifies abnormally high-temperature areas where the temperature gradient exceeds a preset gradient threshold based on the temperature gradient of each region in the pixel-level thermal distribution map. When the temperature distribution pattern of the abnormally high-temperature area does not conform to the normal heat dissipation law, an abnormal alarm signal is output.

6. A method for controlling an OLED display panel, characterized in that, The following steps are included and executed in a loop: S1: During non-display periods, execute the first sensing mode to obtain the luminous efficiency decay of the OLED pixel unit in the target area, and update the luminous efficiency compensation parameter according to the grading strategy; the grading strategy is: when the luminous efficiency decay is in the mild range, increase the luminous efficiency compensation parameter; when it is in the severe range, decrease the maximum allowable grayscale value on the basis of increasing the luminous efficiency compensation parameter. S2: During the dark state detection period, the second sensing mode is executed to obtain the local temperature value after cross-validation correction, and a pixel-level thermal distribution map is constructed through a spatial interpolation algorithm; S3: Perform spatial correlation analysis between the pixel-level thermal distribution map and the luminous efficiency decay of each region obtained through S1 to determine the influence weight of temperature on decay; based on the influence weight and historical decay rate data, establish a temperature-decay dynamics model for each region to predict the future decay rate; when it is predicted that the decay of a certain region will be accelerated due to the increase in temperature, dynamically reduce the driving current of the OLED pixel unit in that region, and correct the compensation parameters according to the pixel-level thermal distribution map, thereby realizing temperature-decay closed-loop compensation.

7. The control method for an OLED display panel according to claim 6, characterized in that, S1 also includes cross-channel degradation correlation detection: simultaneously driving the blue, red, and green OLED sub-pixel units at the same pixel position to emit test light pulses, and obtaining the luminous efficiency attenuation of each color sub-pixel respectively; when the luminous efficiency attenuation of the blue sub-pixel exceeds the blue warning threshold, based on the pre-calibrated red-blue attenuation correlation coefficient and green-blue attenuation correlation coefficient, predicting the future attenuation rate of the red and green sub-pixels at the same pixel position, and adjusting their compensation parameters in advance.

8. The control method for an OLED display panel according to claim 6, characterized in that, It also includes adaptive sensing frequency: maintaining a cumulative luminous dose count value for each area of ​​the OLED display panel, and shortening the sensing cycle interval of S1 and S2 for that area when the cumulative luminous dose count value of any area reaches a preset dose threshold.

9. A control method for an OLED display panel according to claim 6, characterized in that, The S2 also includes a confidence assessment of the thermal distribution map: after constructing a pixel-level thermal distribution map, the interpolation residual at the location of each thermal sensing element (32) is calculated using the dark current value of the optical sensor (31). When the interpolation residual exceeds a preset threshold, the area is marked as a low-confidence area, and supplementary temperature acquisition is performed on the area during the subsequent dark state detection period.

10. A control method for an OLED display panel according to claim 6, characterized in that, It also includes screen burn-in protection for static control areas: the cumulative luminous dose count of each OLED pixel unit in the static control area is counted, and when it exceeds the preset cumulative luminous dose count threshold, a micro-displacement is triggered, which shifts the display position by one or more sub-pixel distances along a preset direction, and passes the compensation parameters of the position before the shift to the OLED pixel unit that newly carries the display content at the position after the shift; the displacement period of the micro-displacement is inversely proportional to the growth rate of the cumulative luminous dose count.

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